Vapor phase coupling of n-butanol over the mixed catalyst system PdZn/SiO2+TiO2

Authors: Wegener, Evan

Submitted to: Illinois Heartland American Chemical Society (ACS) Regional Conference
Publication Type: Abstract Only
Publication Acceptance Date: 10/25/2024
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: The vapor phase reactions of n-butanol over a bimetallic PdZn/SiO2 catalyst and physical mixtures of PdZn/SiO2 and TiO2 were studied. The bimetallic catalyst was highly selective (>97%) for n-butanol dehydrogenation without the subsequent decarbonylation of butanal which is characteristic of monometallic Pd nanoparticles. When combined with TiO2, a known aldol condensation catalyst, the bifunctional system performs Guerbet-type coupling reactions and produces mixtures of C8 oxygenates and higher-order products including C7, C8, and C12 hydrocarbons. Within the reaction network PdZn/SiO2 performs dehydrogenation/hydrogenation reactions and decarbonylates C8 aldehydes to form C7 hydrocarbons. TiO2 catalyzes aldol condensation and the alcohol dehydration reactions responsible for producing the C8 and C12 hydrocarbons that constitute the majority of the secondary Guerbet products. This work demonstrates the ability of bimetallic Pd-based catalysts that are selective for alcohol dehydrogenation to participate in Guerbet-type coupling reactions and shows that their combination with an appropriate aldol condensation/dehydration catalyst is an effective strategy to produce higher molecular weight oxygenates and hydrocarbons.