Chemical and Biomolecular Engineering Research and Publications


Date of this Version

January 1998


This is the preprint of the article published in the journal, © 1998 Advances in Environmental Research ,2 (2)1998,232 - 243. Advances in Environmental Research is now published with Pergamon, an imprint owned and published by © Elsevier Science Ltd, UK. Please visit web site at


Methyl esters of fatty acids (also known as biodiesel), made from the transesterification of vegetable oils and animal fats with methanol, have shown a lot of promise as alternative diesel fuels. Glycerol is the inevitable byproduct of the trans-esterification process. While there are existing markets for glycerol, a significant increase in availability of glycerol, re-sulting from the expanded use of vegetable oils and animal fats, would destabilize the glycerol market. Direct addition of glycerol to the fuel is not possible, however, derivatives of glycerol such as ethers have potential for use as additives with biodiesel, diesel or biodiesel-diesel blends. In this study. the etherification of glycerol with isobutylene was investigated. The preparation techniques for this process were optimized. The optimum conditions were determined to be at 80 "C, catalyst loading > 5 wt%, 1-2 h of reaction time, and a glycerol to isobutylene molar ratio of approximately 3. Physical properties of ethers of glycerol and different blends of ethers with diesel and biodiesel fuels were measured. Solubility studies determined that these additives are compatible with diesel and biodiesel fuels. A 20% blend of these additives with methyl esters resulted in a 5 "C reduction in cloud point and an 8% reduction in viscosity

Included in

Biomaterials Commons