Effect of Ni-Cu on the one-step mild pressure hydrogenation of 1, 4-butynediol

The deposition-precipitation method was employed for the purpose of bringing in metallic promoters into Ni/Al₂O₃ catalysts. The effects of various metallic promoters on the catalytic performance in 1, 4-butynediol (BYD) hydrogenation were investigated. Besides, the contents of the suitable promoter were further studied, which were combined with BET, XRD, H₂-TPR, EDX-MAPPING, TEM, XPS, and NH₃-TPD techniques, aimed at exploring physico-chemical characteristics in catalysts. As the findings suggested, the addition of different promoters substantially impacted the interaction between Ni²⁺ and support, acting as the key factor impacting the catalytic performance. The introduction of Cu and Fe had the potential to prominently lower the strong interaction between Ni²⁺ and support for the improvement of the BYD conversion of 95%. Furthermore, different contents of Cu were further studied and discovered that it was the phenomenon of hydrogen spillover arisen on Cu surfaces, efficiently lowering the interaction between Ni²⁺ and support. Nevertheless, the aggregation in Ni particles cannot be evitable, but for the existence of Ni-Cu alloying in Cu-added catalysts. As the Cu content reached up to 5%, the catalyst manifested the excellent catalytic performance in hydrogenation owing to the abundant amount of Ni⁰ active sites in the form of the high dispersion and the fitting acidity.