Production of solketal from glycerol : effect of water removal and its use in preparation of benzyl solketal ether

Abstract

In the past, petrochemical industry had been a major producer of glycerol. Because of the high growth of biodiesel, glycerol is also produced at the same growing rate. This situation brings the price of glycerol to drop dramatically. Therefore, it should be a way to increase value of this by-product. Glycerol can be used in various manufacturers for example: food industry, cosmetic, plastic, drug, and etc. Solketal is a useful derivative which can be blended in gasoline or biodiesel for fuel additives, or used in synthesis of mono-, di-, triglycerides. The purpose of this work is divided into two parts. First is the study of using acid catalyst and molecular sieve 3A to increase the yield of solketal from reaction of glycerol and acetone. The reaction can be completed within 6 hours by using 1:6 of glycerol to acetone molar ratio. Subsequently, the prepared solketal was used to synthesize benzyl solketal ether by performing reaction with benzyl alcohol. There are many by-products in this reaction, for example: glycerol, acetone, dibenzyl ether and benzyl glycerol ether. The 4:1 solketal to benzyl alcohol molar ratio increases selectivity toward benzyl solketal ether (52.2%selectivity at 12 hour).