REACTION-RATES FOR THE PARTIAL DEHYDRATION OF GLUCOSE TO ORGANIC-ACIDS IN SOLID-ACID, MOLECULAR-SIEVING CATALYST POWDERS

Molecular-sieving catalysts have the potential to promote the producti on of oxygenated hydrocarbons from glucose. A kinetic model for the pa rtial dehydration of glucose to organic acids by micro- and mesoporous aluminosilicate catalysts was developed. Kinetic parameters were esti mated from glucose conversion and product yield versus time data at 15 0 degrees C for HY-zeolite, aluminum-pillared montmorillonite, MCM-20 and MCM-41 catalyst powders of 0.5 mmol H+ g(-1) solid-acid activity, Rate constants for the partial dehydration of glucose to 5-hydroxymeth ylfurfural (HMF) and the rehydration and cleavage of HMF to formic aci d and 4-oxopentanoic acid were maximized at catalyst pore diameters of 10-30 Angstrom. The final organic acid product yields were low, less than 60% of theoretical for formic acid and 10% of theoretical for 4-o xopentanoic acid, due to significant coke formation.