VERFAHREN ZUR HERSTELLUNG VON ALKYLENCARBONAT

A process for making alkylene carbonate by the reaction of carbon dioxide and an alkylene oxide of the formula wherein R, R1, R2 and R3 are one or more of hydrogen, alkyl, aryl, alkaryl, aralkyl, cycloalkyl, allyloxy, chloroalkyl, and aryloxy to produce the corresponding carbonate, which comprises: (a) providing a homogeneous liquid phase reaction zone in which the predominant material therein is the alkylene carbonate; (b) providing a catalytic amount of an alkylene oxide carbonation catalyst to said liquid phase; (c) having dissolved in said liquid phase sufficient CO2 to provide a molal amount therein which exceeds the molal amount of the catalyst; (d) providing a CO2 pressure in the reaction zone of between about 150 psig and about 750 psig; (e) maintaining a sufficient amount of the alkylene oxide in the reaction to maintain the pressure and temperature thereof; (f) maintaining the reaction zone at a temperature at which the alkylene oxide and CO2 react to form alkylene carbonate, which temperature is not greater than about 200 DEG C.; and (g) correlating the reaction zone temperature and pressure to yield an alkylene carbonate efficiency of at least about 99% and a conversion of at least 99.5%.