METHYLAMINE SYNTHESIS OVER SOLID ACID CATALYSTS - REACTION KINETIC MEASUREMENTS

Kinetic studies were performed over silica-alumina and acidic zeolites to determine the effects of temperature (from 600 to 700 K) and react ant pressures (<80 Torr) on the rates of methylamine synthesis from me thanol and ammonia. Related kinetic studies were conducted of methylam ine disproportionation reactions, methanol dehydration, and reactions of methanol and dimethyl ether with methylamines. The results suggest that the reactive species for methylamine synthesis are adsorbed nitro genous bases, while methoxy groups are reactive species for dimethyl e ther production. Disproportionation reactions may be important pathway s for the production of the higher-substituted amines during methylami ne synthesis. The combination of microcalorimetric measurements, repor ted elsewhere, and kinetic studies suggests that acid sites are requir ed in these reactions for the strong adsorption of ammonia and methyla mines, and weak adsorption sites are required to facilitate desorption of adsorbed amine species from the acid sites.