ACTIVITY AND SELECTIVITY OF SUPPORTED RH COMPLEX CATALYST IN CARBONYLATION OF NITROBENZENE

The activity and selectivity behaviour of Rh(py)3Cl3 and Rh(CO)Cl(PPh3 )2 complex catalysts on various supports for carbonylation of nitroben zene to methyl phenyl carbamate has been investigated. The best cataly tic activity was shown by Rh(PY)3Cl3 on gamma-Al2O3 and Rh(CO)Cl(PPh3) 2/zeolites catalysts. The effect of temperature, CO pressure and initi al concentration of nitrobenzene on conversion of nitrobenzene and sel ectivity to methyl phenyl carbamate was studied. The results have been compared with the corresponding homogeneous catalysts. Carbon monoxid e interaction with supported Rh catalyst was investigated using in-sit u FT-IR spectroscopy. A plausible mechanistic pathway for carbonylatio n of nitrobenzene has been proposed.