摘要 : At present, a large amount of biodiesel is produced from the non-edible and waste cooking oils using alcohol and catalyst (acid, alkaline). The free fatty acids in the oils react fast with the alkaline catalyst to produce soap tha... 展开 At present, a large amount of biodiesel is produced from the non-edible and waste cooking oils using alcohol and catalyst (acid, alkaline). The free fatty acids in the oils react fast with the alkaline catalyst to produce soap that inhibits the reaction. In the present work, a two-step trans-esterification process is developed to convert the high free fatty acid oils to its mono-esters. In the first step, acid catalyzed esterification reduces the free fatty acid level of the oil to less than 1.9%, and the alkaline catalyzed trans-esterification process converts the yields of the first step to its mono-esters and glycerol during the second step. The main factors such as alcohol and oil a molar ratio, catalyst amount, reaction time and temperature are optimized. The property of biodiesel obtained is similar to that of petro-diesel. 收起