Catalytic production of petrochemical products from bio-alcohols

Abstract

Large-scale petrochemicals are typically produced using petroleum olefins as a feedstock. The desire to move toward a sustainable and environmentally friendly chemical industry has lead to interest in the use of bio-derived feedstocks such as alcohols which are currently being produced on an increasingly large scale by fermentation or from synthesis gas. The research investigated the direct catalytic production of ethylene, acetaldehyde, ethylene dichloride (EDC), and ethylene oxide (EO) from ethanol. Two approaches were considered: a) the use of a bi-functional catalyst that combines the dehydration capability with ethylene conversion and b) the use of a double catalytic bed system where ethanol was dehydrated over the 1st bed and the product ethylene was converted over the 2nd bed to yield the desired petrochemical product. The dehydration of ethanol was carried out over several zeolites at different operating temperatures, producing mainly ethylene and diethyl ether. The catalytic selective oxidation of ethanol was tested over silver and/or copper compounds supported on several zeolites. The effects of operating conditions, metal loading, and zeolite acidity were determined. High selectivity to acetaldehyde was achieved. Unfortunately, the direct production of EO from ethanol could not be achieved. The catalytic oxychlorination of ethanol was investigated using CuCl2 as the active compound and zeolites were used as either a support or as a pre-bed. EDC was produced via ethylene oxychlorination as well as the oxychlorination and disproportionation of ethyl chloride. The effects of operating conditions and CuCl2 loading were determined. Higher EDC yield was achieved over the dual-bed system compared to the bi-functional catalyst