Hydrodechlorination and further hydrogenation of 4-chlorophenol to cyclohexanone in water over Pd nanoparticles modified N-doped mesoporous carbon microspheres

Abstract

The development of new catalysts with high catalytic activity for the hydrodechlorination (HDC) of chlorophenols (CPs) in the industrial polluted water has recently triggered various research interests. In this study, a novel N-doped mesoporous carbon microspheres (N-MCM) was synthesized through a nanocasting route using the low-cost and widely available dicyandiamide as precursor and MCM-48 nanospheres as the hard template. The synthesized N-MCM material exhibited a large surface area of 120.8m2g−1, pore volume of 0.24cm3g−1, average pore size of 9.9nm and rich N content of 27.2wt%. The characterization results of FT-IR, Raman spectrum and XPS illustrated that N-MCM had graphitic-like structures consisted of carbon nitride heterocycles, as well as amino groups. When N-MCM was used as catalyst support, Pd nanoparticles could be well dispersed in the mesopores and on the surface of the N-MCM. And the Pd/N-MCM nanocatalyst showed excellent catalytic activity for the eco-friendly HDC of CPs under green conditions in 1h. While interestingly, when the reaction time was continued, the HDC product phenol can be further hydrogenated to a much more useful product (cyclohexanone) with selectivity above 85%.