Study On Preparation Of Microbial Biodiesel

Microorganism grease is used as raw material in this paper.On account of microorganism grease is rich in polyunsaturated fatty acids(PUFAs),the separation and purification of PUFAs from microorganism grease,the remainder fatty acid will be used to microbial biodiesel.The issue of costing can be solved in the way.This paper systematically studied the physic-chemical properties of microorganism grease,the separation and purification of PUFAs,preparation of microbial biodiesel by microorganism grease.This paper dealed with the determining of the physic-chemical properties of microorganism grease including specific gravity,refractive index,acid value, saponification value,peroxidation value,iodine value,water component.By means of GC/MS analysis of microorganism grease,oleic acid accounts for 53.44%, linoleic acid accounts for 21.27%,hexadecanoic acid accounts for 11.57%,γ-linolic acid(GLA) accounts for 6.80%was obtained.The separation and purification of PUFAs from microorganism grease (Mortierella isabellina)via urea complexation was studied.The optimum technical condition was obtained as follows:weight ratio for fatty acid to urea to methanol was 1:3.5:10.5.crystal temperature was -5℃and crystal time was 20 hours.The process of microbial biodiesel production was optimized by application of the factorial design and response surface methodology(RSM) to obtain the optimum conditions for microbial biodiesel synthesis.Microorganism grease is used as raw material,sodium methylate as catalyst.The results showed that the optimum reaction conditions were:molar ratio of methanol to oil 7.85:1,catalysts 0.95g NaOH/100g microorganism grease,reaction time 117min,reaction temperature 60.75℃.The production analysis showed that the physical and chemical characteristics of the product were closer to diesel fuel,which made them a good substitute for diesel fuel.