Reaction Between Methanol and Commercial Seed Oils Under Microwave Irradiation

Abstract

The transformation of triglycerides, contained in a commercial seed oil into methyl esters, was studied in the presence of microwave irradiation and the results were compared with those obtained using traditional methods. This reaction is quite rapid using conventional and microwave heating; shorter reaction times were observed under microwaves in the presence of a variety of catalysts and the reaction was found practically complete in less than 2 minutes in most cases. Longer irradiation times in the absence of catalysts yielded increasing amounts offree acids, as detected by gas chromatography. The catalytic be of sodium methylate, sodium hydroxide, sodium carbonate, sulfuric acid, benzensulfonic acid and boron carbide was briefly discussed. The carbide provides an effective catalysis of the trans-estenfication in the presence of microwaves, without leaving traces of acidic or basic by-products. A lab scale plant for a continuous transestenfication process was also described.