The carbonylation reaction of methanol catalyzed by the polymer bound Rh(I) complex formed by the ligand exchange of $RhCl(CO)(PPh_3)_2$ with the styrene-divinylbenzene copolymer containing bound $-CH_2PPh_2$ groups was compared with that catalyzed by its homogeneous counterpart, $RhCl_3ㆍ3H_2O$. The mathematical model was proposed to study the kinetics of the carbonylation reaction.
Kinetic experiments were also performed in a stirred batch reactor operating under the reaction conditions of potential industrial interest.
The carbonylation reaction showed approximately first order with respect to the concentrations of methyl iodide and Rh(I) complex and zero order with respect to each of methanol concentration and CO partial pressure.
Reaction rates were determined by the slow oxidative addition of methyl iodide to Rh(I) complex and the magnitude of reaction rates were observed to be the order of $10^{-3}$ (mole/lㆍmin) at 178℃.
The product in the carbonylation reaction was mainly acetic acid and by-product were dimethyl ether, water, and methyl acetate. However, by-products were converted to acetic acid at a complete conversion.
In the gel-form polymer bound catalyst, the intrinsic activity was found to vary with the crosslink density of polymer. The catalytic activity of polymer bound catalyst was found to be 60% of its homogeneous counterpart.
To study the effect of the pore size distribution on the catalytic properties of polymer bound catalyst, 1, 5, 10, 15, and 20 wt% crosslinked polystyrene-DVB copolymer were also prepared.
