CATALYTIC PROPERTIES OF COPPER-EXCHANGED CLAYS FOR THE DEHYDROGENATION OF METHANOL TO METHYL FORMATE

Dehydrogenation of methanol to methyl formate was carried out using co pper-exchanged clays as catalysts, Methanol was selectively dehydrogen ated to methyl formate on copper-exchanged laponite and fluoro tetrasi licic mica. In contrast, copper-exchanged montmorillonite and saponite only catalyzed the dehydration to dimethyl ether, and methyl formate was not formed, due to their acidities. Copper-exchanged laponite exhi bited a higher dehydrogenation activity than copper-exchanged mica. Th is can be understood by considering the way in which their layers aggr egate. The dehydrogenation activity of copper-exchanged laponite catal yst increased with the temperature of thermal treatment. The desorptio n of water molecules coordinating to copper was found to be responsibl e for the increased activity.