[ajax0604]

I recently studied the production of biodiesel where triglycerides are reacted with concentrated NaOH or KOH as the catalyst to make methyl esters. I was wondering, could the reaction still occur with an acid catalyst? Also, I am studying the formation of aspirin using concentrated sulfuric acid at the moment. Could the reaction occur with a base catalyst? In general, is there a preference for one type of catalyst over the other depending on the reaction? Thank you.

[Hunter2]

First the alkaline catalyst is sodium or potassium methylate 30% in methanol. Hydroxide will guide to soap. Acidic catalysts not working, because side reaction with water take place.