Synthesis of alcohols from carbon oxides and hydrogen: VIII. A temperature-programmed reaction study of n-butanal on a ZnCrO catalyst

Abstract

The interaction of n-butanal with a ZnCrO catalyst has been studied by temperature-programmed reaction. Using combined GC, GC-FTIR, and GC-MS techniques, a large number of desorption products have been identified, including 1-butanol, C 8 and C 12 aldehydes, C 7 and C 8 ketones, and C 3, C 4, and C 7 olefins, as well as CO 2, dienes, trienes, aromatics, and light hydrocarbons. The formation of most products is explained by assuming surface reactions of two classes of intermediate species originating from the adsorption of n-butanal and from the surface aldol-like condensation of two molecules of n-butanal. Results indicate that the ZnCr oxide catalyst is active in performing aldehyde condensation, hydrogenation, hydrolysis, dehydrogenation, decarboxylation, and dehydration, along with isomerization and cracking reactions. Different functionalities are associated with different temperature ranges. The detected chemical functionalities are discussed with respect to their relevance to the direct synthesis of methanol and higher alcohols from CO and H 2.