1 . . 5

* . , . .. 7

I

EVALUATION OF WATER-BASED, TERPENE

AND FREON DEGREASERS

BY STEVE EVANOFF, KATHY SINGER, AND HENRY WELTMAN

GENERAL DYNAMICS CORPORATION

FORT WORTH, TEXAS

FOR D I S C U S S I O N . A T THE

WASTE MINIMIZATION SYMPOSIUM

LOS ANGELES I CALIFORNIA

MAY 2 6 , 1988

, -

I *

EVALUATION OF WATER-BASED, TERPENE, AND FREON DEGREASERS

'!

BACKGROUND:

In January 1987 a program was initiated at the Fort Worth Division of General Dynamics {GD/DI) to evaluate alternate degreasers to replace trichLoroethylene (TCE) in the factory. listing by EPA of TCE as a toric air pollutant. tion an Air Force Hazard Finding Comxcittee recommended that GD/FW pursue this substitution.

TCE: 1-1-1 trichloroethane (TCA), Freons, and water-based alkaline or emulsion cleaners. TCA is used extensively! in the aircraft industry, especially in California, where TCE is prohibited. It was decided, however, that because TCA is also being investigated for toxicity, it would just be a matter of time before it also would be prohibited. Moreover, GDfFW has had some experience with TCA causing corrosion on both aircraft and process equipment. It was decided, there- fore to eliminate TCA from consideration, During the course of the program, another class of compounds became of inters=%, namely terpenes, and these were included in the evaluation.

The reason for this action was the proposed In addi-

Three alternatives were considered as replacements for

PROCEDURE AND RESULTS:

A test plan was written for the degreaser evalua+-' J i O n .

The program was divided into four phases (5ee Table I).

Phase I included procuring test samples for evaluation. Industrial surveys and contacts with all known vendors of cleaning compounds resulted in identifying the materials listed in Table 11, all of which were included in the evalua- tion. Note that the designations "GD" in the Quaker and Brulin products are because special formulations were developed by these companies to meet GDfFW's degreasing requirements. the contaminants currently being cleaned from parts by vapor degreasing at GD/FW. contaminants are listed in Table 111.

Another task in Phase I was to identify all of

A plant survey was conducted and the

Phase I1 was a cleaning efficiency evaluation of each candidate material. These tests consisted of applying each contaminant to aluminum panels and cleaning the panels in the test degreasers in laboratory-scale t a n k s . Mechanical cirzu- lation wa4 provided. Air-sparglng was investigated but w a E eliminated because of excessive foam in some of the cleaners and the difficulty of maintaining uniform air-sparging on all of the surfaces;. After immersion time intervals of 5, 10, and 15 minutes, the panels were evaluated for cleanliness.

1

%%- Three techniques were used: (1) water break, ( 2 ) observing panels under UV light (most of the contaminants fluoresce), and (3) immersing the panels in a solution of cupric chloride, where a uniform deposit of copper indicated a clean surface. If a contaminant was not cleaned, the temperature was increased until the degxeaser was effective. If increased temperature was still not effective, the concentration of the solution was increased. The panels were closely observed for staining or etching, especially at temperatures or concentra- tions above manufacturer's recommendations. When a concentra- tion-temperature combination was effective, tests were con- ducted at progressively lower temperatures until the cleaner was no longer effective. In this manner, a complete tempera- ture profile was obtained for each degreaser's effectiveness on each contaminant.

7---11

Phase I1 Results - Water-Based Decireasers - Of the 23 water-based cleaners tested, five exhibited the ability to clean all of the contaminants involved, except cosmolene, on which none were effective. These five degreasers were 25% Grace Daraclean 282, 20% Quaker 624 GD, 25% Brulin 815 GD, 8 oz/gal Turco 42-15 NC-LT plus 2% additive, and 20% Oakite Okemclean. The performance data of these degreasersj are shown in Tables IV-VIII. Table IX shows a summarized comparison of their efficiency.

It must be noted that the other 23 water-based .J-.-?f

degreasers were efficient on several of the contaminants and should not be "ruled out" by other companies who may be considering water-based degreasers. Sone of them may in fact be superior to the five identified if degreasing requirements other than those experienced at GD/FW are encountered. It is a150 possible that specific requirements at GD/FW may change as new forming Oil5 and machining lubricants are developed, in which case other degreasers may be superior. all of the cleaners will be made available to other aircraft companies on request.

Test data on

Table X shows additional chemical and physical prop- erties of the five degreasers named-. discussed as follows.

Significant factors are

Silicates generally have a reputation of effecting coat-

The VOC's in Turco 42-15 NC-LT are from the additive

ings adhesion. Phase I11 tests will determine this effect.

(diethylene glycol mono butyl ether). efficient on several of the contaminants without the additive

This cleaner was not

23: L- - The oil separation is an important factor Secause it is

related to re-cycle procedures. emulsified may be difficult to remove). The Oakite Okemcfean, which exhibited the best oil separation, apparently is the

(The oils %hat remain

2

,

most "alkaline" and least "emulsion", as is a150 indicated by ? H a b

The data tables presented show the efficiency of each of 19 degreasers for each of 18 contaminants at temperatures from 120° to 160°F. optimum operating conditions according to the contaminants involved. factory functions have been defined (see Table XI). applying the performance data established, the optimum operating conditions for each degreaser to each application area has been determined (see Table XII).

The tube-bending area requires special attention. is necessary to clean the inside of long, narrow tubes, with complex curves, normal procedures are ineffective. procedures such as ultrasonic cleaning and vacuum oven drying are being evaluated.

ultrasonics on cleaning efficiency of water-based degreasers. It was found that any of the contaminants involved, cosmolene, could be cleaned by any of the five listed degreaserls in 5 to 10 minutes at room temperature. practicality of this technique in very large tanks needs to be determined, but ultrasonics will no doubt find aFplication for specific problem areas. previously discussed).

Such a data base can be used to "tailor"

Specific degreasing requirements for various by

A s it

Special

Other tests were conducted to determine the effects of

except

The

(For example, cleaning tubes a5

Temene Decreasers - Terpenes are organic soLvents derived from citrus plants. They contain the chemical D- Limonene ( C 1 o ~ l ) . contain detergents to make the solvent miscible with water. They may be used in a concentrated or diluted form. cantrated solvent has a flash point of 117°F (closed cup) or 145'F (open cup). makes them a VOC. They are Slow dryiag, having a vapor pressure of 1 mm of mercury. odor, are biodegradable and non-toxic.

Commercial degreaser formulations also

The coa-

They are photochemically active, which

Terpenes have a strong citrus

The cleaning efficiency of terpene formulations was found to be excellent on most contaminants. were ineffective on mill marks and carbowax, they cleaned the other contaminants, except cosmolene, in 5 minutes immersion at room temperature. minutes.

Although they

Even cosmolene was removed in 30

Terpenes are being evaluated in the electronics industry to replace the u5e of Freons on =Ir-*-; ---t boards. also have applications in the airxaft industry. Besides potential use as a degreaser, they are being evaluated at GI)/ FW as a hand-wipe solvent and as a substitute for safety 501- vent (MIL-C-18718). A disadvantage of terpenes as an immersion degreaser is that the contaminants do not separate

They should

3

from the solvent and therefore the terpenes cannot be recycled. when the terpenes are used in a diluted form, but this has not given satisfactory results to date in our tests;.

that in most cases they axe effective degreasers. When test panels were immersed in the boiling liquia or in the vapor all of the listed contaminants were removed within 5 minutes %aXC@gt cosmolene, carbowax, and mill marks. No differences were observed between various Freon 113 formulations, that is the addition of small amounts of acetone, alcohols, or nitro- methane had no effect.

Some manufacturers claim that oils do separate

Freons - Evaluation of Freon 113 formulations showed

Prooram Status

Phases I and 11 of the program are complete; Phases I11 and IV are yet to be conducted. the five listed cleaners on coating's adhesion will be evaluated. Cleaned panels will be anodized and chem-filmed and tested for salt spray corrosion. Stress corrosion tests will be conducted by immersing C-ring specimens of various alloys into the test fluids.

Phase IV will consist of a pilot scale evaluation in the factory. Parts will be cleaned in scaled-up testr tanks (ZOO gal lons) and the cleaning efficiency and tank maintainability will be noted. establish re-cycle procedures for used solutions. considerations will also be investigated.

In Phase 111, the effects of

A significant part of Phase IV will be to Disposal

Following Phase IV tests, one or more of the candidate degreasers will be selected for full-scale implementation.

CONCLUSIONS:

Two phases of the four phase evalution have been com- ple3ed. Based on resulks to date, the following conclu~ions may be made. I

1) Several commercial water-based cleaners would be effective degreasers at General Dynamics/Fort Worth Division.

2 ) A data base has been established to tailor optimum operating conditions to particular degreasing requirements.

necessary for certain "problem parts" such as cleaning inner surfaces of long, narrow tubes.

3) Ultrasonics enhance cleaning efficiency and may be

4) Terpenes are efficient degreasers, but have the dis- advantages of containing VOC's and of not being re-cycleable.

5 ) Freons are efficient degreasers, but anticipated high

4

. .

costs and limited availability, because of international legislation, preclude their consideration.

* .. %.-, i3

5

TEST SEQUENCE

PI-IASE I1 - PRELIMINARY CLEANER EVALUATION/ OPTIMIZATION

PHASE I IDENTIFYICLASSIFY CONTAMINANTS

PI-IASE 111 PERFORMANCE CONFIRMATION

PHASE IV - FACTORY EVALUATION

87-3 019107

WATER-BASED DEGREASERS

AEROMARINE - BRULIN - GRACE

- HOUGHTON

KEY - HARRY MILLER

OAKITE -

U S POLYCHEMICAL - QUAKER

' 3- - w TURCO

TABLE 11

LIST OF MATERIALS EVALUATED

AEROCLEAN LT NATURE SOL 100, AGUO SOL, 815 O R , 815 GD

DARACLEAN 281, 282, 283

CERFA-KLEEN 5380, 5601

KEY CHZM 244B

IMMUNOL S-6-I

6 lB , 164, 166 , N S , NST, OKEMCLEAN, LIQUALIN, LADD, ENHANCE

CBA 276

POLYCHEM 1 1 4

624 GD

EMULKLENE, 42-15 NC-LT, 42-15 ADDITIVE

WITCO - CHEMEDIZE 740

TERPENE-BASED DEGREASERS

CITRAGOLD - 3n

PETROFEM- - BIOACT DG-I

T R I TON HEMO-SOL, HEMO-SOL E, HEMO-SOL W

FREONS

ALLIED - GENESOLV 5535

DUPONT - TF, TMS

U S POLYCHEMICAL - POLYCHEM 425

7

m

kg TABLE 111

6;

PLANT SURVEY REVEALED THESE. MATERIALS REQUIRE CLEANING FROM PARTS

PRESERVATIVE COMPOUNDS

MULTIFAK EP-2 (DIE FACES) VV-L-800 (TUBING) MIL-C-16173 (PARTS, TOOLS) COSMOLENE (TOOLS, EQUIPMENT)

c__ FORMING LUBRICANTS

DHOUGHTON 431 (DROP HAMMER) CASTOR OIL (DROP HAMMER) HOUGHTON 3105 (TUBE BENDING)

TITEN LUBE (BENDING) I-1OUGHTON 3108 (DROP HAMMER) CIMFLO .20 (MISC. FORMING) PETROLATUM (MISC. FORMING)

MIL-H-5606 (TUBE BENDING)

GENERAL MACHINING

JOHNSON WAX (STAMPING)

HONING OIL (GRINDING)

BEESWAX I DRILLING) TRIMSOL (COOLANT) CARBOWAX (HONEYCOMB)

WD-40 (CUTTING)

K-34 (CUTTING) TAP-FREE DRILLING)

14-12 (MACHINE OIL)

I

I AS RECEIVED METAL

MILL MARKS

SHOP DIRT RUST PREVENTATIVE' OIL

1 8 7 - 4 919107

L GENERA), __-_ - - FYNAMKZ Fod Worth Division TABULATION StlEET TABLE IV CLEANINCi EFFICIENCY OF 25% ORACE DARACLEAII 282

7-L- - =--I====- -e ---

150' _---- 5 -- lo I !

100° I 120° 1 130' 170' I 7 5 O 160' 5 10 11 ~.

i lo f ---

---- ---I H-I2 I

--:---I=- _ -

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R = RESIDIJE REEW NS t _____-- , I -I __ .~ . . ! I-- I ----- - .

II Q

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x 0

IN

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I

PARTMENT i L -

GENERAL DVNAM!cE Fort Worfh Division TAEULATION StiEET

----- ---.--.- TABLE V I CLEANINQ EFFICIEMCY OF 2511 bHULIN 815 GD

75O I looo ' ! - I

10 I 5 10 15 ~- ----.-- !I i 10 15'5 10 15 --

.-

I

I ..-

--

-I_

I.

L i

I

1- I .

Ld C Y 3 %&$

GENERAL DYNA-M-ICs Fort Worth Division TABLE VI1 CLEANING EFFICIENCY OF 8 OZ/GAL TURCO 42-15 - __ - - - - -. - - . P A R l l A E N T 05

F W P 2 0 4 8 - ~ - 7 l

TABULATION StIEET NC-LT PLUEj 2% ADDITIVE

===I ---

----I-- -- I __--

I-- -.--

I 1 I /

+ ! PARTMLNT I$

F W P 264l-4-79 I I . .

GENERAL ----- --. OVNAMlC_S Fort Worrh Division TABULATION StiEET TABLE V I 1 1 CLEANING EFFICIENCY OF 20% OAKITE OKELICLEAN

CONTAMINANT

JOHNSON \?AX COSPiOLEN E

___________._. .... ~

__I-

I --

--I _.. ___-

.- ._

CONTAMINANT

S-431

TITEN LUBE

C OSMOLEN E

;:?-2

:ASTOR

XDNEY OIL

Z;$FLO 20 SEES WAX

'CARBOWAX

XILL MARKS

CONTAMINANTS XSTED BELOW

TABLE IX

SUMMARIZED DATA - FIVE EFFECTIVE DEGREASERS IMMERSION TIME/TEMPERATURE TO REMOVE CONTAMINANT

25% GRACE 282

5 I 1200

5 I 130

INEFFECTIVE

140

120

120

130

130

140

120

120

20% QUAKER 624 GD

10 @ 130'

5 @ 150

INEFFECTIVE

5 A 120

10 @ 150

10 @ 160

5 8 140

5 I 140

5 @ 120

5 8 120

5 @ 120

25% BRULIN ,

815 GD

LO Q 140'

5 @ 150

INEFFECTIVE

5 @ 140

5 @ 150

5 8 150

5 8 140

5 @ 150

5 @ 120

5 @ 120

5 @ 120

8 OZ/GAL TURCO 42-15 %US ADDITIVE

10 Q 140°

5 I 140

INEFFECTIVE

5 @ 120

5 @ 130

5 I 140

5 @ 130

5 I 130

5 8 130

5 @ 120

5 8 120

CONTAMINANTS - H-12, H-3108, TRIMSOL, RUST PREY., HONING, 5606, JOHNSON WAX 700, SHOP DIRT -

20% OAKITE

OKEMCLEAN

S @ 150'

5 I 150

INEFFECTIVE

8 120

8 150

@ 140

@ 130

@ 150

@ 150

@ 120

@ 120

14

TABLE X

I

GRACE ! 282

P R O P E R T I E S O F F I V E E F F E C T I V E DEGREASERS -

I BRULIN ' Et15 GD P R O P E R T Y / C O M P O S I T I O N

LOW

Y E S

NO

NO

Y E S

MOME

MOD

NONE

11.5

NO

.00002 PARTIAL

SILICATES

P H O S P H A T E S

3UAKER 1 624 GD

voc ' s

T O X I C E M I S S I O N S

BIODEGRADABLE

ODOR

FOAM ( A I R S P A R G E R )

FOAM ( C f R C . PUMP)

p H (AT USZ D I L U T I O N ) '-

S T A I N

E T C H RATE (2024 ALUM), O I L S E P A R A T I O N

Y E S

NO

NO

NO

Y E S

C I T R U S

LOW

NONE

1 0 . 7

NO

NONE ' A R T I A L i-

Y E S

NO

NO

NO

Y E S

NONE

HEAVY

NONE

12.1

NO

,00001 P A R T I A L

TURCO 12-15 NC-LT

A D D I T I V E

NO

YES

YES

NO

Y E S

NONE

MOD

NONE

9.1

ABOVE 150'

,00006 P A R T I A L

I A K I T E XEMCLEAN

Y E S

Y E S

NO

NO

Y E S

NCNE

NONE

NONE

13.0

NO

00005 COMPLETE

15

T A B L E X I SPECIFIC DEGi iEASING REQUIRZXENTS

o COSMOLENE

o MILL MARKS

pRQP HAMMER AREA

o HOUGHTON 431

o HOUGHTON 3108

o H-12

o EP-2

MACHINE SHOPS

o WD-40

o HONING O I L

o K-34

HONWCOMB P R O C E S S I N G

o CARBOWAX

TUBE BENDING

0 vv-L-800

o HOUGHTON 3105 (HONEY O I L )

o R U S T P R E V E N T I V E OIL

o CASTOR O I L

o JOHNSON WAX 700

o PETROLATUM/CIMFLO 20

o OTHER WATER SOLUBLE O I L S

o T A P FREE

o B E E S ' W A X

o T R I M S O L

o M I L - H - 5 6 0 6

0 TITEN LUBE 1129

. - I

PRE-ANODIZE, CHEM-FILM, CHEM-MILL, BOND

o S H O P D I R T o OTHER L I G H T CONTAMINANTS

o F I N G E R P R I N T S

DE-ECALS, PAESIVATE STEZL AND TITANIYM

o SHOP D I R T o OTHER LIGXT CONTAMINANTS

o F I N G E 4 P R I N T S

16

- . .. - - .

.

APPLICATION AREA

INCOMING MATERIALS*

DROP HAMMER

I

MACHINE SHOP

c

GRACE 282

S MIN @ 120'

5 @ 140

5 @ 130

TABLE XI1 APPLICATION OF DEGREASERS FOR EPECIFIC AREAS

QUAKER 624 GD %

BRULXN TURCO 42-15 OAKITE 215 GD PLUS ADDITIVE OKEMCLEAN

I

3 MIN @ 120'

HONEYCOMB

10 MIN 5 MIN @ 130' @ 120°

5 @ 140

10 @ 150

5 @ 160 OR

S @ 140

PRE-ANODIZE, ETC . I 5 @ 120

5 @ 2 5 0 10 @ 1 4 0 3 @ 2 5 0

5 @ 150 5 @ 130 s @ 150

I I I

I

5 @ 120 I 5 @ 120 I 5 e 130 I ' 5 @ 1 5 0

TUBE BENDING SPECIAL PROCEDURES BEING ESTABLISHED

* ALL CLEANERS INEFFECTIVE ON COSMOLENE

17