Microstructure and catalytic properties of rapidly solidified Al-28.5 at% Fe and Al-28.5 at% Co alloys applied for selective hydrogenation of phenylacetylene

The Al71.5Fe28.5 and Al71.5Co28.5 (at%) melt-spun alloys were examined in terms of microstructure evolution and catalytic response in the semihydrogenation reaction of phenylacetylene to styrene. In the as-spun state ribbons showed a single-phase composition. The Al71.5Co28.5 alloy contained columnar grains of a metastable decagonal quasicrystal, which transformed into hexagonal Al5Co2 and monoclinic Al3Co phases after heat treatment at 900 degrees C. The Al71.5Fe28.5 ribbon had an ordered orthorhombic Al5Fe2 phase structure in both the as-spun and annealed states. The pulverized ribbons revealed considerable catalytic activity for selective hydrogenation of phenylacetylene to styrene. The best results were achieved for the as-spun quasicrystalline Al71.5Co28.5 alloy, showing a conversion rate of above 80% after 2 h reaction time. The selectivity to styrene was 60% for all catalysts. The tested powders retained their phase composition following liquid reaction therefore the proposed materials can be considered for catalytic use.

Automated summary

The microstructure evolution and catalytic response of Al71.5Fe28.5 and Al71.5Co28.5 alloys were examined in the semihydrogenation reaction of phenylacetylene to styrene. The Al71.5Co28.5 alloy showed the best catalytic activity, achieving a conversion rate of over 80% after 2 hours of reaction time.