Anti-Coke Properties of Acid-Treated Bentonite-Supported Nickel-Boron Catalyst

Boron (B) was introduced into the Ni/acid treated bentonite (Ni/A-Bn) catalysts to improve the anti-coking ability of nickel-based catalyst in the hydrogenation of nitrobenzene. The results showed the optimal B amount was 0.75 wt% on the Ni/A-Bn, which was more active than the catalyst without B. During a 105-hour reaction, Ni-B/acid treated bentonite (Ni-B/A-Bn) obtained a high nitrobenzene conversion (>99%) and a high aniline selectivity. The lifetime of Ni-B/A-Bn with B amount of 0.75 wt% extended 45 h compared to the Ni/A-Bn. The addition of B into Ni/A-Bn decreased the NiO particle size, improved the dispersion of the active components, and decreased the carbon deposition. The combination of B and Ni prevented the coke on the metallic Ni in the nitrobenzene hydrogenation, reducing the carbon deposition on the surface of Ni-B/A-Bn.