OXIDATIVE CARBONYLATION OF METHANOL TO DIMETHYL CARBONATE BY SOLID-STATE ION-EXCHANGED CUY CATALYSTS

The chloride free ion-exchanged Cu(II)Y is inactive for oxidative carb onylation of methanol to dimethyl carbonate. However, the Cu(I)Y as pr epared from a solid-state ion-exchange method is very active. Ammonia can facilitate the copper migration into zeolite cages at low temperat ure (150 degrees C). The reaction mechanism was studied by in-situ FTI R. The formation of copper methoxide in the zeolite cages during the o xidation of methanol is the first step. The insertion of carbon monoxi de into copper methoxide is the rate-limiting step. Methanol is requir ed for the desorption of dimethyl carbonate (DMC) in zeolite cages.