Effect of Silica on the Properties of Cellulose Acetatepolyethylene

download Effect of Silica on the Properties of Cellulose Acetatepolyethylene

of 15

Transcript of Effect of Silica on the Properties of Cellulose Acetatepolyethylene

  • 8/10/2019 Effect of Silica on the Properties of Cellulose Acetatepolyethylene

    1/15

    D e s a lin a tio n 3 55 (2 0 1 5) 110

    Contents listsavailable at S cien ceDirect

    Desalination

    journa l homepage: w wwels evi erco m! locate! "esa l

    #$$ect o$ silica on the properties o$ cellulose acetate!pol%eth%lene

    gl%col membranes $or reverse osmosis

    &"nan &hma"a''Si"ra ahee"

    a'Shaha"*a+soo" ,han

    a'Saba" e-.ul

    a'*uhamma" Sha/+

    a' *uhamma" aroo+

    b',hairu""inSanaullah

    c' ahir 2amil

    a

    aDepartment o$ ol%mer #ngineering an" 1echnolog%'4niversit% o$ the unjab'uai"-e-&am Campus' 6ahore 57580'a9istan

    bnstitute o$ Chemical#ngineering an" echnolog%' 4niversit% o$ the unjab' uai"-e-&am Campus'6ahore 57580'a9istan

    cDepartment o$ Chemical#ngineering an" #nerg% Sustainabilit%'4niversit% *ala%sia Sarawa9'87300 ,otaSamarahan'Sarawa9'*ala%sia

    ; . ; 6 . ; S

    2-stage phase inversion protocol< involving S an" controlle" evaporation

    Silica is use" as an a""itive to augment permeation per$ormance

    &""ition o$ silica enhance" the $ouling resistance remar9abl%

    =ptimum loa"ing o$ silica particle is re+uire" $or ma>imumper$ormance

    a rt i c l e i n $o

    &rticle histor%:

    ?eceive" 23 ul% 2017

    ?eceive" in revise" $orm 2 =ctober

    2017

    &ccepte" @ =ctober 2017

    &vailable online >>>>

    ,e%wor"s: ?everse

    osmosis

    ol%eth%lene

    gl%col Cellulose

    acetate Silica

    hase inversion

    a b s t ra c t

    n this wor9' a series o$ cellulose acetate!pol%eth%lene gl%col-@00 membranes' with var%ing ratios were

    prepare" b% 2-stage phase inversion protocol he permeation properties were stu"ie" b% subjecting

    membranes in in"ig- enousl% $abricate" reverse osmosis plant &$ter optimiation o$ "i$$erent C&!#. ratios'

    the membrane with highest salt rejection capacit% was selecte" an" mo"i/e" with var%ing amount o$ silica

    he *o"i/e" membranes were characterie" $or their permeation properties' h%"rophilicit%' compositionalanal%sis' thermal stabilit%' mechanical strength an" morphological stu"ies Silica signi/cantl% inAuence" the

    permeation per$ormance o$ composite membranehe Au> enhance" $rom 035 to 27@ 6!h m2

    along with an

    1171B relative increase in salt rejection he h%"rophilicit% was signi/cantl% enhance" b% the a""ition o$

    silica n 01:? spectra' the broa"ening o$ thepea9 aroun" 3500 cmC1

    an" emergence o$pea9 at 850 cmC1

    speci/e" the incorporation o$ silica particles he thermal anal%sis in"icate" the relative increase in

    "egra"ation temperature (ma>) an" glass transition tempera- ture (g) $or CS-5 membrane he

    mechanical stabilit% o$ the mo"i/e" membranes' increase" initiall%' but "ecline" with $urther a""ition o$

    silica he results in"icate" that the incorporation o$ Si=2 content in the casting solution improve" the $ouling

    resistance o$ the membranes

    2017 #lsevier EF &ll rights reserve"

    1 ntro"uction

    *embranes an" membrane processes subsist as ol" as li$e G17H?ecentl%' s%nthetic membrane processes have appeare" among the

    most innovative technologies to attain a variet% o$ goals ranging

    $rom molecular separation to concentration o$ pro"ucts G5H he

    intrinsic characteristics o$ membranes li9e high e$/cienc%' simplicit%'

    selectivit%' low energ% consumption an" goo" stabilit% ma9e

    membranes as an integral part o$ various chemical in"ustries G@'IH

    *embrane base" "esalination processes involve reverse osmosis

    (?=)' electro "ial%sis' $orwar" osmosis' ultra/ltration an"

    nano/ltration GJ'8H he ?= process was commercialie" in 18I0

    an" to"a% it is a

    Correspon"ing author el: K82 321@IJ8I82 (Cell)

    #-mail a""ress: a" nan ah me "b aloc hL gm ailcom (& &hma")

    lea"ing membrane technolog% representing J0B o$ total "esalination

    plants G1012H

    &n i"eal ?= membrane shoul" possess the resistance to chemical

    attac9' e>cellent separation per$ormance' goo" mechanical an"

    thermal stabilit% G13H he per$ormance o$ a membrane is notabl%

    inAuence"b% its constituents' which a$$ect man% properties G17'15H

    Farious pol%mers have been use" to s%nthesie membranes' but

    cellulose acetate (C&) membranes are well accepte" "ue to their goo"

    transport characteristics' low protein a"sorption' e>cellent water

    a$/nit%' appropriate mechanical strength' e>cellent /lm-$orming

    properties an" lower cost G1@'1IH ;ow- ever' C& has poor thermal

    stabilit%' lower chemical resistance' in$erior mechanical strength an"

    vulnerable to $ouling resistance here$ore' at- tempts have been

    ma"e to improve the per$ormance o$ C&b% "eveloping h%bri" organic

    inorganic membranes ew researchers have investigat- e" the e$$ect

    o$ alumina (&l2=3)' irconia (Mr=2)' titania (i=2)'silver

    h ttp :!!" >" oio rg !1 010 1 @!j" e s al2 0 1 71 0 0 0 7

    0011-81@7! 2017 #lsevier EF &ll rights reserve"

    http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://www.sciencedirect.com/science/journal/00119164http://www.sciencedirect.com/science/journal/00119164http://www.sciencedirect.com/science/journal/00119164http://www.sciencedirect.com/science/journal/00119164http://www.sciencedirect.com/science/journal/00119164http://www.sciencedirect.com/science/journal/00119164http://www.sciencedirect.com/science/journal/00119164http://www.sciencedirect.com/science/journal/00119164http://www.elsevier.com/locate/desalhttp://www.elsevier.com/locate/desalhttp://www.elsevier.com/locate/desalhttp://www.elsevier.com/locate/desalhttp://www.elsevier.com/locate/desalmailto:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004http://www.sciencedirect.com/science/journal/00119164http://www.elsevier.com/locate/desalhttp://www.elsevier.com/locate/desalmailto:[email protected]://dx.doi.org/10.1016/j.desal.2014.10.004http://dx.doi.org/10.1016/j.desal.2014.10.004
  • 8/10/2019 Effect of Silica on the Properties of Cellulose Acetatepolyethylene

    2/15

    2 & &hma" et al ! Desalination 355 (2015) 1N

    *embrane

    t%pe

    ater

    content

    (B)

    lu>

    (6!h m2)

    Salt rejection

    (B)

    *embrane

    permeabilit%

    (O10C7

    6!h m2

    9a)

    C&!#.-1 @150 0JI 5200 2I0

    C&!#.-2 5JI0 0I0 @000 250

    C&!#.-3 5385 07@ @820 200

    C&!#.-7 5111 035 J150 1@J

    (Control)

    ig 1 & schematic o$ reverse osmosis rig

    an" silica (Si=2) particles in various pol%meric materials G1J20Hhe

    re- sultant h%bri" membranes have been reporte" to increase the

    Au> an" mechanical strength' upon increasing the concentration o$

    inorganic par- ticles G21'22H Si=2 particles have attracte" particular

    attention owing to their special properties li9e small sie' thermal

    resistance' /ne suspen- sion $ormation in a+ueous solution' strong

    sur$ace energ% an" relativel% inert material

    ol%meric ?= membranes are s%nthesie" through phase

    inversion protocol t is the most versatile techni+ue to obtain a

    variet% o$ mor- phologies ranging $rom micro/ltration membranes

    with ver% porous structures' to more "ense reverse osmosismembranes G23H he concept

    able 1

    #$$ect o$ concentration o$ C&!#. on water content' Au>' salt rejection an" membrane

    permeabilit%

    o$ phase inversion involves an arra% o$ "i$$erent metho"s such as

    "i$$usion-in"uce" phase separation' vapor-phase precipitation'phase

    inversion b% controlle" evaporation an" thermal-in"uce" phase

    separa- tion (1:S) G27H &ll the metho"s involve comple> multi-

    component

    ig 2 ?elationshipbetween pressure an" Au>

  • 8/10/2019 Effect of Silica on the Properties of Cellulose Acetatepolyethylene

    3/15

    mass trans$er e>cept thermal-in"uce" phase separation which

    primari- l% "epen"s on heat trans$er G25H

    n this paper' a "etaile" stu"% towar"s the s%nthesis o$ thermo-

    able 2

    #$$ect o$ "i$$erent concentration o$ silica on water content 'Au>' salt rejection an"

    membr ane perme abilit%

    mechanicall% en"urable membranes is reporte"hese membranes

    were prepare"b% using cellulose acetate'pol%eth%lene gl%col an"

    silica

    *embrane

    t%pe

    ater

    content (B)

    lu>

    (6!h m2)

    Salt rejection (B) *embrane permeabilit%

    (O10C7

    6!h m2

    9a)

    & 2-stage phase-inversion protocol was "evise" involving thermall%-

    in"uce" phase inversion $ollowe"b% a controlle" evaporation proce-

    "ure he chemical alteration' thermal stabilit%' mechanical strengthan" morphological structure o$ membranes were characterie" b%

    attenuate" total reAectance-ourier trans$orm in$rare" spectroscop%

    (&?-?)' thermogravimetric anal%sis (.&)' "i$$erential scanning

    calorimetr% (DSC)' ultimate tensile strength an" scanning electron

    microscop% (S#*) respectivel% he e$$ects o$ a""ition o$ Si=2

    particles on the membrane properties were investigate" b%

    e>amining thepermeation per$ormance' such as pure water Au> an"

    solute rejection e reporte" here that the incorporation o$ silica

    particles simultaneousl% improves the selectivit% an" permeabilit% o$

    membranes

    2 *aterials an"

    metho"s

    Cellulose acetate (C&' *w 30'000 an" acet%l content 38B)'

    pol%eth%l- ene gl%col-@00 (#.) an" acetone were supplie" b% ED;

    laboratories supplies' oole' #nglan" Silica (Si=2) was purchase"

    $rom Sigma &l"rich (#nglan") &ll chemicals an" solvents o$

    anal%tical gra"e were use" as receive"

    21 reparation o$ "ope"solutions

    10 g o$ C& was "issolve" in J0 m6o$ acetone with constant stirringat

    J0 PC $or 2 h o this homogenous solution' 10 g o$ #. was a""e"

    with regular stirring at J0 PC $or @ h he viscous an" clear solutionwas obtaine"' which was terme" as a blen"e" "ope" Solution'

    C&!#.-1 G2@H he "i$$erent ratios o$ C&!#. (12!J' 17!@ an" 1@!7

    g!g) were use" to prepare three a""itional "ope" solutions'labele"

    as C&!#.-2' C&!#.-3 an" C&!#.-7 respectivel% he casting

    solutions were allowe" to cool "own to room temperature (25 PC)

    an" were 9ept $or

    27 h in a seale" Aas9 to remove micro bubbles $orme" in thesolution

    CS-1 5J11 12J J300 31J

    CS-2 @@I1 178 J550 350

    CS-3 I533 1I8 J850 705

    CS-7 J033 208 8200 783

    CS-5 J22I 27@ 8000 532

    3 Characteriation

    31 *embrane per$ormance

    311 #>perimental set up o$ ?= rig

    he permeation e>periments were carrie" out in the ?=

    e>perimen- tal rig using a plate an" $rame membrane mo"ule &

    schematic o$pro- cess Aow "iagram $or aplate an" $rame membrane

    mo"ule is shown in ig 1 t consiste" o$ the $ee" tan9 o$ 10 6

    capacit% he temperature o$ the $ee" solution was in"icate" an"

    controlle" b% a thermocouple an" controller setup he $ee" was

    circulate" using a circulationpump with a ma> power rating o$ 1 9

    at a ma> $ee" rate o$ 2500 6!min he e$$ective membrane area in

    contact with the $ee" was 001J m2 hepermeate was collecte" $rom

    the sample points provi"e" a$ter the membrane mo"ule & saline

    solution (QaCl solution) having a con"uc- tance o$ 20 milli-siemens

    (mS) an" a concentration o$ 10 g!6 was sub- jecte" to the $ee" tan9

    #ach membrane was compacte" with "istille" water at I00 9a $or 5

    h till it attains stea"% state ee" temperature was 9ept at 30 PC

    "uring the operation

    312 ater content

    he abilit% o$ membranes to absorb water was "etermine" a$ter

    soa9ing membranes in water $or 27 h an" weighing a$terwar"she

    wet membranes were then place" in a vacuum "r%er at I5 PC $or 7Jh an" the weights o$ the "r% membranes were recor"e" G28H he

    water content'absorbe" b% the membranes'was "etermine" b% the

    $ollowing relation'

    wCD22 Casting o$ membranes ater content RBS T U100 R1S

    D

    he "ope" solution was sprea" slowl% on glass plate b%

    maintaining uni$orm thic9ness with the help o$ micrometer a"justable/lm applicator (?e$: 111I!300 Sheen instruments) he temperature

    o$ caste" mem-branes was lowere" imme"iatel% to 0 PC $or 15 min

    to in"uce (S) he S causes the $ormation o$ "ense an"

    as%mmetric structure t was $ollowe" b% precipitation un"er

    controlle" evaporation b% increas- ing temperature up to @0 PC G2IH

    he s9inne" membranes' thus $orme" G2JH were care$ull% remove"

    $rom the glass plates b% using a sharp 9ni$e he thic9ness o$ the

    resulting membranes was measure" an" was $oun" in the range o$

    50200 microns hese membranes were test- e" on the basis o$ their

    permeation per$ormance an" the best per$orming C&!#.-7 (control)

    membrane was selecte" $or $urther mo"i/cation with silicaparticles

    23 *o"i/cation o$ "ope" solutions

    Silica (15B' w!v) was "isperse" in al9aline solution (10 m6)

    be$ore a""ing to the C&!#.-7blen"e" "ope solution with constant

    stirring $or 2 h at J0 PC he membranes (CS-1CS-5) were caste"

    an" "rie" $ollowing the same proce"ure as mentione" in Section

    22 Control an" mo"i/e" membranes were transparent' Ae>ible an"clear with smooth sur$ace

  • 8/10/2019 Effect of Silica on the Properties of Cellulose Acetatepolyethylene

    4/15

    where w is wet sample weight an" D is "r% sample weight

    ig 3 lu> o$ control an" mo"i/e" membranes over time

  • 8/10/2019 Effect of Silica on the Properties of Cellulose Acetatepolyethylene

    5/15

    p

    ig 7 Droplet images on control an" mo"i/e"membranes

    313 ermeate Au> ()

    he permeate Au> () represents the amount o$ pure water

    collecte" per unit time an" per unit area at variable pressures t wascalculate" b% G30H:

    317 Salt rejection

    n reverse osmosis' the solute or salt rejection is "e/ne" as the

    ratio o$ the concentration "i$$erence across the membrane an"

    e>presse" as G31H'

    2 T Vt & R2S?RBST 1C VC

    > 100 R3S

    where 2 is the permeate Au> (6!h m2)' is the amount o$permeate

    (6)'t is the time (h) an" & is the membrane area (m2)

    where ? is the salt rejection (B)' Cppermeate an" $ee" respectivel%

    an" C$ are the con"uctance o$

    ig 5 Contact angle o$ control an" mo"i/e" membranes ig @ ? spectra o$ control an" mo"i/e" membranes

  • 8/10/2019 Effect of Silica on the Properties of Cellulose Acetatepolyethylene

    6/15

    *embrane

    %pe

    1min

    (PC)

    1ma>

    (PC)

    eight loss

    at 1ma> (B)

    ?esi"ue at

    en" (B)

    Control 2I0 700 JIJ5 1CS-1 300 7@0 J818 5@J

    CS-2 330 7J0 J817 5I7

    CS-3 370 500 J817 5J0

    CS-7 350 510 J817 582

    CS-5 3@0 520 J817 @I2

    ig I .& curves o$ control an" mo"i/e" membranesig J Derivative weight loss o$ control an" mo"i/e" membranes

    35 hermal anal%sis

    32 *embrane

    permeabilit%

    *embrane permeabilit% in"icates the tolerance o$ membrane

    towar"s h%"raulic pressure o "etermine m' the Au> was measure"

    at "i$$erent trans membrane pressures (W) he pressure "uring the

    operation was increase" $rom 750 to J00 9a he permeabilit% o$

    the membrane was evaluate" $rom the slope obtaine" b% plotting

    permeate Au> versus membrane pressure "i$$erence (W)'using #+

    (7)

    2m T

    WR7S

    where m is the membrane h%"raulic permeabilit% G6 hC

    mC 2

    !9aH

    an"W is a pressure "i$$erence(9a)

    33 Contact anglemeasurement

    he contact angles were measure" b% a Drop Shape &nal%er

    (DS&

    30' ,?4SS .erman%) through sessile "rop metho" & "angling

    "roplet o$ 5 X6 o$ "eionie" water was "roppe" care$ull% $rom -

    shape" micro- s%ringe to membrane sur$ace he contact angles

    were calculate" b% the so$tware #ach contact angle was measure" at

    ten "i$$erent points o$ each membrane an" an average value was

    calculate" G32H

    37 ourier rans$orm in$rare" spectroscop%(1:?)

    01:? o$ membranes was scanne" b% using a Shima"u:? restige-

    21 e+uippe" with ;oriontal &ttenuate" otal ?eAectance (;&1?)

    acces- sor% he e>periments were run with air as the bac9groun"

    or each spectrum 100 scans were accumulate" with a resolution o$ 7

    cmC1

    able 3

    1hermal Stabilit% o$ control an" mo"i/e"membranes

    Di$$erential scanning calorimetr%!thermal "egra"ation

    measurements o$ the membrane samples were per$orme" using 1&

    instruments SD- @00 thermo gravimetric anal%er at a heating rate

    o$ 10 PC!min an" temperature programs $or DSC were run $rom 30 PC

    to J00 PC he ther- mograms $or 1.& were obtaine" using a c%cle o$

    heating $rom an ambient temperature to J00 PCQitrogen Aow was

    maintaine" at 15 m6!min in or"er to remove all corrosive gas

    involve" in the "egra"ation

    3@ *echanical stabilit%

    ensile testing o$ membranes was per$orme" at room

    temperature using an :nstron-t%pe tensile testing machine

    (1estometric!*350-10C1 ?=C;D&6#' #nglan")with a crosshea" spee"

    o$ 3 mm!min he sample wi"th was 25 mm an" the length between

    the jaws was 75 mm he measurements were per$orme" at 25 PC an"25 Y 2Brelative humi"it%

    3I Scanning electron microscop% (S#*)

    Scanning electron microscop% was per$orme" on eol S*-@7J0

    1he membranes were cut into small pieces an" place" on stub an"

    9ept in a speci/c chamber in a vacuum he electron beams were

    sputtere" on sample an" images o$ membranes on var%ing resolutions

    were observe"

    ig 8 DSC curves o$ the control an" mo"i/e" membranes

  • 8/10/2019 Effect of Silica on the Properties of Cellulose Acetatepolyethylene

    7/15

    silica amount he relative increase in water content is 3IJJB he *embrane t%pe S (*pa) #b (B) Containcrease" water content ma% be "ue to the increase in membrane h%"ro-

    Control 2@387 5J 5721hilicit since the hi h h "ro hilicit $acilitates the "i$$usion o$ water

    molecule into the membrane Similarl%' the Au> o$ all mo"i/e" mem- CS-2 35555 JI3 7011

    branes also increase" with the increase in silica content CS-5 membrane CS-3 717@7 113@ 3718

    has hi hest Au> o$ 27@ 6!h m2Similar results have been obtaine"b Zin CS-7 73I2J 1223 2J@8

    7 ?esults an" "iscussions

    71 *embrane per$ormance

    he Au> o$ all "ope" an" compacte" membranes was calculate" at

    a pressure o$ @50 9a $or I h he water content' Au> an" salt

    rejection were measure" b% using #+s (1)' (2) an" (3) respectivel%

    he water content' water Au>' salt rejection an" membrane

    permeabilit% are represente" in able 1 C&!#.-1 membraneshowe" a ma>imum Au> o$ 0JI 6!h m

    2while it e>hibite" minimum

    salt rejection capacit% o$

    52BC&!#.-7 membrane ha" J15B salt rejection an" its Au> was

    035 6!h m2

    he C&!#.-1 membrane' with the highest water content an"

    Au>' showe" re"uction in salt rejection capacit% while C&!#.-7

    membrane with the lowest water content an" Au>' ha" an elevate"

    salt rejection capacit% as in"icate" in able 1 t was observe" that

    with the increase" content o$ cellulose acetate' the water content'

    Au> an" membrane permeabi lit% was "ecrease" while the salt

    rejection capacit% was increase" remar9abl%

    he transport mechanism within membrane can best be

    e>plaine" on the basis o$ the solution "i$$usion mo"el &ccor"ing to

    thismo"el' transport'

    process within

    themembrane involves three

    steps: sorption at the sur$ace o$ the membrane'"i$$usion into "ense

    membrane un"er pressure an" then "esorption he h%"rophilic

    nature o$ #. acte" as "riving $orce $or sorption o$ water into

    membrane G333@H 1he "ecrease in water content was attribute" to

    the "ecrease in h%"rophilic #. content

    t was "e"uce" pragmaticall% that salt rejection was inversel%

    relate" to salt passage Cellulose acetate being "esalting in nature was

    responsi- ble $or the removal o$ salt G3IH his was a reason that

    C&!#.-7 ha" ma>imum salt rejection abilit% hen salt rejection

    e$/cienc% o$ mem-brane was at its best' at the same time Au> was

    re"uce"' "epen"ing upon the var%ing amount o$ C& an" #.

    #. is h%"rophilic in nature an" acts as pore $ormer G3JH C&!#.-

    1 membrane' with ma>imum +uantit% o$ #.' showe" increase in

    water Au>' but at the same time salt rejection was compromise" his

    might be attribute" to the $ormation o$ macro voi"s G38H onmembrane which allowe" the passage o$ salt along with water

    *oreover' the "i$$usion rate o$ water was accelerate" b% the

    presence o$ #. "ue to its h%"rophilic nature #. increase" the

    ten"enc% o$ pore $ormation an" as a conse+uence Au> was increase"

    t was observe" that within the pressure range o$ 750 to @50 9a'

    the Au> "ecrease" linearl% with increase in trans membrane

    pressure as in"icate" in ig 2 hese results are in agreement with

    the reporte" "ata G70H

    he "ecline o$ Au> with the passage o$ time' even at high pressure

    was attribute" to the compaction phenomena occurring on the

    mem- brane sur$ace he compaction o$ membrane un"er pressure

    involve" rearrangement o$pol%meric chains which le" to the change

    in mem- brane structure with low value porosit% which conse+uentl%

    "ecrease" the Au> Similar results were obtaine" b%&rthanareeswaranet al G3JH

    =n the basis o$ salt rejection an" Au>' C&!#.-7 membrane was

    selecte" $or mo"i/cation with silica &$ter mo"i/cation these

    membranes were characterie" an" compare" with C&!#.-7

    (control) he water content' Au>' salt rejection an" membrane

    permeabilit% o$ mo"i/e" membranes are given in able 2

    he water content o$ the membrane was relate" to the

    h%"rophilic- it% o$ the membrane able 2 in"icates that the water

    content an" mem- brane permeabilit% o$ mo"i/e" membrane

    increase" with increase in

    ig 10 1ensilestress an" elongation-at-brea9 o$ control an" mo"i/e" membrane

    that a""ition o$ silica nanoparticles increases the Au> G71H he

    embe"- "ing o$ silica particles in C&!#. membrane can also "isrupt

    the pol%mer chain pac9ing b% creating microporous "e$ects between

    inorganic particle an" pol%mer inter$ace he salt rejection increase"

    $rom J15B to 82B $or CS-7 membrane as a result o$ incorporation o$

    silica particles G72H ;ow- ever' a slight "ecrease was observe" at

    highest silica loa"ing (5B w!v) his result can be attribute" to the

    agglomeration o$ silica particles in certain locations which a$$ect the

    solute rejection

    711 &nal%sis o$ membrane $ouling "uringpermeation

    norganic compoun"s can be a"sorbe" an"!or "eposite" on the

    membrane sur$ace' causing membrane $ouling which in turn re"uce

    the Au> "rasticall%ouling increases energ% consumption an" results

    in high operating cost G72H ig 3 shows the permeation Au> o$

    control an" mo"i/e" membranes t is attention-grabbing that Au> $or

    the con- trol "ecline" with the passage o$ time an" attain a stea"%state' whereas $or the mo"i/e" membranes' the Au> increase"

    remar9abl% with the increase o$ Si=2 content he increase in

    permeation Au> was "ue to the increase in sur$ace h%"rophilicit%

    which was ren"ere" b% Si=2 particles Similar observations were

    ma"e $or C&!Si=2blen" membranes $or ultra/ltration application G28H

    72 *embrane h%"raulic permeabilit%

    (m)

    *embrane h%"raulic permeabilit% is an intrinsic resistance o$ the

    membrane t was "etermine" b% subjecting the membranes to

    various pressures (750' 500' 550' @00' @50' I00' I50 an" J00 9a) an"

    the m value was calculate" $rom the slope o$ the linear relationship

    betweenpressures versus Au>he permeabilit% o$ unmo"i/e" membranes is given in able 1

    1he presence o$ #. ha" consi"erable e$$ect on the h%"raulic

    permeabilit% hus' when the #. concentration was "ecrease"

    $rom 10 to 7 gm in the "ope solution' there was a correspon"ing

    "ecrease in h%"raulic per- meabilit% $rom 2I0 to 1@J (O10C7

    6!h m2

    9a) t might be attribute" to the "isappearance o$pores which were

    $orme"b% #. *oreparticularl%'

    able 7

    *echanical properties an" contact angle o$ control an" mo"i/e"membranes

    ct angle [ ("eg)

  • 8/10/2019 Effect of Silica on the Properties of Cellulose Acetatepolyethylene

    8/15

    et al $or silica incorporation inpol%ami"e membranes' whichreveale"

    CS-5 3J27@ 1033 2710

  • 8/10/2019 Effect of Silica on the Properties of Cellulose Acetatepolyethylene

    9/15

    C&!#.-1 membrane with the highest #. contents o$$ere" greatest

    permeabilit% his result was in agreement with that o$ Au> obtaine"

    through permeation e>periment

    he m values $or the mo"i/e" membranes are given in able 2'

    showing an increase with the increasing amount o$ silica $rom 1 to

    5B w!v or the mo"i/e" membranes' the permeabilit% increase"

    $rom

    12J to 27@ (O 10C 7

    6!h m2

    9a) he increase in permeabilit%

    resulte"in an increase in permeate Au> as in"icate" in able 2 t was mainl%

    "ue to increase in membrane h%"rophilicit% with the incorporation

    o$ silica particles which e>pe"ites "i$$usion an" solubiliation o$

    membranes

    73 Contact angle

    he contact angle is an important parameter $or measuring

    sur$ace h%"rophilicit% n general' a smaller contact angle

    correspon"s to a more h%"rophilic material ig 7 represents "igital

    image o$ a li+ui" "roplet on a "r% sur$ace o$ all membranes in which

    the contact angle ([) is measure" accor"ing to the sessile "rop

    metho" t is evi"ent $rom ig 5 that there is "ecrease in contact

    angle b% increasing silica particle concentration hese results

    "emonstrate" that silica particle can improve h%"rophilicit% o$

    membrane he less h%"rophilic sur$ace shows larger contact angle

    with the sur$ace an" vice versa

    77 01:? anal%sis

    Spectroscopic metho"s pla% a crucial role in pol%mer

    characteria- tion he use o$ metho"s such as in$rare" spectroscop%

    is essential in or"er to investigate molecular structure o$ membranes

    01:? spectrums o$ the control an" mo"i/e" membranes are given in

    ig @

    n case o$ control'pea9 at 37@8 cmC1

    represente" stretching o$

    =\;' 2JII cmC 1 showe" stretching o$ C\; bon"' 1I38 cm

    C 1

    "epicte" the strongpea9 $or C]=o$ carbon%ls'1733 cmC1

    in"icate"

    ben"ing o$ C\; $ollowe" b% pea9s at 13@8 cmC 1

    an" 1227 cmC 1

    which "escribe" roc9ing an" wagging mo"e o$ C\; bon" he

    strongest pea9 at

    1035 cmC1

    speci/e" C\=\Cwhilepea9 at 1112 cmC1

    an" 807 cmC

    1

    illustrate" the presence o$ sacchari"e Similar results ha" been previ-

    ousl% reporte" in the literature G73'77H he emergence o$ new pea9

    aroun" 850 cmC1

    in the spectra o$ all mo"i/e" membranes coul" be

    attribute" to stretching vibration o$ Si\=\ he broa"ening o$pea9

    aroun" 32003@50 cmC 1

    was "ue to ;-bon"e" Si\=; G75H he

    broa"- ening an" emergence o$ new pea9 in the spectra o$ mo"i/e"

    membranes con$orm the impregnation o$ silica particles within the

    membrane matri>

    75 hermal anal%sis

    he thermal "ecomposition is e>presse" in terms o$ weight loss as

    a $unction o$ the temperature $or the control an" mo"i/e"

    membranes as shown in ig I #ach 1.& curve shows three main

    "egra"ation steps he /rst step too9 place between 30 PC an" 250

    PC an" "ispla%e" about 35B o$ weight loss his "egra"ation was

    associate" with the vol- atiliation o$ the volatile matter an"!or the

    evaporation o$ resi"ual absorbe" water he secon" stage o$"egra"ation starte" $rom 2@0 PC an" continue" up to 700 PC here

    was JIJ5B weight loss occurring in secon" stage "ue to

    "egra"ation o$ cellulose acetate chain he temperature at which

    ma>imum "egra"ation occurs (ma>) is 700 PC Similar results were

    observe" b% &rthanareeswaran et al G7@H 1he thir" step' starte" at

    700 PC s%mbolie" the carboniation o$ "egra"e" pro"ucts to ash

    t was observe" that the temperature at which "egra"ation

    initiate" (min) is relativel% higher $or all the mo"i/e" membranes as

    in"icate" in able 3 Similarl%' 1ma> $or all the membranes shi$te"

    towar"s higher temperature (700 PC to 520 PC)' with increasing

    amount o$ silica he substantial increase in thermal stabilit% was "ue

    to the incorporation o$ silica within the matri> o$ cellulose acetate or

    all the mo"i/e" mem- branes' when the temperature e>cee"e"

    higher than 550 PC' the mass remaine" almost constant' whichshowe" that the resi"ue was mostl% metal o>i"e G7IH whereas in case

    o$ control sample 1Bresi"ue in"icates the presence o$ carbon ash

    he /rst "erivative o$ the mass-change with respect to time

    ("m!"t' calle" "erivative thermogravimetr% (D.)) was calculate"

    an" plotte" as a $unction o$ temperature (0ig J) 4sing D.

    anal%sis' a series o$ pea9s were obtaine" instea" o$ stepwise .

    curves he areas un"er the pea9s were proportional to the total

    mass-change o$ the membrane sample he D1. is more precise in

    showing the onset o$ a reaction that is accompanie" b% mass loss an"

    also permits the reaction temperatures to be "e/ne" more precisel%

    he D.pea9s are associate" with the onset o$ the secon" stage o$

    "ecomposition hese pea9s shi$te" towar"s higher temperature'

    which in"icates an increase in stabilit% o$ mo"i/e" membranes

    7@ DSC stu"ies

    n a DSC anal%sis' the glass transition temperature (g) is an

    in"ica- tive o$ the structure an" pac9ing o$ the pol%mer chain in the

    membrane & lower glass transition temperature (g) in"icate" that

    the membrane possesse" more $ree volume an" there$ore a loose

    structure G73H he DSC thermogram o$ control an" mo"i/e"

    membranes are given in ig 8 t was observe" that the control

    e>hibite" a 1g at @0 PC t was

  • 8/10/2019 Effect of Silica on the Properties of Cellulose Acetatepolyethylene

    10/15

    ig 11 S#* images o$ control (a) top sur$ace an" cross-section (b)

  • 8/10/2019 Effect of Silica on the Properties of Cellulose Acetatepolyethylene

    11/15

    interesting to note that 1g o$ mo"i/e" membranes'increase" $rom @5

    to

    J0 PC CS-7 membranes reveale" 1g o$ J0 PC he increase in 1g was

    "ue to the inclusion o$ silica within C&!#. membrane Similar

    results were suggeste"b%Qunes et al G7JH he increase in 1gresulte"

    in higher pac9ing "ensit% an" rigi"it% hese results were in

    agreement with the mechanical properties o$ membranes

    7I *echanicalstabilit%

    n or"er to investigate the e$$ect o$ silica on mechanical properties

    o$ membranes' the tensile stress (S) an" elongation-at-brea9 (#b) o$

    con- trol an" mo"i/e" membranes were measure" an" shown in ig

    10 :t was noteworth% that the elongation-at-brea9'tensile stress an"

    Zoung s mo"ulus initiall% increase" with the a""ition o$ Si=2

    particles an" reache" at pea9 when the Si=2particle concentration

    was 7B (w!v) an" then "ecline" as the Si=2 particle

    concentration was $urther increase" Zan et al ma"e similar

    observations $or &l2=3!FD0blen" $or

    4 membrane he initial increase ma% be "ue to increase in

    interaction between the silica particles an" pol%mers ;owever' an

    e>cessive concen- tration ma% cause the aggregation o$ particles an"

    prevent it to "isperse uni$orml% in a pol%meric matri> he large

    phase separation results in the "ecline o$ mechanical stabilit% o$ the

    membrane G78H hese behav- iors in"icate that an appropriate

    amount o$ Si=2 particles in C&!#.-7 solution can improve the

    mechanical properties o$ the membrane

    he salt rejection an" mechanical behavior o$ mo"i/e"

    membranes showe" i"entical pattern ie with increasing silica

    particles there was increase" in salt rejection in a""ition to

    mechanical strength Eut at ma>imum loa"ing o$ silica particles'

    there was "ecline in salt rejection as well as mechanical behavior as

    shown in ables 2 an" 7

    7J S#* anal%sis

    o attain high per$ormance membranes $or speci/c applications'it

    is essential to manipulate the morphological structures o$ the

    membranes

  • 8/10/2019 Effect of Silica on the Properties of Cellulose Acetatepolyethylene

    12/15

  • 8/10/2019 Effect of Silica on the Properties of Cellulose Acetatepolyethylene

    13/15

    here$ore' the morphological stu"ies o$ various sections o$ control

    an" sur$ace mo"i/e" membranes were ma"e b% using scanning

    electron microscope he scanning electron micrographs o$ C&!#.

    blen" mem- brane are shown in ig 11 t reAects the "ense

    as%mmetric composite structure' with top' s9inne"-la%er an" sub-

    la%er

    ig 12 (a$) represents the images o$ mo"i/e" membranes with

    "i$$erent silica loa"ings &ccor"ing to S#* images' the sur$ace

    morphol- ogies o$ the membranes were change" signi/cantl% with thea""ition o$ silica particles he top sur$ace morpholog% is shown on

    ig 12(a) t was observe" that micro-sie silica particle (051 Xm)

    were "istribute" in the membrane he interaction o$ silica

    particles with pol %mer "isrupts the mobilit% o$ pol%meric chains

    resulting in the $ormation o$ macroscopic "e$ects G28H Eut as

    concentration increase" the "e$ects were /lle" with silica aggregates

    as observe" in ig 12($)

    5 Conclusions

    n this stu"%' thermo-mechanicall% stable membranes were

    s%nthe- sie" through a 2-stage phase inversion metho"& series o$

    C&!#. blen"e" membranes showe" a change in Au> an"

    permeabilit% with change in ratio o$ #. an" C& he membranewith optimum Au> an" salt rejection was selecte" $or mo"i/cation

    with silica he mo"i/e" membranes resulte" into an improve"

    tren" in the salt rejection an" permeation properties CS-7 ha" 82B

    salt rejection which provi"e" almost 11B increase in salt rejection

    capacit% compare" with the control membrane (J15B) he

    mechanical stabilit% o$ the mo"i/e" mem-branes'increase" $rom 1

    to 7B (w!v) o$ silica loa"ing urther increase in Si=2particles in the

    casting solution resulte" in the "ecrease o$ tensile strength an"

    elongation at brea9 Similarl%' 1ma> an" 1g o$ all mo"i/e" membranes

    remar9abl% increase" as evi"ent $rom 1.& an" DSC anal%sis he S#*

    images reveale" incorporation o$ silica particles within the

    as%mmetric composite membrane he improve" h%"rophilicit% o$

    the composite membrane also enhance" $ouling resistance his

    stu"% showe" a critical nee" $or optimiing the silica particleloa"ing' as overloa"ing o$ silica ma% not be a"vantageous $or ?=

    per$ormance an" has negative impact on the ?= membrane

    properties

    &c9nowle"gments

    he authors e>press their cor"ial gratitu"e to the team o$

    Department o$ ol%mer #ngineering an" echnolog%' 4niversit% o$ the

    unjab' $or their co-operation "uring the e>ecution o$ this research

    projecthe au- thors are also than9$ul to the 4niversit% o$ *ala%sia

    Sarawa9 (4Q:*&S)' which supporte" this wor9 through grant D

    G.rant re$ no 02 (D23)!

    888!2013(0@)H

    ?e$erences

    G1H 6an g ' 2 Shen ' Z Mhan g ' Z Z u ' Z . u o ' C 6i u ' r ep arat i o n an " charac teriations

    o $ charge " p ol% ( vin%l but% r al ) h o l lo w / be r u ltra / l t ra t io n m e mb r ane s w i th

    p e r A u oros ul $o n i c a c i " a s a" "iti ve ' 2 *emb rS c i 73 0 (20 1 3 ) 110

    G2H ; Str athmann ' 6 . l o m o ' # D r ioli' & n nt r o " uctio n t o * e mbran e S c ien c e an"

    e c hno l o g% ' Co nsi glioQ a i o n a l e D e l l e ?i ch e r c h e ' ta l% ' 2 00@

    G3H . e nte n'* em b rS c i e c h n o l 27 (20 0 2 ) 1 00 81 0 2 7

    G7H S S eja l' ? De s ai ' o l% m er mem b ra n e te c hn olog%' n t #n g Sc i nn o v e c hn o l

    2 (2 01 3) 7 0 07 03

    G5H ; Stra thmann ' *embran e sep a rat i o nprocesses : curren t r elevanc e an " $uture

    opp ortu n i ti es ' &Ch # 2 7 I (2001 ) 10II10JI

    G@H ; S tra th m a n n' * e mb ra ne s ep a ra tio n p ro ce s s es' * e mb r S c i 8 (18 J 1 ) 1 2 1

    1 J8

    GIH ; St rath m an n' *em b ran e s an" mem b ra n e sep ara tion pro c ess e s' 1' r incip les'in

    4 llma n n s # n c % c lop e " ia o$ n " u st rial C he mistr%' ile % ' . e rm a n%' 2 012

    GJH ; , 6on s " ale' he g ro wt h o$ m e m b ra ne te c h n o log %' 2 * e m b r S c i 1 0 (1 8 J 2) J 1

    1 J 1 G8H EF Er u gg e n' D e sa lin a ti o n b% "is ti lla ti o n an" b% re v e rse o s mo s istr e n"s

    towa r"s

    th e $u tu re' * em br e c h n o l (20 0 3 ) @8

    G10H E F Erugg en' C Fa n " ec as tee l e' F .e s te l' D o% e n b' ? 6 e% s e n b ' & r e v i ew o$

    pre s sur e -"r iv en m e m b ra n e pr o ce s se s i n w a s te w a te r tr e a tme n t a n " " rin9 ing

    w a te r p ro " u c tio n' # n v iro n ro g 22 (20 0 3 ) 7 @5 @

    G11H C 0rit m a nn' 2 6o we nb erg' intg en s' * e lin' S ta te -o $-th e -a rt o $ re v e rs e

    os mo s is " e s a lin a tio n' D e s a lin a tio n 2 1@ (2 00 I) 1I @

    http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0040http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0040http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0040http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0040http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0040http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0040http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0040http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0040http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0040http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0040http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0040http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0025http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0005http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0030http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0035http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0040http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0040http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0045http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0050http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0055http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0060http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0065http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0070
  • 8/10/2019 Effect of Silica on the Properties of Cellulose Acetatepolyethylene

    14/15

    G12H 6 .re enle e a' D 6 a w l e r ' E D ree m an' E * a rro t' * ou lin ' ? e v e r se o sm osis

    "e s a lin a ti o n : w a te r s ou rce s' te c h n o l o g% a n " to"a%s c h a l le ng e s' a te r ? e s 73

    (2 0 0 8) 2 3 1 I2 37J

    G13H D 6 i' ; a n g' ?e ce nt " e v e lop m e n ts in re v e rs e osmo s i s " esa l i n ati o nm e m branes' 2 *ater Chem 2 0 (2010 ) 755175@@

    G17H , 6 e e ' 1 C &r not' D *atti a'& r evie w o $ r e vers e osmos i s membr a n e m a te r i a l s

    $or "esa l ina t io n"e v elop m e n t t o "a t e a n " $u t u r e p ote nt ial' 2 *e m br S c i

    3I0 (20 1 1 ) 122

    G15H *? .aru" ' SF ,ore ' FS ,ore ' S. ,ul9 ar ni ' & s h o r t r e v ie w o nproce s s an"

    applicatio n s o $ r e v e rs e osmosis ' 4 n i v #n v i ro n ? e s e chnol 1 ( 2011 ) 23 323J

    G1@H ?u stem e%e r';i s tor% o$ C& an" evo lut ion o$ the ma r9et s'*a c ro m ol S%mp 20J

    (2 0 0 7) 1@

    G1IH S 0isc he r', 1h ummle r' E F o l9 e rt' , ; e ttric h' S ch mi"t', is c h e r' rop e rtie s

    a n" app lic a tio ns o $ c e llu lo se a c e ta te' * a c ro m o l S % mp 2 @ 2 (20 0 J ) J 88 @G1JH S a u r o ia' ; & ru l ' F M E o s a 9 ' & Eu rb an' C F o ic e' * 6 Eruening'FF

    1a ra b a ra'#$$ecto $ / ller in c o rp o ra tion ro u te o n thep rop e rtie s o$p ol%s ul$on e-silv er n a n o c o mpo s ite m e m b ra n es o$ " i$$e re n t p o ro s itie s' 2 * e mb r S c i 3 2 5

    (2 0 0J ) 5 J@ J

    G18H * Ma$ar ' * &li' S* ,ha n ' 1 2amil'*M Eutt':nAuenc e o $ gl% co l a " "i tiv e s o n th e

    stru c- tur e an " per$ o rmanc e o $ cel lu lo s e a cetate! in c o>i" e blen " m e m b ranes '

    De salination

    2I 0 (2011 ) 8J107

    G20H D #ma"a" e h' 6au' *atsuura' * ?ahbari-Sisa9ht' & smail' & novel thin

    / lm c o mp o s ite $o rw a r" o s m o s is m e m b ra n e p rep a re" $rom S $ i= 2

    n an oc omp os ite s u b s tra te $o r w a ter " e s a lin a tio n' C h e m # n g 2 3 I (2 0 1 7) I 0J 0

    G21H . &rthanare e swarana' hani9aivela n' abrication o$ cellulose acetateirconia

    h%bri " me m brane s $o r u ltra / ltratio n app licat io n s :p er$orm an ce's tru c tur e an "

    $ouling a n a l%sis ' Sep u ri$ e c h nol I 7 (2010 ) 2 3 0235

    G22H Q * ara' 6 ra n ci s ' EF F e la m a 9 a n n i' & " " itio n o$ a lu m ina to c e ll u lo se

    a ce ta te m e mbran es' * emb rS c i 1 0 7 (1 8 8 5) 7 37 8

    G23H . Caneba ' DS Soong ' o l% me r membran e $ormati on throug h th e therm al-

    inve rs ion process 1 # >perim en ta l st u " % o $ m embran e s truc tur e $or m ation '

    *acro m olecule s 1J (1 8J5 ) 25 3 J257 5

    G27H D 6 i ' E ,r a n t' & ? . reen ber g'? 6 S ani' * e m b rane $o rm ati o n v ia ther mall%

    in"uc e " pha s e s epa r ation ( S): mo" e l " eve l opm e nt an" val i "at i on' 2 * embr

    S c i 2 I 8 (20 0 @ ) 5 0@ 0

    G25H ? , & r% a ' D r% ing in " u c e "p h a s e s ep a ra tio n in m u ltic o mp o n e nt p o l% m e ric c oatin gs

    s im u la tio n s tu "%' nt S c i e c h n o l ? e s 1 (2 0 1 2) 7 J5 3

    G2@H ;, 6 o n s " a le ' 4 * e rt e n' ? 6 ?i le% ' a % ' r a n sp o rt pr op e rtie s o$ c e ll u lo se

    a ce ta te o s m o tic m em bra ne s' &pp l o l% m S c i 8 (18 @ 5 ) 1 3 7 11 3@2

    G2IH & ? e u v e r s' C & Sm ol"e rs' or m a ti on o $ m e m b r a ne s b% m e a n s o$ im m e rsion

    pre c ipita t ion art he mecha n ism o$ $orma t ion o$ memb r anes prep are" $rom

    the s% s te m' *e m b rS c i 3 7 (1 8J I) @ IJ @

    G2JH 6i' , Q a ga i' Qa 9a caw a' S a ng' r ep a ra tio n o$ p o l% e th% le n e g l% c ol ( # .)

    a n" c e l l u l o s e a ce ta te (C &) b le n " m e m b ra n e s a n " th e i r g as p e rm e ab i:iti e s' 2

    &ppl o l% m S c i 5J (1 8 8 @) 1 7 5 51 7 @ @

    G28H . & rth a n aree s w a ra n' , S D e v i' * ? aaje n th ire n' # $$e ct o $ s ilic ap a rtic le s o n

    c ellu- lo se a c e ta te b le n " u ltra / ltra tion me m b ra n e s : a rt ' S ep u ri$ e c hn o l @J

    (20 0J)

    3 J7 I

    G30H # S a ljo u gh i' * S a"r a "eh' *o h a m m a "i' #$$e ct o $ p rep a r a t io n v a ria b le s on

    m o rp h o lo g% a n" p u re w a ter p e rm e a tio n A u> th ro u g h a s % m m e tric c e llu lo seac eta te m e mb ra n e s' * em b rS c i 3 2 @ (20 0 8 ) @ 2 I@ 37

    G31H S ,aw9' S; ,im' ;%bri" organ ic!ino rganic reverse osmosis (?=) membr a ne $or

    bacterici"al anti-$ouling 1 reparation an" characteriation o$ i=2 nanoparticle

    s e l$-a s s e m b le" a ro m a tic p o l% a m i" e t h in -/ lm- c o mp o s ite (1 0C) m e m b ran e'

    # nv iron S c i e c h no l 35 (20 0 1 ) 2 3 J J2 3 8 7

    G32H . u e g ue ' E * ra be t' # 0e rjan i' U S a n " c o n ta ct a n g le c h a ra c te ri a tio n o$

    su r$ ace mo" i/e" cellulose acetate membra n es b% mi>tur e s o$ *;S! D *S'

    Desalination

    3 1 3 (2 01 3) 2 0 J2 11

    G33H * & * a i" ' * e c ha n ism s o $ tra n sp o rt th ro u g h re v e rs e o s m o s is m e m b ra n e s' S epS c i

    e c h n o l ( 1 8 J7 ) 3 5 I3 I3

    G37H * M a $a r' * & li ' S * , h a n ' a m il ' * M E u tt' # $$e ct o$ a " " itiv es on the

    p rope rtie s an" per$orm a nce o$ cellulo s e acetate "erivat i ve memb r anes in the

    separat ion o$ is op rop a n o l!w a te r m i>tu re s'D e s a lin a tio n 2 J 5 (2 0 1 2) 3 5 83 @5

    G35H ; . E u r gh o $$ ' , 6 6 e e' u s c h ' Cha ra cteri ati on o$ tr a n sp o r t a cr o s s c e l lu l o s e

    ac e tat e m e mb r a ne s i n th epr es enc e o $ s tr o n g so lutemembran e inte ract i o ns '

    2 &pp l o l%m Sc i 2 5 (18 J 0 ) 3 2 33 7I

    G3@H ? * a la is a m %' ? *a he n" ra n' D * o h a n' * ? aje n " ra n' F * o h a n' C e llu lo s ea ce ta te a n " s u l $o n a te " p o l% s u l $o n e b l e n " u l tra / ltr a t i on m em bra ne s

    r ep ar a tio n a n" c h a ra c te ri a tio n' &pp l o l% m S c i J @ (2 0 02 ) 1 I 7 81 I@1

    G3IH E C h a9r a b a rt% ' &, . hos h an ' *, ur9 ai t ' #$ $e c t o $ m ole cul a r weig h t o $ # . on

    m embran e m or pholog% an " t ran spor t properties'2 *e m br Sci 30 8 (200I)

    2 082 21

    G3JH . & rth a n aree s w a ra n a'D * o h a n' * ?a ajen th iren' rep a ra tio n' c h a ra c te ri a tio n

    a n" per $o rm a nc e s t u"ie s o $ ult ra / l tr a ti on m e m b ra n e s w ith po l% m e r i c

    a ""itive' 2 * em b rS c i 3 5 0 (20 1 0 ) 1 3 01 3J

    G38H ; E a i' Z M h o u ' U a ng' 6 M h an g ' h e p e rm e ab ilit% a n " me c ha n ic al p rop e rti e s

    o$ c e llu lo se a c et a te me m b ran e s ble n" e " with pol% e th% lene gl % col @00 $or

    tr eat m ent o $ m u n ic ip a l s e w a g e' ro c e " ia # n v iro n S c i 1 @ (2 0 1 2 ) 3 7 @3 51

    G70H * * e n"e r gast ' # *F ;o e 9 ' & r ev i e w o $ wate r t r ea tmen t m e mbr a n e nano-

    technologies'#ne r g% # n v i ron S c i 7 (20 1 1 ) 1 8 7@1 8I1

    G71H Z i n ' # , im ' 2 Z a n g ' E D e n g ' 0a brication o $ a no v e l t h i n - /l m nanoco mposi t e

    (1 0Q) m em br an e c o n tai n ing *C* -7 1 s il ica n a n opar tic le s (Q s ) $o r wa te r

    p u ri/ca- tion'2 * embr Sc i 72 @ (2 0 12 ) 23J27@

    G72H 6 M o ua ' F i" a li s' D S te ele' & * ic h e lm o re' S 6 o w ' C F e rb e r9' S u r$a c e

    h %" ro-philic mo" i /cat i on o$ ?= memb r an e s b% pl a smapo l%meri a tion $or low

    organic $o u lin g ' * emb rS c i 3 @ 8 (20 1 1 ) 7 2 07 2J

    http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0075http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0080http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0085http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0090http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0095http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0100http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0105http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0250http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0015http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0110http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0115http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120http://refhub.elsevier.com/S0011-9164(14)00527-X/rf0120h