Production of Biodiesel Using Dimethyl Carbonate as the Methylating Agent: A Glycerol-Free Biofuel

Monday, November 8, 2010: 5:20 PM
251 A Room (Salt Palace Convention Center)
Michael Miguez1, Tracy J. Benson2 and Samir Budhathoki2, (1)Dan F. Smith Department of Chemical Engineering, Lamar University, Beaumont, TX, (2)Chemical Engineering, Lamar University, Beaumont, TX

Biodiesel is currently produced to supplement the supply of petroleum diesel, and much research is performed to find more efficient means of production. Biodiesel offers some desirable properties over petroleum-based diesel, being both environmentally friendly and lubrication. Currently, biodiesel is produced by reacting triglycerides, chiefly oils from row crops, with methanol by means of different catalysts. The desired product is a mixture of fatty acid methyl esters (FAME's), but a glycerol byproduct is also generated. The glycerol has to be separated in downstream processes, which requires more equipment and process unit operations. Biodiesel can also be produced by reacting triglycerides with dimethyl carbonate (DMC). The DMC reaction generates a more desirable product than the methanol reaction, as it does not generate any products requiring downstream separations. This new type of reaction will be analyzed to determine which conditions work best to generate biodiesel. The DMC reaction is initially carried out at various temperatures with various catalysts in batch reactors to generate biodiesel. The specific products from reacting triglycerides with DMC in a 1:1 mole ratio are 2 moles of FAME's and 1 mole of a glycerol derivative which has one fatty acid group and a carbonate group attached. For simplification, it is referred to as a glycerol carbonate fatty acid ester. A GC-MS is used to analyze the products to determine the components generated. Once enough data is available to determine specific reaction conditions, a larger scale reactor will be designed to produce enough biodiesel to test for ASTM standards and eventually test in a diesel-powered pressure washer. Initial results have indicated that the DMC reaction has a higher transition state than the methanol process. However, modeling efforts using Aspen 7 have revealed an overall lower energy demand for the complete reaction/downstream process. Complete reaction and modeling results will be presented.

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See more of this Session: Developments in Biobased Alternative Fuels II
See more of this Group/Topical: Sustainable Engineering Forum