Liquid Lipase-Catalyzed Esterification of Oleic Acid with Methanol for Biodiesel Production in the Presence of Superabsorbent Polymer: Optimization by Using Response Surface Methodology

Abstract

Liquid lipase-catalyzed esterification of fatty acids with methanol is a promising process for biodiesel production. However, water by-product from this process favors the reverse reaction, thus reducing the reaction yield. To address this, superabsorbent polymer (SAP) was used as a water-removal agent in the esterification in this study. SAP significantly enhanced the conversion yield compared with the reaction without SAP. The lipase-catalyzed esterification in the presence of SAP was then optimized by response surface methodology to maximize the reaction conversion. A maximum conversion of 96.73% was obtained at a temperature of 35.25 • C, methanol to oleic acid molar ratio of 3.44:1, SAP loading of 10.55%, and enzyme loading of 11.98%. Under these conditions, the Eversa Transform lipase could only be reused once. This study suggests that the liquid lipase-catalyzed esterification of fatty acids using SAP as a water-removal agent is an efficient process for producing biodiesel.

Immobilization of Eversa Lipase on Octyl Agarose Beads and Preliminary Characterization of Stability and Activity Features

“…Since then, the enzyme has been mainly used in biodiesel production [31][32][33][34][35][36][37][38]. In all these papers, the enzyme has been used in free form as recommended by the supplier.…”

Liquid lipase‐catalyzed hydrolysis of gac oil for fatty acid production: Optimization using response surface methodology

“…New liquid lipase formulations, such as Eversa Transform lipase, have recently been developed as low‐cost biocatalyst lipases for the transesterification reaction to overcome the limitations of immobilized lipase . The cost of liquid lipase is 30–50 times lower than that of immobilized lipase and the preparation of liquid lipase is much simpler .…”

“…New liquid lipase formulations, such as Eversa Transform lipase, have recently been developed as low-cost biocatalyst lipases for the transesterification reaction to overcome the limitations of immobilized lipase. 26,29,30 The cost of liquid lipase is 30-50 times lower than that of immobilized lipase and the preparation of liquid lipase is much simpler. 31 Using this homogeneous biocatalyst increases the number of efficient collisions between the enzyme and reactants, thus improving mass transfer and enzyme adsorption; the reaction rate is thus higher for liquid lipase.…”

Biofuel and Bioenergy Technology

“…This Special Issue of Energies on the subject of "Biofuel and Bioenergy Technology" contains the successful invited submissions . A total of twenty-seven technical papers which cover diversified biofuel and bioenergy technology related researches have shown critical results and contributed significant findings in biomass processing [1,2], bio-oil and biodiesel [3][4][5][6][7][8][9][10][11], syngas [12][13][14], biogas/methane [15][16][17][18][19], bioethanol and alcohol-based fuels [20][21][22], solid fuel [23][24][25] and also microbial fuel cell [13,26,27] developments.…”

“…Encinar et al [7] performed rapeseed transesterification with KOH catalyst as well as with the aid of ultrasound whereby the kinetic behavior obeyed a pseudo-first order trend. Liquid lipase-based esterification was attempted and optimized using RSM to enhance the usage of water removal agent in the system [11]. In Anwar et al's, [5] work, it was found that by blending papaya oil biodiesel with varying contents (5-20%) with diesel could improve the engine testing properties.…”