The strong interaction
between Zn and La species was induced by the presence of
both basic and acid active sites which found to simultaneously
catalyze the fatty acid esterification and oil transesterification reactions
while minimizing oil and biodiesel hydrolysis. Approximately
of 96% of biodiesel content was yielded at the high reaction
temperature (220 C) after 3 h of reaction even with crude palm oil,
crude soybean oil, waste cooking oil, food-grade soybean oil with
3% water and 5% oleic acid addition