Rubber Seed Oil Extraction And Biodiesel Production By Immobilized Lipase

Rubber seed oil extraction was investigated using various solvents and extraction methods. The solvents included ethanol, diethyl ether, petroleum ether, n-butanol and n-hexane, and extraction methods included extraction in motionless, shaking, and ultrasonic-assisted process (UAP) conditions, and soxhlet extraction and circumfluence extraction. The effects of circumfluence temperature were also studied. The result showed that it was optimal to extract motionlessly 60-mesh-sieved rubber seed for 1h using petroleum ether. The yield of solvent extraction was 10% higher than that of three or four times machine-squeezed oil. Moreover, the solvent residue promoted significantly the later biodiesel conversion.The results for rubber seed oil refining were as follows: For the crude solvent-extracted oil, it was first degummed 20 min by 0.04% H3PO4 at 60℃, and neutralized 10 min by 0.15% CaCO₃, then treated with 5% bleaching clay, and refined oil could be obtained. For the machine-squeezed oil, it was first degummed 20 min by 0.04% H3PO4 at 90℃, and neutralized 10 min by 0.15% CaCO3, then treated with 15% bleaching clay, and refined oil could be obtained. Single sorbent was better than mixture sorbent in degumming and decoloring.According to the analysis of rubber seed oil, C16 and C18 were the main fatty acid components, acid value was 38.836mg/g, saponification value 198.784mg/g, iodine value 122.092g/g and it belonged to semi-dry oil. The average relative molecular weight of its glycerides and free fatty acids were 846.839 and 269.609, respectively.Biodiesel was prepared using refined squeezed oil. Some parameters, such as oil/ethanol ratio, lipase amount, temperature, shaking speed, organic solvent and of methanol adding mode, were investigated. The optimal technical conditions were as follows: oil/methanol ratio 25:1, lipase 17%, petroleum ether 40%, 40℃, 225rpm. The conversion rate of biodiesel was 28.88% under the above conditions, and it increased distinctly by adding methanol every a certain time. In addition, the effects of crude oils and refined oils from squeezed oil and extracted oil were studied. No obvious difference was observed in conversion rate for the four kinds of oils. Therefore, solvent-extracted oil from...