A novel supported catalyst for the carbonylation of methanol

Porous carbon beads (Ys) prepared from poly(vinylidene chloride) are used a s Rh supports for the carbonylation of methanol. TEM and STM images show th at uniform pores spread over their surfaces. The optimum temperature for th e pyrolysis is 1000 degrees C. The special support has a specific surface a rea of 1000 m(2)/g with high mechanical strength and thermal stability. The average diameter of pore is in the range of 0.8-1.2 nm suitable for the fi ne spreading of Rh atoms. XPS spectra indicated that covalent bond is forme d between carbon and rhodium in the catalyst, which makes the loss of rhodi um become quite little. Catalytic carbonylation results show that the activ ity and selectivity of this catalyst very excellent. The influence of the e xternal and internal diffusion on the methanol carbonylation was detected. The effect of varying the temperature, concentration of CH,I, content of Ph , initial partial pressure of CO and added acetic acid was examined. (C) 19 99 Elsevier Science B.V. All rights reserved.