Efficient preparation of salicylonitrile from methyl salicylate over supported boron phosphate catalyst in a continuous fixed bed reactor.

SiO₂-supported BPO₄ catalysts have been prepared via a convenient one-pot process, characterized by XRD, N₂ adsorption/desorption, FTIR, and NH₃-TPD and investigated in the production of salicylonitrile using methyl salicylate and ammonia as the raw material in a vapor-phase fixed bed process. The results indicated that supporting BPO₄ in SiO₂ could increase the surface area and the amount of the moderate-to-strong acidic sites on surface, which markedly improved the catalytic performance. The effects of various reaction conditions, the effects of compositions on the catalytic activity, and the stability of the process have been studied in detail. Under the optimized conditions, an excellent 91.6% yield of salicylonitrile could be obtained, and good stability for the process was observed. The present study would provide foundation for industrial production of salicylonitrile. SiO₂-supported BPO₄ catalysts have been prepared via a convenient one-pot process, providing an excellent 91.6% yield of salicylonitrile using methyl salicylate and ammonia as the raw material in a vapor-phase fixed bed process. The result indicated that supporting BPO₄ in SiO₂ could increase the surface area and the amount of the moderate-to-strong acidic sites on surface, which markedly improved the catalytic performance. [ABSTRACT FROM AUTHOR]