Efficiency of different additives in improvement of oxidation stability of fatty acid methyl esters with different properties

This study evaluates six formulations in improving oxidation stability of different fatty acid methyl esters (MEs). Two MEs differed in the unsaturation levels as they were synthesized from different feedstocks: a blend of soybean and sunflower oils (SoSuME), and waste cooking oil (WCOME); they did not fulfill the requirements of the EN 14214 standard concerning the oxidation stability (~0.6 h) and some impurities. The third MEs (SoSuME-EN) were fully compliant with the standard. Five formulations were phenolic-based, containing single or mixed antioxidant compounds of different molecular structures; one was amine-based. Different dosages of the formulations were added to the ME samples (corresponding to the addition range ~50-48300 ppm). The MEs stability expressed as induction periods, IPs, determined by the Rancimat method, were used for calculation of stabilization factors, SFs, indicating the efficiency of the applied formulation. The formulation containing TBHQ was the most efficient concerning the lowest consumption rate and the highest SF achieved for the low quality ME. 2,2?-methylene-bis-(4-methyl-6-tert-butylphenol) was linked with higher antioxidant potency than amine-based formulation and the phenolic com-pounds with two bulky tert-butyl groups. Among 4 selected phenolic additives, BHT and 2,2?-methylene-bis-(4-methyl-6-tert-butylphenol) proved similar efficiency in SoSuME-EN (at ~500 ppm they produced SF~2), while it took twice of this amount for mixed butylphenols to achieve the same effect.

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Fat and oil derivatives. Fatty acid methyl esters (FAME). Determination of oxidation stability (accelerated oxidation test)

10.3403/02807000 ◽

2003 ◽

Cited By ~ 1

Keyword(s):

Fatty Acid ◽

Fatty Acid Methyl Esters ◽

Methyl Esters ◽

Oxidation Stability ◽

Accelerated Oxidation ◽

Oxidation Test ◽

Acid Methyl ◽

Oil Derivatives

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Evaluation of Dominant Parameters in Lipase Transesterification of Cottonseed Oil

Transactions of the ASABE ◽

10.13031/trans.13003 ◽

2019 ◽

Vol 62 (2) ◽

pp. 467-474 ◽

Cited By ~ 2

Author(s):

Stanley Anderson ◽

Terry Walker ◽

Bryan Moser ◽

Caye Drapcho ◽

Yi Zheng ◽

...

Keyword(s):

Fatty Acid ◽

Oxidative Stability ◽

Fatty Acid Methyl Esters ◽

Methyl Esters ◽

Cottonseed Oil ◽

Molar Ratio ◽

Chromatography Method ◽

Induction Periods ◽

Acid Methyl ◽

The Difference

Abstract. Eversa Transform was used as an enzymatic catalyst to transform glandless and crude (heavy pigment) cottonseed oils into biodiesel. The oils were reacted with methanol at a 6:1 molar ratio with modified amounts of water, lipase, and temperature. Reactions were conducted in the presence of lipase and water at doses of 2, 5, and 8 wt% and 1, 3, and 6 wt%, respectively. Product composition and conversion were determined using the gas chromatography method of ASTM D6584. Oxidative stability was determined following EN 15751. The conversion to fatty acid methyl esters averaged 98.5% across all samples. Temperature had the most significant effect on conversion (p < 0.0035). Lipase and water dosages did not affect conversion, while each had an effect with temperature that was significant across the difference between 3 and 1 wt% water content and between 8 and 5 wt% enzyme content between the two temperatures (p = 0.0018 and 0.0153), respectively. Induction periods (oxidative stability) of the glandless and crude cottonseed oils were significantly different, but there was no difference between the two oil conversions based on oil type. Keywords: Biodiesel, Cottonseed oil, Fatty acid methyl esters, Lipase, Oxidative stability, Transesterification.

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