New catalyst for the conversion of glycerol generated by bio-diesel production into a fuel constituent

Inorganic-organic composites based on mesoporous MCM-41 were synthesized and successfully applied as catalyst for the condensation of glycerol with acetone into solketal, a fuel constituent. During the process of bio-diesel production great amounts of low-quality glycerol arise. The base material MCM-41 had a low activity due to the slightly acidic silanol groups on the surface, which led to a conversion of 8%. However, the silylized form was completely inactive, which could be explained by the hydrophobic properties of the surface and the missing acidic centers. After sulfonation of the composite material with sulfuric acid, the conversion was ∼ 38%. The same conversion was realized in the presence of p-toluenesulfonic acid. This is an abstract of a paper presented at the DGMK Conference: Future Feedstocks for Fuels and Chemicals (Berlin, Germany 9/29/2008-10/1/2008).