Kinetics studies for the synthesis of dimethyl carbonate from urea and methanol

A new route was proposed for producing dimethyl carbonate (DMC) from urea and methanol catalyzed by the organotin and the high boiling electron donor solvent as a co-catalyst. The effects of methanol/urea initial molar ratio, the mass percent of catalyst and solvent, the reaction time and the reaction temperature on the DMC yield were investigated. Experimental results indicated that the temperature is more important to the reaction and the content of solvent has little effect on DMC yield. Furthermore, too higher reaction temperature results in the consumption of DMC to form the N-alkyl by-products due to the high activity of DMC. Removing DMC and ammonia from the reaction system in time is vital to improving DMC yield. The kinetics model for this reaction system was developed. The calculated results using the parameters obtained from the genetic algorithm (GA) agree well with the experimental data. (C) 2004 Elsevier B.V. All rights reserved.