Research Article Pilot-Scale Removal of Trace Steroid...

Hindawi Publishing CorporationInternational Journal of Chemical EngineeringVolume 2013 Article ID 760915 10 pageshttpdxdoiorg1011552013760915

Research ArticlePilot-Scale Removal of Trace Steroid Hormones andPharmaceuticals and Personal Care Products from MunicipalWastewater Using a Heterogeneous Fentonrsquos Catalytic Process

George Tangyie Chi1 John Churchley2 and Katherine D Huddersman1

1 Faculty of Health and Life Sciences De Montfort University The Gateway Leicester LE1 9BH UK2 Severn Trent Water Ltd St Martins Road Finham Coventry CV1 2LZ UK

Correspondence should be addressed to George Tangyie Chi cgeorgedmuacuk

Received 24 August 2012 Revised 28 February 2013 Accepted 14 March 2013

Academic Editor Francesco Fatone

Copyright copy 2013 George Tangyie Chi et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

The pollution of water sources by endocrine disrupting compounds (EDCs) and pharmaceutical and personal care products(PPCPs) is a growing concern as conventional municipal wastewater treatment systems are not capable of completely removingthese contaminants A continuous stir tank reactor incorporating a modified polyacrylonitrile (PAN) catalyst and dosed withhydrogen peroxide in a heterogeneous Fentonrsquos process was used at pilot scale to remove these compounds from wastewaterthat has undergone previous treatment via a conventional wastewater treatment system The treatment system was effective atambient temperature and at the natural pH of the wastewater High levels of both natural and synthetic hormones (EDCs)and PPCPs were found in the effluent after biological treatment of the wastewater The treatment system incorporating themodified PAN catalystH

2O2decomposed gt90 of the EDCs and gt40 of PPCPs using 200mgLminus1 H

2O2 3 hr residence time

The estrogenic potency EE2-EQ was removed by 8277 9136 and 9613 from three different wastewater treatment plantsBOD was completely removed (below detection limits) 30ndash40 mineralisation was achieved and turbidity reduced by morethan 68There was a lt4 loss in iron content on the catalyst over the study period suggesting negligible leaching of the catalyst

1 Introduction

Endocrine disrupting compounds (EDCs)which include nat-ural sex hormones such as estronemdashE1 and 17 120573-estradiolmdashE2produced by humans and animals aswell as some syntheticestrogens such as 17 120572-ethinylestradiol (EE2) used for con-traception purposes are able to produce endocrine disrup-tion in living organisms at trace concentrations (nanogramper litre levels) [1 2] EDCs have been attributed as acause of reproductive disturbance in humans and wildlifesuch as feminisation of fish developmental abnormali-ties and demasculinisation of alligators [3] Pharmaceu-tical products such as antibiotics blood lipid regulatorsanalgesics nonsteroidal anti-inflammatory drugs antide-pressants antiepileptics impotence drugs tranquilizers andmany personal care products such as fragrances soaps

preservatives and disinfectants (generally called pharma-ceutical and personal care products (PPCPs)) have differentmodes of action toxicity and effects on nontarget organisms[4]

EDCs and PPCPs are released into the environmentby humans animals and industry mainly through sewagetreatment systems before reaching the receiving bodies (soilsurface water sediment and groundwater) [2] Municipalwastewater treatment plants are therefore major sinks ofseveral EDCs and PPCPs These micropollutants go throughmost conventional wastewater treatment plants (activatedsludge systems) partially removed or untreated Several stud-ies have shown that most conventional municipal treatmentplants are capable of removing only 27 of micropollutantsto below detection limits up to 64 of micropollutants areremoved by less than 50 and 9 are not removed at all

2 International Journal of Chemical Engineering

[1 4] ECDs and PPCPs have been detected in effluentsof sewage treatment plants (STPs) in different countries atconcentrations of up to 70 ngLminus1 for E1 64 ngLminus1 for E2 and42 ngLminus1 for EE2 and 63 120583gLminus1 for carbamazepine 27 120583gLminus1for triclosan and 53120583gLminus1 for aspirin [1 5 6] suggesting thatconventional treatmentmethods are not efficient in removinglow level EDCs and PPCPs

Human exposure to these chemicals in the environmentis of serious worry with unidentified long-term impacts Inthe past few decades research efforts to combat this problemhave grown immensely EDCs removal methods fall intothree categories physical removal (such as activated carbonsorptioncoagulation nanofiltration and reverse osmosis)biodegradation (membrane bioreactors activated sludge andweed beds) and advanced chemical oxidation processes(AOP) such as Fentonrsquos oxidation ozonationUVH

2O2 pho-

tocatalysis on TiO2 or a combination of these technologies

and chemical treatment method such as chlorine dioxideBiological methods such as membrane bioreactor and

activated sludge systems show inconsistency in removalefficiencies as it is highly dependent on the type of pollutanttemperature membrane matrix loads variability in loadsand quality of water to be treatedTheuse ofmembrane biore-actors (MBR) inwastewater treatment showedgt80 removalof the target EDCs and PPCPs (ZeeWeed-1 004 120583m hollowfiber ultrafiltration 0094m2 surface area 24 hrs hydraulicretention time corresponding to average flux of 43 Lmminus2 hminus1air flow rate of 150 Lminminus1) [7] Biological systems requirelong solid and hydraulic retention times and have a highhuman resource requirement for operation Adsorption ofcontaminant onto sludge is a significant removal mechanismhence requiring appropriate sludge treatment

Many researchers have demonstrated the effectiveness ofphysical methods such as activated carbon (granulated orpowder) and membranes towards the removal of a broadrange of EDCs and PPCPs from artificial and real wastewaterin the laboratory pilot- and full-scale plants A removal ofgt90 of several PPCPs and EDCs from a drinking watersource (spiked with 100 ngLminus1 each of targeted contaminants)by powdered (PAC) activated carbon at pilot scale withdynamic dosing of 35mgLminus1 PAC at 20ndash25∘C has beenreported [8] Similarly an evaluation of full-scale drinkingwater and wastewater treatment facilities utilizing granulatedactivated carbon technology showed that regularly regen-erated facilities were very effective in the removal of tracecontaminants whereas irregular regeneration was very poordue to fouling [6 8] Membrane filtration processes using acombination of reverse osmosis (RO) and nanofiltration (NF)have been reported with excellent removal (gt95) of targetcompounds whereas microfiltration and ultrafiltration arenot very effective [6 9] Notwithstanding this high removalefficiency physical methods only transfer the contaminationfrom one medium to another Additionally membrane andsorption technologies require frequent costly regenerationandor backwashing due to organic fouling and biofoulingas several compounds are often detectable in membranepermeates and carbon effluent hence limiting the adoptionof these technologies in the industry [6 8 9] Additionally

physical and biological processes generally generate sludgeor reject which is more contaminated than the originalwastewater and so require further treatment

AOPs involving the generation of radicals have gainedsignificant interest because of their excellent removal capa-bilities and their ability to decompose the micropollutantsrather than simply transferring from one medium to another[4 10ndash12] While ozonation [11 13 14] Fentonrsquos photo-Fentonrsquos [14 15] and solar photocatalysis [16] have shownexcellent performances operational costs of ozonation sys-tems remain high and the generation of sludge in homo-geneous Fentonrsquos system due to the formation of insolubleiron species coupled with restricted operational pH range(2ndash4) remains a problem Heterogeneous Fentonrsquos systemstherefore exhibit greater potential with regard to costs and nosludge generation However there is limited information onheterogeneous Fentonrsquos processes in the literature

The heterogeneous polyacrylonitrile (PAN) catalystH2O2has shown potential at lab scale in the treatment of syn-

thetic organic contaminants [17ndash19]This study aims to exam-ine the effectives of the heterogeneous PAN catalystH

2O2

at a pilot scale towards the removal of selected EDCs andPPCPs from pretreated (activated sludge treated) municipalwastewater The pretreated wastewater was obtained fromthree of Severn Trent Waterrsquos sewage works in the MidlandsUK Lump parameters such as chemical oxygen demand(COD) and total organic carbon (TOC) were determinedThe effectiveness of the system towards the removal of naturalhormones estrone (E1) and 17 120573-estradiol (E2) synthetichormone 17 120572-ethinylestradiol (EE2) and PPCPs such ascarbamazepine triclosan and aspirin detected in effluentsdischarges from the sewage treatment plants was investi-gated In this work the use of the heterogeneous PAN catalystin a continuous flow process and at pilot scale is beingreported for the first time Environmental legislation on thedischarge of emerging contaminants and micropollutants islikely to become tighter in the near future rendering thesearch for new effective treatment technologies relevant

2 Materials and Methods

21 Wastewater Source Severn Trent Water (STW) is amunicipal water companymdashserving over 8million customersacross the heart of the UK stretching from the Bristol Chan-nel to the Humber and frommid-Wales to the East MidlandsThe company treats around 27 billion litres of wastewaterand sewage each day from communities and businessesacross the region and the treated water is discharged intoneighbouring streams and rivers This is performed in about1018 sewage treatment works 20 surface water treatmentworks and about 43 sludge treatment facilities across theregion The pilot system was tested on sewage from threedifferent STW treatment works in the Midlands namely SiteA Site B and Site C The true names of the different siteshave not been included in this paper for security reasonsand data protection Wastewater used in this study had beenthrough physical treatment (screens and grit removal andprimary sedimentation tanks) activated sludge tanks andsecondary clarifiers (see Figure 1) The wastewater at this

International Journal of Chemical Engineering 3

Influent Preliminarytreatment

Primary Biologicaltreatment

Sandfiltration

Effluentsedimentation

Pilot plant location

Rotating catalyticcontactor (RCC)

Screeningsand grit

Waste disposal Sludge treatment

Secondarysludge

Primarysludge

Figure 1 Conventional sewage treatment plant showing the location of the pilot plant for this study

stage is normally treated on sand filters and subsequentlydischarged into receiving waters The sand filter does notremove these recalcitrant EDCs and PPCPs hence usingpresand filter effluent in this work was for convenience only

22 Physicochemical Properties of EDCs and PPCPs StudiedTables 1(a) and 1(b) show the physical and chemical proper-ties of EDCs and PPCPs studied Amongst the compoundsstudied aspirin is the most soluble (lowest log119870ow) andtriclosan is the least soluble suggesting that triclosan isthe most likely to adsorb onto sludge during biological orphysical treatment

23 Reagents All EDC PPCPs and metal standards wereof analytical grade (gt95 purity) and were purchased fromSigma-Aldrich (Gillingham Dorset UK) Solvents used forextraction and as HPLC mobile phase (dichloromethanediethyl ether methanol hexane and acetone) were allHPLC grade and were purchased from Rathburn Chem-icals (Walkerburn Scotland UK) and Fisher Scientific(Loughborough UK) Solid phase extraction cartridgesand hydroxylated polystyrene divinylbenzene (ENV+) wereobtained from International Sorbent Technologies (HengoedMid Glamorgan UK) and Oasis HLB was obtained fromWaters Ltd (Elstree Hertfordshire UK) Ultrapure water wasobtained with a Milli-Q water purification system

24 Sampling Inlet and outlet samples from the pilot plantwere collected as a single grab sample and transferred tosampling containers containing preservative as follows 25 Lamber glass bottles containing copper nitrate (05 g) andhydrochloric acid (6mL) (for measuring EDCs and PPCPs)25 L amber glass bottle containing hydrochloric acid (6mL)(for metals) and 10 L PET bottle for standard sanitaryanalysis (no preservative added) Samples were transportedto the laboratory in ice-packed coolers (4ndash6∘C) The sampleswere stored in a refrigerator below 6∘C prior to extractionof analytes performed within 48 hours of sampling Influentand effluent samples were filtered through 045 120583mmethanolwashed glass fiber filters (Fisher Scientific Milford MA)

Processed samples were then stored at minus5∘C Samples werecollected twice a day

25 Modified PAN Catalyst Production Wet spun PAN yarnwas supplied by PERA Innovation Melton Mowbray UKAn open mesh structure comprising PAN yarn enhancesthe hydrodynamic properties and physical strength of thefinished product The PAN mesh was chemically modifiedby reacting 279 g of PAN mesh in 1 L solution of 496 g Lminus1hydroxylamine sulphate (99) and 2317 g Lminus1 dihydrazinesulphate (98) at pH 95 100 plusmn 2∘C under reflux for 2 h andwith constant stirring It was thoroughly washed to removeresidual chemicals The modified PAN was impregnated atroom temperature using a solution of 75 g Lminus1 FeCl

3sdot6H2O

(99) and 2249wv Ca(NO3)2sdot4H2O for 2 h with con-

tinuous stirring The catalyst was then washed thoroughlyand spin dried at room temperature The catalyst productionprocess is described in detail elsewhere [18]

26 Analytics Samples were analysed for EDCs (E1 E2 andEE2) using the LC-MSMS method as described elsewhere[20 21] Briefly the samples were first filtered to removeparticulate matter (Whatman GFDGFF of 1120583m nominalpore size) After addition of a mixed deuterated internalstandard (2 4 16 16-d

4-estrone 2 4 16 16-d

4-17 120572-estradiol

and 2 4 16 16-d4-17 120573-ethynyl estradiol) 500mL of the

sample was extracted onto a conditioned styrene divinyl-benzene cartridge (ENV+) The cartridge was dried undervacuum and then eluted with dichloromethane which wasthen concentrated to 100120583L prior to an initial clean-up usinggel permeation chromatography (GPC)TheGPC extract wasthen concentrated to 200120583L using a TurboVap concentratorand nitrogen blowdown apparatus The extract was furthercleaned using an Isolute aminopropyl SPE cartridge whichwas loaded and was washed with ethyl acetate in hexaneprior to elution with ethyl acetate in acetone The extractwas then reduced to incipient dryness using nitrogen andthe residue was taken up in methanol and quantified byliquid chromatography with tandemmass spectrometry (LC-MSMS)


Table 1 EDCs and PPCPs investigated in the effluents

(a)

Chemical name Classification Molecular weight (gmolminus1) Water solubility (mg Lminus1 at 25∘C) log 119870owEstrone (E1) Steroid 2704 30 34317 120573-Estradiol (E2) Steroid 2724 25 39417 120572-Ethynylestradiol (EE2) Steroid 2964 48 415Carbamazepine Analgesic 2363 177 245Aspirin NSAID 1802 5295 113Triclosan Antiseptic 2895 46 476

(b)

Names Structure Uses and effects

Estrone (E1)

OH3C

OH

Estrogenic hormone secreted by the ovary

17 120573-Estradiol (E2)

HO

OHCH3 Sex hormonemdashOestrogen Estradiol has a critical impact on

reproductive and sexual functioning as well as organs includingbone structure

17 120572-Ethinylestradiol (EE2)

H

H

H

H

HO

CHHO

Synthetic form of Estradiol used for contraception

Carbamazepine

O

H2N N Anticonvulsant and mood stabilizing drug used primarily inthe treatment of epilepsy and bipolar disorder

Aspirin

H3C

HO

O

O

O

Used to treat fever pain rheumatic fever and inflammatorydiseases such as rheumatoid pericarditis and arthritis

TriclosanO

HO

Cl

Cl Cl

Triclosan is found in soaps (015ndash030) deodorantstoothpastes mouth washes and cleaning supplies acting asantifungal and antibacterial It is an endocrine disruptor It cancombine with chlorine in water to form chloroform which is acarcinogen

LC-MSMS analysis was performed using a HewlettPackard 1100 LC Optimised HPLC conditions were Supel-cosil LC-18 (46mm times 250mm 5 120583m) column supplied bySupelco mobile phase 43 acetonitrile 57 water flow

rate 1mLminminus1 and column temperature 25∘C An AppliedBiosystems API5000 mass spectrometer using negative ionelectrospray in multiple reaction monitoring (MRM) modewas used Positive identification of EDCs was carried out by


comparison of retention time and ion abundance ratios of thequantitation and confirmation mass transitions to those of areference standard compound

The PPCPs were analysed by GC-MS without derivati-sation as it is the best technique for such compounds [22]In summary 500mL of the acidified and filtered sampleswas percolated through a Waters Oasis HLB 12 cm3 500mgcartridge preconditioned with 6mL dichloromethane 6mLacetonitrile and 6mL of milliQ water at 5mLminminus1The cartridge was rinsed with 2mL milliQ water anddried by vacuum for 10min The elution was carried outwith 5mL of acetonitrile-dichloromethane (1 1) and 32mLdichloromethane The eluate was transferred to vials andexcess solvent evaporated to dryness as described previouslyThe extract was subsequently taken up into isooctane andinjected in the GC-MS system

The GC-MS analyses were performed using a FisonsMD 800 mass spectrometer operated in EI mode at 70 eVA sample volume of 1 120583L was injected in splitless mode atan inlet temperature of 230∘C The carrier gas was heliumand maintained at a constant flow rate of 09mLminminus1 Thegas chromatograph was equipped with a capillary columnDB-5MS (30m long times 025mm ID) with 025120583m filmthickness (from Agilent Technologies) The temperature wasprogrammed from 90∘C for 1min ramped from 90∘C to120∘C at 10∘Cminminus1 and from 120∘C to 200∘C at 5∘Cminminus1and then to 280∘C at 10∘Cminminus1 and finally held for 5minThe MS transfer line temperature was maintained at 280∘Cwhereas the ion source temperature was 180∘C Quantitativeanalysis was carried out using selected ion monitoring (SIM)mode For each compound the most abundant ions wereselected from its spectrum The chosen ions for SIM were120 43 138 92 and 180 for aspirin 193 236 and 192 forcarbamazepine and 288 218 and 146 for triclosan

The TOC content of the oxidised solution was analysedusing theThermalox TCTIC analyserThe TOC content wasdetermined indirectly by calculating the difference betweentotal carbon (TC) and total inorganic carbon (TIC) Eachsample was analysed in triplicates Metals were analysedby ICP-AES after filtration and acidification of the sampleBOD phosphates and turbidity were analysed followingwell-documented standard methods [23] Site measurements(temperature and pH) were performed using pH and temper-ature probes linked to data loggers

27 Experimental Conditions The continuous stir tank reac-tor contained the modified PAN catalyst corresponding to131 moles of iron catalyst The treatment of effluent wasperformed at ambient temperatures and at natural pH Theresidence time of treatment process was 3 hours with acorresponding flow rate of 106 Lhrminus1The total volume of thereactor was 3134 dmminus3

Hydrogen peroxide was continuously dosed at the inletand halfway along the length of the reactor with the help ofperistaltic pumps The amount of hydrogen peroxide dosingwas calculated based on the theoretical amount of oxygenrequired for the complete mineralisation of the organicpollutants (in terms of COD) by considering the oxygen

requirement (COD) of the wastewater according to thefollowing equation

Required H2O2(mgLminus1)

= COD (mgLminus1) lowast 2 (molar mass of H2O2

molar mass of O2

)

(1)

From (1) 1 g of COD = 1 g O2= 003125mol O

2

Hence required amount of H2O2(mgLminus1) = COD (mg

L) lowast 2125The corresponding required concentration of H

2O2was

calculated to be 1995mgLminus1 for a COD of 939mgLminus1 Themass flow of hydrogen peroxide 119865 (mgminminus1) required to bemixed with the effluent flowing through the prototype wascalculated using

119865 = (

119881 lowast [H2O2]

120591

) (2)

where119881mdashmain trough volume (L) [H2O2]mdashrequired H

2O2

concentration (mgLminus1) and 120591 residence time (min)The mass flow rate of H

2O2was calculated according to

(2) to be 347mgminminus1 dosed using peristaltic pumps

3 Results

31 Quality of Wastewater to Be Treated The characteristicsof the wastewater used for the pilot treatment are shownin Table 2 The wastewater from Site A used as influentfor this field trial (designated partially treated wastewater)had the smallest amounts of total suspended solids (about6mgLminus1) and hence turbidity (065 Formazin NephelometricUnit FTU) whereas wastewater from Site C had the largestamount of suspended solids (about 11mgLminus1) Meanwhilethe minimum requirements for discharge of total suspendedsolids from urban wastewater treatment plants in the Euro-pean Union are 35mgLminus1 TSS [24]

The concentration of phosphates ranged from 02mgLminus1in Site A to 65mgLminus1 in Site C Site C was thought to bevery high in phosphates because of the underlying groundproperties of the area The levels of metals found in theeffluent from all the three sites were below UK dischargestandards The UK standards for the concentration of leadaluminium and copper in drinking water are 25 120583gLminus1200120583gLminus1 and 2mgLminus1 respectively [20] EDCs and PPCPsin the biologically treated wastewater ranged from belowdetection limits to 46 ngLminus1 confirming that conventionalsewage treatment plants are not capable of completely remov-ing these compounds The potency of steroid estrogenswas expressed in terms of estradiol equivalents (E2-EQ)according to the following equation [25]

Estradiol equivalent (E2-EQ)

= 033 lowast E1 + E2 + 10 lowast EE2 (ngLminus1) (3)

Mean values of E1 E2 and EE2 were used to cal-culate the E2-EQ The E2-EQ for Sites A B and C


Table 2 Characteristics of biologically treated wastewater used in the pilot tertiary treatment process

Units LOQ Site A concentration Site B concentration Site C concentrationRange Mean Range Mean Range Mean

BOD (ATU) [mg Lminus1] 1 1ndash3 25 1ndash5 35 6ndash13 83TOC [mg Lminus1] 01 60ndash75 624 79ndash92 810 107ndash148 1108TSS [mg Lminus1] 01 40ndash81 85 64ndash129 95 100ndash120 107Turbidity [mg Lminus1] 005 06ndash069 066 40ndash46 47 34ndash88 78PO4

3minus [mg Lminus1] 0004 012ndash38 026 049ndash099 069 330ndash664 538Total

Al [120583g Lminus1] 11 24ndash38 315 25ndash39 29 35ndash124 897Pb [120583g Lminus1] 05 06ndash25 225 06ndash16 095 13ndash18 14Cu [120583g Lminus1] 27 27ndash39 34 lt27 27 47ndash8 69Fe [120583g Lminus1] 15 538ndash618 5745 163ndash219 209 67ndash91 84Mn [120583g Lminus1] 15 lt15 lt15 lt15 lt15 16ndash21 20

Estrone (E1) [ng Lminus1] 005 167ndash287 212 005ndash131 07 302ndash463 35517 120573-Estradiol (E2) [ng Lminus1] 005 033ndash042 039 lt005 lt005 422ndash652 51217 120572-Ethinylestradiol (EE2) [ng Lminus1] 005 023ndash026 0255 051ndash068 0575 153ndash172 1565Carbamazepine [ng Lminus1] 10 668ndash877 7575 553ndash842 589 945ndash1160 10025Aspirin [ng Lminus1] 10 10ndash23 17 10ndash29 16 lt10 lt10Triclosan [ng Lminus1] 10 149ndash152 151 55ndash89 735 383ndash473 438

were 365 ngLminus1 598 ngLminus1 and 3260 ngLminus1 According toWilliams et al [26] treated water discharged from the con-ventional STP at Sites A and B could be classed as low risk(1 lt E2-EQ le 10 ngLminus1) whereas that from Site C could beclassed as high risk (E2-EQ gt 10 ngLminus1)

32 pH and Temperature Change during the Treatment ThepH of the effluent was monitored during the treatmentprocessThe initial pH of Site A Site B and Site C wastewaterwere about 653 plusmn 3 699 plusmn 2 and 799 plusmn 2 respectivelyAfter treatment using the modified PAN catalyst systemthere was no significant change in pH The performance ofthe heterogeneous Fentonrsquos process at the natural pH of thewastewater is a major advantage of themodified PAN catalystover traditional homogeneous Fentonrsquos which is limited to pH2ndash4 [27] The effectiveness of the system at the natural pH ofthe effluent could be attributed to the fact that the ligandsholding the metals prevent the iron from precipitating asit is the case in homogeneous Fentonrsquos at pH gt4 A similarobservation has been reported where Fentonrsquos oxidation oforganic pollutants was successfully performed at near neutralpH in the presence of dissolved organic matter in the formof humic as ligands for the homogeneous iron Similarlyethylenediamine-N-N1015840-disuccinic acid (EDD) complexes inanother study were used for stabilisation and solubilisationof iron at natural pH [10 27] The pilot-scale modified PANcatalyst treatment was performed at ambient temperaturevarying between 12∘C and 20∘C

33 Removal of EDCs and PPCPs As shown in Table 2the concentration of estrogens in the effluents ranged from

lt005 to 463 ngLminus1 with highest concentrations at Site CEstrone was the most abundant estrogen in the effluentfrom all three sites The presence of steroid hormones inthe conventionally treated wastewater is consistent withseveral studies which have shown that sewage treatmentplants are a significant point source of endocrine disruptingcompounds particularly for surface water and undergroundwater [14 16] Natural estrogens for example estrone (E1)17 120573-estradiol (E2) and estriol (E3) and synthetic estrogenssuch as 17 120572-ethinylestradiol (EE2) and nonylphenols havebeen found to be the major contributors to the estrogenicactivity observed in sewage effluents in the United Kingdom[28] Concentrations as low as 01 ngLminus1 of an estrogen cancause significant estrogenic effects [29]

More than 80 of the estrogens were decomposed by themodified PAN catalystH

2O2treatment system Removal was

generally higher for Site C even though the concentrationsof the EDCs in Site C were significantly higher than those inSites A and B (Figure 2)The estrogenic potency EE2-EQ wasremoved by 8277 9136 and 9613 from Sites A B andC respectively The treated effluent from Sites A and B couldbe classed as no risk as E2-EQ was lt1 ngLminus1 whereas E2-EQafter treatment in Site C was 126 ngLminus1 and could be classedas low risk as it is less than 10 ngLminus1 [26]

The concentration of triclosan in the untreated effluentsranged from 55 to 493 ngLminus1 More than 84 of triclosanwas constantly removed at each of the three treatment sitesHigh levels of carbamazepine were found in the effluent fromall three sites ranging from 553 ngLminus1 to 1060 ngLminus1 Aftertreatment 8448 4601 and 4788 of carbamazepinewere removed from the wastewater from Sites A B and C


12000

10000

8000

6000

4000

2000

000

Site ASite BSite C

Carb

amaz

epin

e

Asp

irin

Tric

losa

nE1 E2 EE2

Rem

oval

()

Figure 2 Removal of EDCs and PPCPs (E1mdashestrone E2mdash17 120573-estradiol and EE2mdash17 120572-ethinyl estradiol)

respectively (Figure 2) The removal of carbamazepine waslow for Sites B and C and the reason for the deviation inperformance from Site A is not well understood Meanwhilethe removal of this compound could be enhanced by increas-ing the initial concentration of hydrogen peroxide andorextending the residence time

In comparison to other AOPs a 658 825 and 91 plusmn8 removal of estrone carbamazepine and triclosan frominitial concentrations of 233 ngLminus1 36 ngLminus1 and 118 ngLminus1respectively has been reported in the pilot-scale ozonationtreatment of municipal wastewater that has been pretreatedbiologically and sand filtered using 3mgLminus1 O

3with a

27min residence time [14] Poor removal times (85 after475mins) of micropollutants including carbamazepine (50ndash114 ngLminus1 initial concentration) have been reported in the ter-tiary treatment of municipal wastewater using heterogeneoussolar photocatalysis at pilot plant scale (treatment conditions20mgLminus1 TiO

2 pH 6 35 L batch treatment of biologically

treated municipal wastewater followed by carbonate elimina-tion) [16] However the same group reported agt90 removalof themicropollutantswithin 20minutes using homogeneoussolar photo-Fentonrsquos (60mg Lminus1 H

2O2 5mgLminus1 Fe(II) pH

28) and within 60mins using ozone (9mgLminus1 O3 pH 8)

This technology is therefore very competitive with otheradvanced oxidation technologies in terms of reaction timesand performance with the added advantage of natural pHoperating conditions and the simplicity of a heterogeneousmode In comparison acidic conditions and continuous irondosage require pH readjustment and metal removal aftertreatment using homogeneous Fentonrsquos and photo-Fentonrsquossystems

The removal of the EDCs is through the decompositionof the compounds by hydroxyl radicals and other oxidativespecies generated from the reaction between peroxide in

solution and iron on the catalyst according to the Fenton-likeprocess as illustrated in (4)ndash(8) and Scheme 1 [11 12]

L-Fe2+ +H2O2997888rarr L-Fe3+ +HO∙ +HOminus (4)

L-Fe3+ +H2O2997888rarr L-Fe2+ +HO∙

2+H+ (5)

The free or bound radicals produced then react with theorganic pollutant (substrate) as shown in (6)ndash(8)

HO∙ + Substrate 997888rarr R∙ Fe3+997888997888997888rarr Product + Fe2+ (6)

HO∙ + Substrate 997888rarr R∙ 997888rarr Dimerisation (7)


The very good removal of the steroid hormones (E1 E2and EE2) could be attributed to the attack of the phenolicmoieties present in these compounds Phenolic compoundsgenerally have high removal efficiencies by hydroxyl radicalsas a result of the activating ability of the benzene ring by thehydroxyl group [11 12] The removal of carbamazepine wasnot very good and could be attributed to the deactivation ofthe azepine ring by the electron withdrawing amide groupThis poor removal is consistent with a removal of 37 frompostbiologically treated municipal wastewater containing263 ngLminus1 carbamazepine by homogeneous Fentonrsquos (5mgLminus1Fe(II) and 50mgLminus1 H

2O2 30min treatment time at 17∘C)

[10] The effective removal of triclosan is consistent with thepresence of the phenolic moiety which is dominant over theweakly deactivating chlorine substitutes The oxidation ofaspirin was not consistent probably due to the very low levelsthat are close to the limit of quantification

Negligible hydrogen peroxide was measured in the efflu-ent that had been treated suggesting that all the peroxidewas used up hence negligible discharge of H

2O2to receiving

waters Additionally only small amounts of iron (0067ndash067mgLminus1) were present in the feed At such small concen-trations neutral pH low temperature and 200mgLminus1 H

2O2

the contribution of homogeneous Fentonrsquos reactions towardsthe degradation of the organic compounds is insignificant[30]

34 Removal of BOD TOC TSS and Turbidity The sanitary(BOD TOC TSS and turbidity) and inorganic characteris-tics of the samples before and after treatment were analysedThe Biological Oxygen Demand (BOD) was reduced toless than 1mgLminus1 for all the effluents treated using theRCCmodified PAN catalyst treatment systemThe reductionin BOD could be attributed to the oxidation of organicpollutants into forms that are no longer able to be oxidisedby the bacteria used in BOD measurement According toBOD classification for water quality Site C was the worst ofthe three sites in terms of pollution by organics (6ndash13mgLminus1BODmdashPoor somewhat polluted) However the require-ments for BOD discharge from urban wastewater treatmentplants in the European Union are 25mgLminus1 oxygen [24]


(free radical)

minusL

(ferryl ion)

L H+Excess H2O2

L119909minus1FeOFe5+L119909minus1

L119909minus1FeIV=O + H2O

L119909FeIII + H2O

L119909FeII + H2O2 [L119909FeII ndashOndashOH + H+]

L119909minus1FeIII ndashO---OHL119909minus1FeIII ndashOH+∙OH(bound ∙OH)

Scheme 1 Possible reactions of H2O2with ligated ferrous iron

Rem

oval

()

1200

1000

800

600

400

200

00

Site ASite BSite C

BOD TOC TSS Turbidity Phosphate

Figure 3 Sanitary and inorganic parameters monitored during thepilot-scale tertiary treatment of municipal wastewater using therotating catalytic contactor

Moreover there was about 30ndash40 reduction in thetotal organic carbon (TOC) content of wastewaters treated(Figure 3) This suggests that 30ndash40 of organic com-pounds present in the wastewater were mineralised to pro-duce CO

2and water Although TOC removal is somewhat

low the oxidation of these organic pollutants generally resultsin the formation of low molecular weight organic acids thatare readily biodegradable [18] but which results in no changein TOC It is has been widely reported that the oxidation ofPPCP and steroid hormones by hydroxyl radicals results inloss of estrogenicity [14] TOC removal can be enhanced byincreasing hydrogen peroxide dosing

In comparison TOC removal of 189 and 539 hasbeen reported for homogeneous dark Fentonrsquos and photo-Fentonrsquos using zero valent iron (Fe0) (conditions 99mgLminus1H2O2 5mgLminus1 Fe0 H

2O2 COD2 1 2730mgLminus1 initial TOC

in real wastewater pH 3 120min reaction time bench scalebatch mode) [31] Hence the heterogeneous modified PANsystem is better in that it uses less H

2O2with H

2O2 COD

of 1 1 neutral pH though with a residence time of 180minH2O2is the single most expensive cost item in Fentonrsquos

processes hence lower peroxide usage renders the technologymore competitive

Moreover a 50 reduction in total suspended solidswas achieved This could be attributed to the breakdown ofhumic substances and the filtration properties of themodifiedPAN catalyst The net-like structure (mesh) of the modifiedPAN catalyst makes it very suitable for filtering out Coarseparticles This was evident as the catalyst upstream of thereactor looked physically fouled by solids in comparison tothose downstream

After treatment the turbidity reduced by 68 up to 91for the three sites Turbidity values of lt2 FTU were achievedthereby rendering the water more suitable for discharge intostreams The removal mechanism for turbidity is thought tobe a consequence of suspended solids removal

Phosphates were found in significant amounts especiallyat Site CThe consequences of eutrophication resulting fromhigh nutrient levels in waters (lakes streams and rivers)are of great concern Phosphate levels were reduced by morethan 90 (Figure 3)The ability of the modified PAN catalystto remove phosphate serves as an added advantage thoughits effect on the performance of the catalyst is still underinvestigation

35 Catalyst Leaching The amount of iron on modified PANcatalyst used in this field trial was determined from threedifferent positions on pieces of mesh at increasing distancesfrom the inlet Iron content at each position was measured intriplicates From Figure 4 there was no significant change inthe iron content on the modified PAN catalyst after the studyperiod suggesting that there is negligible leaching of catalystHowever there was a slight decrease in iron content towardsthe outlet of the treatment unitThere was high uniformity iniron content on the catalytic mesh

After 2 months of continuous use the catalytic mediawere chemically regenerated in situ by backwashing with asolution of 1 gLminus1 peroxide at pH 35 The washing processeffectively removed the suspended solids from the catalyticmedia and also desorbed some of the weakly adsorbedmetals This was evident by the presence of metals in thewash solution However the amounts of metals in the washsolution were very small and so nutrient recovery was notconsidered in this work

International Journal of Chemical Engineering 9gminus

1 )

0 13 23 30 38 45Unused

03

025

015

01

005

0

02

Resid

ual i

ron

cont

ent (

mm

ol

Distance from inlet (cm)

Figure 4 Iron content on fresh and used modified PAN catalyst

4 Conclusion

The modified PAN catalyst system was effective in thetreatment of the wastewater owing to its ease of use potentialfor automation and rigidity of the catalytic mesh Thetreatment system was effective at ambient temperature andat the natural pH of the effluent hence no pH adjustmentwas required High levels of both natural and synthetichormones (EDCs) and PPCPs were found in the effluentafter biological treatment (but before sand filtration) at themunicipal wastewater sites of STW The treatment systemincorporating the modified PAN catalystH

2O2decomposed

gt90 of the EDCs and gt40 of PPCPs using 200mgLminus1H2O2 3 hr residence time The estrogenic potency EE2-EQ

was removed by 8277 9136 and 9613 from Sites AB and C respectively There was a lt4 loss in iron contentfrom the catalyst over the study period suggesting negligibleleaching of the catalyst BODwas completely removed (belowdetection limits) 30ndash40mineralisation was achieved andturbidity reduced by more than 68 The modified PANcatalyst system shows great potential in the removal of lowlevels of PPCPs and EDCs when compared to homogeneousFentonrsquos photo-Fentonrsquos electro-Fentonrsquos and photocatalysison TiO

2 owing to the low energy requirement ease of oper-

ation ambient temperature and natural pH performanceHowever the cost and life time of the catalyst will need tobe assessed so as to be compared with other AOPsThe effectof operational parameters on the performance of the systemis a subject for further work

Acknowledgments

The authors are grateful to the DTI for funding this study andSevern Trent Water for their cooperation

References

[1] S Combalbert and G Hernandez-Raquet ldquoOccurrence fateand biodegradation of estrogens in sewage and manurerdquo

Applied Microbiology and Biotechnology vol 86 no 6 pp 1671ndash1692 2010

[2] R J Williams A C Johnson J J L Smith and R KandaldquoSteroid estrogens profiles along river stretches arising fromsewage treatment works dischargesrdquo Environmental Science andTechnology vol 37 no 9 pp 1744ndash1750 2003

[3] C G Campbell S E Borglin F B Green A Grayson EWozeiand W T Stringfellow ldquoBiologically directed environmentalmonitoring fate and transport of estrogenic endocrine disrupt-ing compounds in water a reviewrdquo Chemosphere vol 65 no 8pp 1265ndash1280 2006

[4] N Bolong A F Ismail M R Salim and T Matsuura ldquoAreview of the effects of emerging contaminants in wastewaterand options for their removalrdquo Desalination vol 238 no 1ndash3pp 229ndash246 2009

[5] T A Ternes M Stumpf J Mueller K Haberer R D Wilkenand M Servos ldquoBehavior and occurrence of estrogens inmunicipal sewage treatment plantsmdashI Investigations in Ger-many Canada and Brazilrdquo Science of the Total Environment vol225 no 1-2 pp 81ndash90 1999

[6] S D Kim J Cho I S Kim B J Vanderford and S A SnyderldquoOccurrence and removal of pharmaceuticals and endocrinedisruptors in SouthKorean surface drinking andwastewatersrdquoWater Research vol 41 no 5 pp 1013ndash1021 2007

[7] F I Hai K Tessmer L NNguyen J KangW E Price and L DNghiem ldquoRemoval of micropollutants bymembrane bioreactorunder temperature variationrdquo Journal of Membrane Science vol383 no 1-2 pp 144ndash151 2011

[8] S A Snyder S Adham A M Redding et al ldquoRole ofmembranes and activated carbon in the removal of endocrinedisruptors and pharmaceuticalsrdquoDesalination vol 202 no 1ndash3pp 156ndash181 2007

[9] M Gomez G Garralon F Plaza R Vılchez E Hontoria andM A Gomez ldquoRejection of endocrine disrupting compounds(bisphenol A bisphenol F and triethyleneglycol dimethacry-late) by membrane technologiesrdquoDesalination vol 212 no 1ndash3pp 79ndash91 2007

[10] N de la Cruz J Gimenez S Esplugas D Grandjean L Fde Alencastro and C Pulgarın ldquoDegradation of 32 emergentcontaminants by UV and neutral photo-fenton in domesticwastewater effluent previously treated by activated sludgerdquoWater Research vol 46 no 6 pp 1947ndash1957 2012

[11] M M Huber S Canonica G Y Park and U von GuntenldquoOxidation of pharmaceuticals during ozonation and advancedoxidation processesrdquo Environmental Science and Technologyvol 37 no 5 pp 1016ndash1024 2003

[12] U von Gunten ldquoOzonation of drinking water part I Oxidationkinetics and product formationrdquo Water Research vol 37 no 7pp 1443ndash1467 2003

[13] J NakrstM Bistan T Tisler J Zagorc-Koncan J Derco andAZ Gotvajn ldquoComparison of Fentonrsquos oxidation and ozonationfor removal of estrogensrdquoWater Science and Technology vol 63no 10 pp 2131ndash2137 2011

[14] N Nakada H Shinohara AMurata et al ldquoRemoval of selectedpharmaceuticals and personal care products (PPCPs) andendocrine-disrupting chemicals (EDCs) during sand filtrationand ozonation at a municipal sewage treatment plantrdquo WaterResearch vol 41 no 19 pp 4373ndash4382 2007

[15] Z Frontistis N P Xekoukoulotakis E Hapeshi D VenieriD Fatta-Kassinos and D Mantzavinos ldquoFast degradation


of estrogen hormones in environmental matrices by photo-Fenton oxidation under simulated solar radiationrdquo ChemicalEngineering Journal vol 178 pp 175ndash182 2011

[16] L Prieto-Rodrıguez I Oller N Klamerth A Aguera E MRodrıguez and S Malato ldquoApplication of solar AOPs andozonation for elimination of micropollutants in municipalwastewater treatment plant effluentsrdquo Water Research vol 47no 4 pp 1521ndash1528 2013

[17] G T Chi Z K Nagy and K D Huddersman ldquoKineticmodelling of the Fenton-like oxidation of maleic acid usinga heterogeneous modified polyacrylonitrile (PAN) catalystrdquoProgress in Reaction Kinetics and Mechanism vol 36 no 3 pp189ndash214 2011

[18] G T Chi and K D Huddersman ldquoMaleic acid oxidationusing a heterogeneousmodified polyacrylonitrile (PAN)fibrouscatalystrdquo Journal of AdvancedOxidationTechnologies vol 14 no2 pp 235ndash243 2011

[19] Z Yang V V Ishtchenko and K D Huddersman ldquoNovelfibrous catalyst in advanced oxidation of photographic process-ing effluentsrdquo Journal of Environmental Science and Health Avol 41 no 2 pp 129ndash141 2006

[20] R Kanda and J Churchley ldquoRemoval of endocrine disruptingcompounds during conventional wastewater treatmentrdquo Envi-ronmental Technology vol 29 no 3 pp 315ndash323 2008

[21] DWestwoodTheDetermination of SteroidOestrogens inWatersUsing Chromatography and Mass Spectrometry Methods for theExamination of Waters and Associated Materials vol 58 2005

[22] T A Ternes ldquoAnalytical methods for the determination ofpharmaceuticals in aqueous environmental samplesrdquo Trends inAnalytical Chemistry vol 20 no 8 pp 419ndash434 2001

[23] E W Rice R B Baird A D Eaton and L S Clesceri StandardMethods for the Examination of Water and Wastewater 2005

[24] T Zabel I Milne and G Mckay ldquoApproaches adopted by theEuropean Union and selected Member States for the control ofurban pollutionrdquo Urban Water vol 3 no 1-2 pp 25ndash32 2001

[25] W F Young P Whitehouse I Johnson and N Sorokin ldquoPro-posed predicted-no-effect-concentrations (PNECs) for naturaland synthetic steroid oestrogens in surface watersrdquo Environ-ment Agency RampD Dissemination Centre RampD TechnicalReport P2-T041 2004

[26] R JWilliams VD J Keller A C Johnson et al ldquoA national riskassessment for intersex in fish arising from steroid estrogensrdquoEnvironmental Toxicology and Chemistry vol 28 no 1 pp 220ndash230 2009

[27] N Klamerth S Malato A Aguera and A Fernandez-AlbaldquoPhoto-Fenton and modified photo-Fenton at neutral pH forthe treatment of emerging contaminants in wastewater treat-ment plant effluents a comparisonrdquoWater Research vol 47 no2 pp 833ndash840 2013

[28] J E Harries A Janbakhsh S Jobling P Matthiessen J PSumpter and C R Tyler ldquoEstrogenic potency of effluentfrom two sewage treatment works in the United KingdomrdquoEnvironmental Toxicology and Chemistry vol 18 no 5 pp 932ndash937 1999

[29] H R Aerni B Kobler B V Rutishauser et al ldquoCombinedbiological and chemical assessment of estrogenic activities inwastewater treatment plant effluentsrdquoAnalytical and Bioanalyt-ical Chemistry vol 378 no 8 pp 688ndash696 2004

[30] C L Hsueh Y H Huang C C Wang and C Y ChenldquoDegradation of azo dyes using low iron concentration ofFenton and Fenton-like systemrdquo Chemosphere vol 58 no 10pp 1409ndash1414 2005

[31] H Hansson F Kaczala M Marques and W Hogland ldquoPhoto-Fenton and Fenton oxidation of recalcitrant industrial wastew-ater using nanoscale zero-valent ironrdquo International Journal ofPhotoenergy vol 2012 Article ID 531076 11 pages 2012

International Journal of

AerospaceEngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

RoboticsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014


Active and Passive Electronic Components

Control Scienceand Engineering

Journal of



RotatingMachinery


Hindawi Publishing Corporation httpwwwhindawicom

Journal ofEngineeringVolume 2014

Submit your manuscripts athttpwwwhindawicom

VLSI Design



Shock and Vibration


Civil EngineeringAdvances in

Acoustics and VibrationAdvances in



Electrical and Computer Engineering

Journal of

Advances inOptoElectronics


Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

SensorsJournal of


Modelling amp Simulation in EngineeringHindawi Publishing Corporation httpwwwhindawicom Volume 2014


Chemical EngineeringInternational Journal of Antennas and

Propagation




Navigation and Observation



DistributedSensor Networks



[1 4] ECDs and PPCPs have been detected in effluentsof sewage treatment plants (STPs) in different countries atconcentrations of up to 70 ngLminus1 for E1 64 ngLminus1 for E2 and42 ngLminus1 for EE2 and 63 120583gLminus1 for carbamazepine 27 120583gLminus1for triclosan and 53120583gLminus1 for aspirin [1 5 6] suggesting thatconventional treatmentmethods are not efficient in removinglow level EDCs and PPCPs

Human exposure to these chemicals in the environmentis of serious worry with unidentified long-term impacts Inthe past few decades research efforts to combat this problemhave grown immensely EDCs removal methods fall intothree categories physical removal (such as activated carbonsorptioncoagulation nanofiltration and reverse osmosis)biodegradation (membrane bioreactors activated sludge andweed beds) and advanced chemical oxidation processes(AOP) such as Fentonrsquos oxidation ozonationUVH

2O2 pho-

tocatalysis on TiO2 or a combination of these technologies

and chemical treatment method such as chlorine dioxideBiological methods such as membrane bioreactor and

activated sludge systems show inconsistency in removalefficiencies as it is highly dependent on the type of pollutanttemperature membrane matrix loads variability in loadsand quality of water to be treatedTheuse ofmembrane biore-actors (MBR) inwastewater treatment showedgt80 removalof the target EDCs and PPCPs (ZeeWeed-1 004 120583m hollowfiber ultrafiltration 0094m2 surface area 24 hrs hydraulicretention time corresponding to average flux of 43 Lmminus2 hminus1air flow rate of 150 Lminminus1) [7] Biological systems requirelong solid and hydraulic retention times and have a highhuman resource requirement for operation Adsorption ofcontaminant onto sludge is a significant removal mechanismhence requiring appropriate sludge treatment

Many researchers have demonstrated the effectiveness ofphysical methods such as activated carbon (granulated orpowder) and membranes towards the removal of a broadrange of EDCs and PPCPs from artificial and real wastewaterin the laboratory pilot- and full-scale plants A removal ofgt90 of several PPCPs and EDCs from a drinking watersource (spiked with 100 ngLminus1 each of targeted contaminants)by powdered (PAC) activated carbon at pilot scale withdynamic dosing of 35mgLminus1 PAC at 20ndash25∘C has beenreported [8] Similarly an evaluation of full-scale drinkingwater and wastewater treatment facilities utilizing granulatedactivated carbon technology showed that regularly regen-erated facilities were very effective in the removal of tracecontaminants whereas irregular regeneration was very poordue to fouling [6 8] Membrane filtration processes using acombination of reverse osmosis (RO) and nanofiltration (NF)have been reported with excellent removal (gt95) of targetcompounds whereas microfiltration and ultrafiltration arenot very effective [6 9] Notwithstanding this high removalefficiency physical methods only transfer the contaminationfrom one medium to another Additionally membrane andsorption technologies require frequent costly regenerationandor backwashing due to organic fouling and biofoulingas several compounds are often detectable in membranepermeates and carbon effluent hence limiting the adoptionof these technologies in the industry [6 8 9] Additionally

physical and biological processes generally generate sludgeor reject which is more contaminated than the originalwastewater and so require further treatment

AOPs involving the generation of radicals have gainedsignificant interest because of their excellent removal capa-bilities and their ability to decompose the micropollutantsrather than simply transferring from one medium to another[4 10ndash12] While ozonation [11 13 14] Fentonrsquos photo-Fentonrsquos [14 15] and solar photocatalysis [16] have shownexcellent performances operational costs of ozonation sys-tems remain high and the generation of sludge in homo-geneous Fentonrsquos system due to the formation of insolubleiron species coupled with restricted operational pH range(2ndash4) remains a problem Heterogeneous Fentonrsquos systemstherefore exhibit greater potential with regard to costs and nosludge generation However there is limited information onheterogeneous Fentonrsquos processes in the literature

The heterogeneous polyacrylonitrile (PAN) catalystH2O2has shown potential at lab scale in the treatment of syn-

thetic organic contaminants [17ndash19]This study aims to exam-ine the effectives of the heterogeneous PAN catalystH

2O2

at a pilot scale towards the removal of selected EDCs andPPCPs from pretreated (activated sludge treated) municipalwastewater The pretreated wastewater was obtained fromthree of Severn Trent Waterrsquos sewage works in the MidlandsUK Lump parameters such as chemical oxygen demand(COD) and total organic carbon (TOC) were determinedThe effectiveness of the system towards the removal of naturalhormones estrone (E1) and 17 120573-estradiol (E2) synthetichormone 17 120572-ethinylestradiol (EE2) and PPCPs such ascarbamazepine triclosan and aspirin detected in effluentsdischarges from the sewage treatment plants was investi-gated In this work the use of the heterogeneous PAN catalystin a continuous flow process and at pilot scale is beingreported for the first time Environmental legislation on thedischarge of emerging contaminants and micropollutants islikely to become tighter in the near future rendering thesearch for new effective treatment technologies relevant

2 Materials and Methods

21 Wastewater Source Severn Trent Water (STW) is amunicipal water companymdashserving over 8million customersacross the heart of the UK stretching from the Bristol Chan-nel to the Humber and frommid-Wales to the East MidlandsThe company treats around 27 billion litres of wastewaterand sewage each day from communities and businessesacross the region and the treated water is discharged intoneighbouring streams and rivers This is performed in about1018 sewage treatment works 20 surface water treatmentworks and about 43 sludge treatment facilities across theregion The pilot system was tested on sewage from threedifferent STW treatment works in the Midlands namely SiteA Site B and Site C The true names of the different siteshave not been included in this paper for security reasonsand data protection Wastewater used in this study had beenthrough physical treatment (screens and grit removal andprimary sedimentation tanks) activated sludge tanks andsecondary clarifiers (see Figure 1) The wastewater at this




Sandfiltration




Screeningsand grit


Secondarysludge

Primarysludge








3sdot6H2O




4-estrone 2 4 16 16-d






(a)


(b)


Estrone (E1)

OH3C

OH



HO




H

H

H

H

HO

CHHO


Carbamazepine

O


Aspirin

H3C

HO

O

O

O


TriclosanO

HO

Cl

Cl Cl














molar mass of O2

)

(1)


2



2O2was


119865 = (


120591

) (2)


2O2




3 Results






















12000

10000

8000

6000

4000

2000

000

Site ASite BSite C

Carb

amaz

epin

e

Asp

irin

Tric

losa

nE1 E2 EE2

Rem

oval

()




3with a











2+H+ (5)









2O2to receiving


2O2




(free radical)

minusL

(ferryl ion)

L H+Excess H2O2



L119909FeIII + H2O




Rem

oval

()

1200

1000

800

600

400

200

00

Site ASite BSite C









2O2with H

2O2 COD









1 )

0 13 23 30 38 45Unused

03

025

015

01

005

0

02

Resid

ual i

ron

cont

ent (

mm

ol



4 Conclusion


2O2decomposed





Acknowledgments


References





































RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation












Sandfiltration




Screeningsand grit


Secondarysludge

Primarysludge








3sdot6H2O




4-estrone 2 4 16 16-d






(a)


(b)


Estrone (E1)

OH3C

OH



HO




H

H

H

H

HO

CHHO


Carbamazepine

O


Aspirin

H3C

HO

O

O

O


TriclosanO

HO

Cl

Cl Cl














molar mass of O2

)

(1)


2



2O2was


119865 = (


120591

) (2)


2O2




3 Results






















12000

10000

8000

6000

4000

2000

000

Site ASite BSite C

Carb

amaz

epin

e

Asp

irin

Tric

losa

nE1 E2 EE2

Rem

oval

()




3with a











2+H+ (5)









2O2to receiving


2O2




(free radical)

minusL

(ferryl ion)

L H+Excess H2O2



L119909FeIII + H2O




Rem

oval

()

1200

1000

800

600

400

200

00

Site ASite BSite C









2O2with H

2O2 COD









1 )

0 13 23 30 38 45Unused

03

025

015

01

005

0

02

Resid

ual i

ron

cont

ent (

mm

ol



4 Conclusion


2O2decomposed





Acknowledgments


References





































RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation











(a)


(b)


Estrone (E1)

OH3C

OH



HO




H

H

H

H

HO

CHHO


Carbamazepine

O


Aspirin

H3C

HO

O

O

O


TriclosanO

HO

Cl

Cl Cl














molar mass of O2

)

(1)


2



2O2was


119865 = (


120591

) (2)


2O2




3 Results






















12000

10000

8000

6000

4000

2000

000

Site ASite BSite C

Carb

amaz

epin

e

Asp

irin

Tric

losa

nE1 E2 EE2

Rem

oval

()




3with a











2+H+ (5)









2O2to receiving


2O2




(free radical)

minusL

(ferryl ion)

L H+Excess H2O2



L119909FeIII + H2O




Rem

oval

()

1200

1000

800

600

400

200

00

Site ASite BSite C









2O2with H

2O2 COD









1 )

0 13 23 30 38 45Unused

03

025

015

01

005

0

02

Resid

ual i

ron

cont

ent (

mm

ol



4 Conclusion


2O2decomposed





Acknowledgments


References





































RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation



















molar mass of O2

)

(1)


2



2O2was


119865 = (


120591

) (2)


2O2




3 Results






















12000

10000

8000

6000

4000

2000

000

Site ASite BSite C

Carb

amaz

epin

e

Asp

irin

Tric

losa

nE1 E2 EE2

Rem

oval

()




3with a











2+H+ (5)









2O2to receiving


2O2




(free radical)

minusL

(ferryl ion)

L H+Excess H2O2



L119909FeIII + H2O




Rem

oval

()

1200

1000

800

600

400

200

00

Site ASite BSite C









2O2with H

2O2 COD









1 )

0 13 23 30 38 45Unused

03

025

015

01

005

0

02

Resid

ual i

ron

cont

ent (

mm

ol



4 Conclusion


2O2decomposed





Acknowledgments


References





































RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation

























12000

10000

8000

6000

4000

2000

000

Site ASite BSite C

Carb

amaz

epin

e

Asp

irin

Tric

losa

nE1 E2 EE2

Rem

oval

()




3with a











2+H+ (5)









2O2to receiving


2O2




(free radical)

minusL

(ferryl ion)

L H+Excess H2O2



L119909FeIII + H2O




Rem

oval

()

1200

1000

800

600

400

200

00

Site ASite BSite C









2O2with H

2O2 COD









1 )

0 13 23 30 38 45Unused

03

025

015

01

005

0

02

Resid

ual i

ron

cont

ent (

mm

ol



4 Conclusion


2O2decomposed





Acknowledgments


References





































RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










(free radical)

minusL

(ferryl ion)

L H+Excess H2O2



L119909FeIII + H2O




Rem

oval

()

1200

1000

800

600

400

200

00

Site ASite BSite C









2O2with H

2O2 COD









1 )

0 13 23 30 38 45Unused

03

025

015

01

005

0

02

Resid

ual i

ron

cont

ent (

mm

ol



4 Conclusion


2O2decomposed





Acknowledgments


References





































RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










1 )

0 13 23 30 38 45Unused

03

025

015

01

005

0

02

Resid

ual i

ron

cont

ent (

mm

ol



4 Conclusion


2O2decomposed





Acknowledgments


References





































RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation





























RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation









Research Article Pilot-Scale Removal of Trace Steroid...

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Transcript of Research Article Pilot-Scale Removal of Trace Steroid...