Calcination-Free Synthesis of Porous Metal Oxides/Carbon from Calcium Carbide by Ball Milling

Calciumcarbide is a key intermediate in the chemicalindustry,such as cyanamide industry (>2 Mton year(-1) forCaCN(2)), and in the manufacture of vinyl chloride (& SIM;13Mtonyear(-1)). The environment-friendly utilization ofreactive CaC2 is of great interest. Herein, by ball millingCaC(2) and equimolar metal chlorides, porous carbon-supportedtransition-metal oxides were obtained without calcination treatment.This mechanochemical synthesis route was based on the CaC2 replacement reaction and the Cl--triggered free-radicalreaction. Different metal oxides including Mn3O4/C, Fe3O4/C, NiO x /C, Cu2O/C, ZnO/C, ZrO2/C, Nb2O5/C, CeO2/C, HfO2/C, and WO3/C showed high surface areas up to 232 m(2)g(-1). Moreover, the as-made metal oxides displayed good performance inheterogeneous catalysis. NiO x /C promotedselective nitrobenzene hydrogenation with high conversion and selectivity(>99% Conv., >99% Select.), while CuMnCeO x /C achieved 90% CO conversion at 120 & DEG;C in CO oxidation.

Automated summary

Porous carbon-supported transition-metal oxides were obtained without calcination treatment by ball milling CaC2 and metal chlorides. The as-made metal oxides showed high surface areas and exhibited good performance in heterogeneous catalysis.