Preparation of Biodiesel from Rapeseed Oil

According to the orthogonal experiments, the optimal transesterification conditions for rapeseed oil and methanol catalyzed by NaOH to form biodiesel were investigated. After a further study of the effect of methanol grade and stirring speed on the transesterification, the following suitable conditions for transesterification of the rapeseed oil were obtained: molar ratio of methanol to oil 6:1, reaction temperature 40C, reaction time 1h and amount of catalyst NaOH 1.0% of the oil weight. Under those conditions the achieved biodiesel satisfies the requirement of Austria DIN V51. The transesterification of the rapeseed oil and methanol catalyzed by lipase was investigated too, but the results were not so satisfactory. It is found that when the biodiesel is mixed with 0# diesel, at low temperature the mixture has better flowability than 0# diesel.