The use of M@p(4‐VP) and M@p (VI) (M:Co, Ni, Cu) cryogel catalysts as reactor in a glass column in the reduction of p‐nitrophenol to p‐aminophenol under gravity

Abstract

AbstractIn this study, metal@p(4‐Vinyl pyridine) (M@p(4‐VP)) and metal@p (vinyl imidazole) (M@p (VI)) (M: Co, Ni, and Cu) cryogel catalysts as continuous reactor were used in reduction of p‐nitrophenol (p‐NP) to p‐amino phenol (p‐AP). The aqueous solution of p‐NP passed through these super porous cryogel catalysts under gravity, and reaction kinetic for p‐AP generation was investigated. The effect of metal species, amount of p‐NP solution, amount of metal nanoparticle (increased by loading/reducing cycles), and temperature on the reduction reaction for p‐NP to p‐AP catalyzed by M@p(4‐VP) and M@p (VI) cryogel catalysts were investigated. It was found that Co@p(4‐VP) and Co@p (VI) cryogel catalysts provided the best catalytic performances than the other used metal species with 2.19 and 1.37 mol p‐NP/(mol catalyst.min)−1 turn‐over frequency (TOF) values. Furthermore, in addition better TOF values, low Ea values of the prepared Co@p(4‐VP) and Co@p (VI) cryogel catalysts with the values of 18.9 ± 1.3, and 25.4 ± 1.8 kJ/mol were found to be better than most of the similar works reported in the literature.