Polymer-derived carbon-supported group VIII metals catalysts for vapor phase carbonylation of methanol

Abstract

Porous carbon beads (CB) prepared by carbonizing poly(vinylidene chloride) were used to support group VIII metals for vapor phase carbonylation of methanol. Compared with other typical activated carbon (AC), many new properties were developed during synthesis and carbonization processes. Novel active centers were introduced on the surface by the presence of two heteroatoms (Si, O) from bentonite; the active centers are thermally stable and affect the final metals dispersion. The dispersion of supported metals on CB at different temperatures was characterized by X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The thermally stable active centers enhance the stability of the supported metals particles. Three catalysts prepared on CB and two catalysts prepared on AC were tested in a fixed bed reactor. Activity and thermal stability of the catalysts were evaluated. CB presented excellent support performance. The second components such as Al, Zn, Sn and rare earth elements were introduced, Al and Zn are catalyst poisons, Sn and REE are catalyst promoters.