The hydrogenation of buta-1,3-diene on evaporated copper–nickel alloy films

Abstract

The activity of copper–nickel film catalysts for the hydrogenation of buta-1,3-diene to butenes was approximately constant throughout the range 3–97 atoms % nickel. Pure nickel was about two orders of magnitude more active than the alloys at 55°C, a finding which is tentatively ascribed to a difference in film texture. Pure copper is, in turn, less active than the alloys by at most one order of magnitude. Butene distribution patterns for the two pure metals resemble on the whole those of Phillipson, Wells, and Wilson (their ‘type A’) with copper showing its usual strong preference for 1,2-addition of hydrogen. The but-1-ene: but-2-ene ratio tends to increase with increasing copper content showing that π-diolefin attachment becomes more difficult. The alloys yield a cis:trans ratio of but-2-enes more similar to those of nickel than of copper and this is consistent with their acting as mixtures of the more active nickel catalytic centres and less active copper centres.