| Energy is vital to national economy, social development, and people’s daily life aswell. Presently, fossil fuel takes a dominant role in the whole energy system (about85%). However, two serious problems are found in fossil fuel, that is, the increasingpollution and its non-renewability. In face of the global pollution and energy shortagecaused by rapid economic development, biodiesel, as a renewable and steady energysource, has appeared and is expected to lessen the long reliance on fossil energy andensure a sustainable social and economic development.Xiangxi region in the western Hunan Province is rich in Cormus Wilsoniana. Thisdissertation discusses how to extract biodiesel from Cormus Wilsoniana fruit oilthrough transesterification. The main findings are as follows:1. The technology of extracting Cormus Wilsoniana fruit oil. Through thetechnology of microwave-aided extraction of Cormus Wilsoniana fruit oil, it is foundthat the optimal extraction process is when the microwave power is800W, withpetroleum ether as solvent, solid/liquid ratio1:3(g/g), and extracting5times. Also it isfound that the optimal ultrasonic-aided extraction process is when the solvent is hexane,and the ration of material/solvent is1:5(g/g), with an18-hour immersion time. Underthese conditions, the extraction rate of Cormus Wilsoniana fruit oil can reach as high as5.65%.2. The technology of refining-deacidification of Cormus Wilsoniana fruit oil.Experiments show that the optimal extraction process is when the liquid ratio is11:5(mL/g), and temperature34℃, with a15-minute extraction time. The extractiontimes will increase to meet the requirement of acid value, depending on the acid valueof the Cormus Wilsoniana fruit oil.3. The technology of preparation of biodiesel from Cormus Wilsoniana fruit oilthrough ultrasound-assisted transesterification. The results show that the optimal molarratio of methanol to Cormus Wilsoniana oil is6:1, ultrasound frequency50Hz,ultrasound power180W, and catalyst mass content1.1%, with60℃reactiontemperature and80-minute reaction time. Under these conditions, the transesterificationrate can reach96.24%, and the parameter of biodiesel prepared from CormusWilsoniana fruit oil is similar to that of0#diesel oil, with higher flash point and lowerash content. |
