(69a) Formation of Glycerol Derivatives by Catalytic Condensation and Acetalization

Conversion of glycerol into high valued chemicals has been the focus of many recent researches due to exponential growth in biodiesel production in the world. Condensation to higher alcohols and acetalization with aldols to produce cyclic acetals are possible alternative routes to utilize low grade glycerol for fine chemicals. Catalysts and reaction conditions are critical factors that determine reaction pathways and products distribution. H-ZSM-5, Cu-ZSM-5 and CuCr based catalysts and different reaction media were selected for this research. Results indicate that higher alcohols (> C4) and various cyclic acetals, mainly the 1,3-dioxolane and its derivatives, were formed under various reaction conditions. ZSM-5 zeolite was found to promote the formation of cyclic acetals. Reductive atmosphere up to 68 bars of H2 did not significantly alternate the product distribution. The intra-molecular dehydration of glycerol is assumed to be an initial step leading to an aldol-condensation chain growth where methanol is likely involved. More selective catalysts will be needed to obtain certain targeted products.