Optimization of Lipase-Catalyzed Transesterification of Cotton Seed Oil for Biodiesel Production Using Response Surface Methodology

Abstract

The aim of this work was to study the biodiesel production from cotton seed oil by lipase produced by Pichia guilliermondii lipase, which was immobilized onto hydrophobic magnetic particles (HMPs). The optimum reaction conditions were determined for lipase dosage, methanol-to-oil molar ratio, temperature and water content. Using response surface methodology, a quadratic polynomial equation was obtained for fatty acid methyl esters (FAMEs) content by multiple regression analysis. Verification experiments confirmed the validity of the predicted model. The optimal conditions for the enzymatic transesterification were temperature of 38.76 , 31.3% immobilized lipase, 10.4% water content, and a methanol-to-oil molar ratio of 4.715:1. The gas chromatography-mass spectrometry showed that biodiesel was mainly composed of the methyl esters of hexadecanoic, 9,12-octadecadienoic and 9-octadecadienoic acid.

Fe3O4-PDA-Lipase as Surface Functionalized Nano Biocatalyst for the Production of Biodiesel Using Waste Cooking Oil as Feedstock: Characterization and Process Optimization

“…GC-FID, having a highly-polar BPX-70 capillary column (30 m × 0.25 mm), was utilized for the analysis of products. The oven temperature was kept at 100 • C for 30 s, then raised to 250 • C at a rate of 10 • C/min, while the temperature of the detector was set at 270 • C. 500 ppm of sample was dissolved in hexane containing methyl heptadecanoate as an internal standard, and 1 µL of this mixture was injected in column [26,27]. The percentage conversion of biodiesel was calculated by given formula [28]…”

“…Similar conditions have also been investigated by other researchers. Ying and Dong obtained the maximum biodiesel yield using immobilized lipase with 31.3% nano-biocatalyst, 38 • C temperature and 4.7:1 methanol to oil ratio [27]. Thangaraj et al reported the maximum biodiesel yield of 89% at an optimum condition i.e., 1:3 methanol/oil ratio, 12 h of reaction period and 45 • C temp., using the immobilized NS81006 lipase as the catalyst [45].…”

“…2 and x 4 2 had significant effect on response. Li and Dong [27] selected methanol:oil x 1 , lipase:oil x 2 ,…”

“…Out of that, all the linear terms showed significant effect, while x1x2, x2x3, x3x4, x2x4, x1x4, and x4x5 were significant first order terms and among quadratic terms x3 2 and x4 2 had significant effect on response. Li and Dong [27] selected methanol:oil x1, lipase:oil x2, water content x3, and temperature x4 as independent variables for process optimization of biodiesel production using RSM. All the linear terms were significant in that model as well, which resembles the current study except the water content, which is insignificant in our work.…”

Enzymatic synthesis of ethyl esters from waste oil using mixtures of lipases in a plug‐flow packed‐bed continuous reactor

“…12 Among continuous reactors, the packed-bed reactor (PBR) is one of the simplest configurations, where the immobilized biocatalyst is trapped in the reactor, while the substrate solution is pumped through at a specific flow rate that will determine the residence time. [13][14][15][16] This configuration reduces the process cost, besides showing faster and higher catalytic activity compared to bioreactors using free enzymes. 1,17 The use of solvents in lipase-catalyzed transesterifications depends on the necessity of each process.…”