Study On Lipid Extraction And Long Chain Hydrocarbon Conversion Of Rhodotorula Glutinis

Oleaginous microorganisms have attracted attention because of their high lipid content,renewable energy and environmental friendliness.They are used in the preparation of biodiesel and biojet fuel.Due to the high lipid content and the unique fatty acid composition in comparison with microalgae,R.glutinis has its advantages in the production of biojet fuel.In this paper,it was explored that the direct oil extraction by various solvents from R.glutinis without cell-broken pretreatment for the first time.A 75%ethanol/n-hexane volume ratio of 3:1 was used due to the best lipid extraction content.The lipid extraction amount was 0.275 g/g biomass,and the extraction yield of lipids was 89.52%.The content of neutral lipids,glycolipids,and phospholipids were 77.37%,20.06%,and 2.57%of the total fatty acids,respectively.At the same time,the extracted yeast cells were characterized by Scanning Electron Microscopy and Fourier Infrared Spectroscopy.It was found that the oil extraction process was carried out without the cell wall being broken and the solvent had a certain influence on the membrane proteins and membrane lipids of the yeast cells.As a result,the permeability of cell walls and cell membranes was changed to achieve the purpose of oil extraction.Secondly,the study on preparation of the long-chain hydrocarbons was carried out by decarboxylation method.The substract and the catalyst was the the fatty acid composition of R.glutinis and 5%Pt/C,respectively.Meanwhile,the effect of the reaction time,temperature,solvents,catalyst and solvent dosage on the product production were explored,respectively.As a result,the contents of pentadecane,heptadecane and aromatic hydrocarbons obtained in the solvent-free system were 22.31%,44.86%and 26.83%,respectively;the contents of pentadecane,heptadecane and aromatic hydrocarbons obtained in the aqueous catalytic system were 18.31%,41.55%and 12.17%.When the protein content was 5%(wt,%)of the crude oil,the reaction was significantly inhibited;while the protein content was 2%(wt,%),the inhibitory effect was significantly weakened.The less pigment content in crude oil had less influence on the reaction.Finally,Aspen Plus simulation was performed on the process for oil extraction-long chain hydrocarbons production from R.glutinis.The process of R.glutinis(75.75%water content,wt)daily processing capacity of 1000 t was established.After the process of oil extraction,solid-liquid separation,solvent recovery,and decarboxylation,products of pentadecane,heptadecane and aromatics hydrocarbon were finally obtained and the content(kg/h)was 302.02,636.72,341.36,respectively;the energy consumption of the decarboxylation unit was 1336 MJ/t long-chain hydrocarbon,which was significantly lower than the energy consumption of the hydrodeoxygenation process;the total process energy consumption was 9577 MJ/t long-chain hydrocarbons.The process showed lower energy consumption and lower cost in terms of energy consumption and hydrogen consumption,and had certain potential for competition.