Trial Purpose:
To evaluate the effectiveness of a FAME + Methyl Lactate mixture in removing several production oils and greases from stainless steel coupons as a potential replacement for TCE using heated immersion.
Date Run:
04/04/2023Experiment Procedure:
Three stainless steel coupons were used for each of the five soils being tested for a total of 15 coupons. The initial weights of each coupon were recorded. The bottom third of every coupon was soiled by applying the corresponding soil with a swab. The dirty weights of each coupon were then recorded. The coupons were then subjected to heated immersion cleaning in a solution of Fatty Acid Methyl Ester 93% + Ethyl Lactate 7% for 15 minutes at 130 F, with a stir bar set to 200 rpm. After the coupons were cleaned, they were left to air dry overnight. The next morning, the clean weights of each coupon were taken
| Soil | Use | CAS |
| Milform OAK 7a International | Stamping and drawing fluid | 64742-53-6 / 68909-65-9 |
| Milform Oak 529 | Evaporative lubricant | 68551-17-7 / 123-95-5 / 127087-87-0 |
| Milform Oak 15a | Metalworking oil | 64742-44-5 / 64742-52-5 / 64742-55-8 |
| Milform Oak 15c | Metalworking oil | 64742-52-5 / 64742-53-6 |
| M4 |
Trial Results:
| Solvent | Substrate | Soil | Initial wt of cont. | Final wt of cont. | %Cont Removed | % AVG | % Overall |
| Fatty Acid methyl ester 93% + Ethyl lactate 7% | Stainless Steel | Oak 7a international | 0.0436 | 0.0382 | 12.39 | 5.67 | -23.57 |
| Oak 7a international | 0.0701 | 0.0710 | -1.28 | ||||
| Oak 7a international | 0.0711 | 0.0669 | 5.91 | ||||
| M4 | 0.9774 | 0.0732 | 92.51 | 87.95 | |||
| M4 | 0.4029 | 0.0445 | 88.96 | ||||
| M4 | 0.3993 | 0.0703 | 82.39 | ||||
| Oak 15C | 0.0755 | 0.1044 | -38.28 | -5.36 | |||
| Oak 15C | 0.0781 | 0.0613 | 21.51 | ||||
| Oak 15C | 0.0880 | 0.0874 | 0.68 | ||||
| Oak 15A | 0.1857 | 0.0645 | 65.27 | 65.94 | |||
| Oak 15A | 0.1610 | 0.0560 | 65.22 | ||||
| Oak 15A | 0.1818 | 0.0594 | 67.33 | ||||
| Oak 529 | 0.0381 | 0.0545 | -43.04 | -272.07 | |||
| Oak 529 | 0.0192 | 0.1843 | -859.90 | ||||
| Oak 529 | 0.0264 | 0.0035 | 86.74 |
After being allowed to air dry over night, it was observed that the coupons were still completely wet the next morning. The FAME + Methyl Lactate solution was unable to air dry, which is reflected in these measurements. In some cases, a larger amount of cleaner remained on the coupon than the amount of soil it removed, leading to a heavier clean weight than dirty weight for particular coupons.
Success Rating:
Results successful using TACT (time, agitation, concentration, and temperature, as well as rinsing and drying) and/or other cleaning chemistries examined.Conclusion:
In the application of heated immersion with an air drying overnight period, Fatty Acid Methyl Ester 93% + Methyl Lactate 7% was not an effective cleaner for removing production oil and grease. In future testing, a drying step may be needed to gather more accurate measurements.
