A highly efficient single site Rh-POL-PPh3 catalyst for heterogeneous methanol carbonylation

In Contrast to the Monsanto homogeneous system, the Rh heterogeneous methanol carbonylation universally displays lower activity and stability. Here, a single site catalyst Rh-POL-PPh3 was successfully prepared by impregnation of the Rh-2(CO)(4)C-12 dichloromethane solution, and applied to heterogeneous methanol carbonylation in a continuous fixed-bed reactor for the first time. Due to single site Rh species and the electron-donating effect of P ligands and the strong multicoordination bonds between Rh and P, the Rh-POL-PPh3 catalyst exhibited a little higher TOF of 1550 h(-1) than that of optimized Monsanto process and maintained relatively stable activity for near 180 h under 2.5 MPa, 195 degrees C. Thus, POL-PPh3 not only acts as a stable support but also a promotion of methanol carbonylation process. (C) 2017 Elsevier B.V. All rights reserved