Marta A. P. Langone

Biodiesel Fuel Production by the Transesterification Reaction of Soybean Oil Using Immobilized Lipase

The enzymatic alcoholysis of soybean oil with methanol and ethanol was investigated using a commercial, immobilized lipase (Lipozyme RMIM). The effect of alcohol (methanol or ethanol), enzyme concentration, molar ratio of alcohol to soybean oil, solvent, and temperature on biodiesel production was determined. The best conditions were obtained in a solvent-free system with ethanol/oil molar ratio of 3.0, temperature of 50°C, and enzyme concentration of 7.0% (w/w). Three-step batch ethanolysis was most effective for the production of biodiesel. Ethyl esters yield was about 60% after 4 h of reaction.

Enzymatic Biodiesel Synthesis Using a Byproduct Obtained from Palm Oil Refining

An alternative route to produce biodiesel is based on esterification of free fatty acids present in byproducts obtained from vegetable oil refining, such as palm oil fatty acid distillate (PFAD). PFAD is a byproduct of the production of edible palm oil, which contains 96 wt.% of free fatty acids. The purpose of this work was to study biodiesel synthesis via esterification of PFAD with methanol and ethanol, catalyzed by commercial immobilized lipases (Novozym 435, Lipozyme RM-IM, and Lipozyme TL-IM), in a solvent-free system. The effects of reaction parameters such as type of lipase, enzyme amount, type of alcohol, alcohol amount, and enzyme reuse were studied. Fatty acid conversion of 93% was obtained after 2.5 h of esterification reaction between PFAD and ethanol using 1.0 wt.% of Novozym 435 at 60°C.

Enzymatic Synthesis of Medium-Chain Triglycerides in a Solvent-Free System

The synthesis of tricaprylin, tricaprin, trilaurin, and trimyristin in a solvent-freesystem was conducted by mixing a commercial immobilized lipase (Lipozyme IM 20, Novo Nordisk, Bagsvaerd, Denmark) with the organic reactants (glycerol and fatty acids) in a 20-mL batch reactor with constant stirring. In a first set of experiments, the effect of water concentration (0–6%) on the reaction conversion was shown to be negligible. In a second set of experiments, the effects of temperature (70–90°C), fatty acid/glycerol molar ratio (1–5), and enzyme concentration (1–9%[w/w]) on the reaction conversion were determined by the application of a 3×3 experimental design. The reactions were carried out for 26 h and the nonpolar phase was analyzed by gas chromatography (GC). Appreciable levels of medium-chain triglycerides were achieved, except for tricaprylin. For the triglyceride production, higher selectivity was attained under the following conditions: molar ratio of 5, enzyme concentration of 5 or 9% (w/w) and temperatures of 70°C (Tricaprin), 80°C (trilaurin), and 90°C (trimyristin). Statistical analysis indicated that the fatty acid/glycerol molar ratio was the most significant variable affecting the synthesis of triglycerides.

Estolides Synthesis Catalyzed by Immobilized Lipases

Estolides are vegetable-oil-based lubricants obtained from oleic acid or any source of hydroxy fatty acids. In this work, the estolides synthesis from oleic acid and methyl ricinoleate (biodiesel from castor oil), using immobilized commercial lipases (Novozym 435, Lipozyme RM-IM, and Lipozyme TL-IM) in a solvent-free medium was investigated. Acid value was used to monitor the reaction progress by determining the consumption of acid present in the medium. Novozym 435 showed the best performance. Water removal improved the conversion. Novozym 435 was more active at atmospheric pressure. Novozym 435 was reused four times with conversion reaching 15% after the fourth reaction at 80°C. Estolides produced under the reaction conditions used in this work presented good properties, such as, low temperature properties as pour point (−24°C), viscosity (23.9 cSt at 40°C and 5.2 cSt at 100°C), and viscosity index (153).

Synthesis of monocaprin catalyzed by lipase.

The production of monoglyceride emulsifiers commonly employed in the food, cosmetic, and pharmaceutical industries can be catalyzed by lipases, biocatalysts that are becoming increasingly attractive in the enzyme market. The aim of this study was to produce monocaprin utilizing a commercial immobilized lipase (Lipozyme IM 20) through the direct esterification of capric acid and glycerol. Experiments were performed for 6 h in an open reactor and the products were analyzed by gas chromatography. The parameters investigated were the amount of enzyme, temperature, and molar ratio between the reagents (capric acid/glycerol). The experimental runs followed an experimental design generated using Statistica software. The results showed that all the parameters were significant and that monocaprin production was enhanced at the lower ranges of the tested variables. The best conditions established were 55 degrees C, 3% (w/w) enzyme concentration, and molar ratio of 1. The final product, obtained after 6 h of reaction, was 61.3% monocaprin, 19.9% dicaprin, and 18.8% capric acid. This composition satisfies the directives of the World Health Organization food emulsifiers, which requires that these mixtures have at least 70% mono- plus diglyceride, and a minimum of 30% monoacylglycerol.

Enzymatic synthesis of monolaurin

The aim of this study was to produce monolaurin utilizing a commercial immobilized lipase (Lipozyme IM-20; Novo Nordisk, Bagsvaerd, Denmark) through the direct esterification of lauric acid and glycerol in a solvent-free system. The influence of fatty acid/glycerol molar ratio, temperature, and Lipozyme (IM-20) concentration on the molar fraction of monolaurin were determined using an experimental design. The best conditions employed were 55°C, lauric acid/glycerol molar ratio of 1.0, and 3.0% (w/w) enzyme concentration. The final product, obtained after 6 h of reaction, was 45.5% monolaurin, 26.8% dilaurin, 3.1% trilaurin, and 24.6% lauric acid. The reusability of the enzyme was also studied.

Estudo do comportamento da lipase comercial Lipozyme RM IM em reações de esterificação para obtenção de biodiesel

The aim of this work was to study monoalkyl ester synthesis catalyzed by immobilized lipase Lipozyme RM IM via the esterification reaction. Yields of over 90% were obtained with butanol in esterification reactions with oleic acid. In the reactions with deodorizer distillates of vegetable oils and butanol, the conversion obtained was greater than 80% after 2.5 h. For the esterification reaction of palm fatty acid deodorizer distillate (PFAD) and butanol, seven reuse cycles of Lipozyme RM IM were carried out and the final conversion was 42% lower than the initial conversion.

Process Development for Production of Medium Chain Triglycerides Using Immobilized Lipase in a Solvent-Free System

The synthesis of tricaprylin, tricaprin, trilaurin, and trimyristin in a solvent-free system was conducted by mixing a commercial immobilized lipase with the organic reagents (glycerol and fatty acid) in a 20-mL batch reactor with constant stirring. The effects of temperature, fatty acid/glycerol molar ratio, and enzyme concentration on the reaction conversion were determined. The reactions were carried out for 26 h and the nonpolar phase was analyzed by gas chromatography. Appreciable levels of medium chain triglycerides were achieved, except for tricaprylin. The higher selectivity values for the production of triglycerides were attained under the following conditions: a fatty acid/glycerol molar ratio of 5; enzyme concentration of 5 or 9% (w/w); and temperatures of 70 degrees C (tricaprin), 80 degrees C (trilaurin), and 90 degrees C (trimyristin). After completion of the esterification reaction under these conditions, the recovery of the triglyceride and fatty acids, and the reusability of the enzyme were studied. The unreacted fatty acid and the produced triglyceride were satisfactorily recovered. The commercial immobilized lipase was used in 10 consecutive batch reactions at 80 degrees C, with 100% selectivity in the trilaurin and trimyristin synthesis. The possibility of enzyme reuse and the recovery of residual fatty acid are relevant results that contribute to increasing the viability of the process.

ENZYMATIC BIODIESEL SYNTHESIS FROM ACID OIL USING A LIPASE MIXTURE

Kelly C. N. R. Pedroa, Juliana M. Parreiraa, Igor N. Correiaa, Cristiane A. Henriquesa,* and Marta A. P. Langonea,b Departamento de Química Analítica, Instituto de Química, Universidade do Estado do Rio de Janeiro, Rua São Francisco Xavier, 524, 20550-900, Rio de Janeiro – RJ, Brasil Instituto Federal de Educação, Ciência e Tecnologia, Rua Senador Furtado, 121, 20260-100 Rio de Janeiro – RJ, Brasil