Regulating Surface Acidity/Basicity by Hybrid Acid/Base Carrier for Selective Hydrogenation Isobutyraldehyde

Abstract

This research investigates the role of surface acidity and basicity in influencing the catalytic performance of nickel-supported catalysts for the selective hydrogenation of isobutyraldehyde (IBD) to isobutanol (IBA), an important industrial process for producing additives for pharmaceuticals and fuels. Nickel-based catalysts such as 60Ni/Al₂O₃, 60Ni/MgAlO, and 60Ni/MgO were synthesized, characterized, and evaluated for their catalytic activity and selectivity. The study employed microcalorimetric adsorption and Fourier-transform infrared spectroscopy (FTIR) to elucidate the interactions of IBD and IBA with the catalyst surfaces, providing insights into the effects of these interactions on catalytic behavior. The 60Ni/MgAlO catalyst demonstrated the higher activity and selectivity for IBA production, attributed to its optimal balance of surface acidity and basicity and a high density of active Ni sites. In contrast, 60Ni/Al₂O₃, despite its high intrinsic activity, showed lower selectivity due to side reactions at lower conversion. 60Ni/MgO exhibited limited activity, with a significant amount of IBD unconverted, leading to higher byproduct formation. These findings highlight the critical influence of surface properties on the hydrogenation process and underscore the potential for tailoring catalyst composition and surface characteristics to enhance selectivity and efficiency in industrial applications.