Synthesis of Glycerol Carbonate from Glycerol and Dimethyl Carbonate Using Strongly Basic Anion-Exchange Styrene–Divinylbenzene Dowex Resins

Abstract

The synthesis of glycerol carbonate from glycerol and dimethyl carbonate when using strongly basic styrene–divinylbenzene anion-exchange resins Dowex 1 × 2, Dowex 1 × 4, and Dowex 1 × 8 in the OH-form is studied. The resins are characterized by different degrees of crosslinking of their polystyrene matrices (the contents of divinylbenzene are 2, 4, and 8 wt. %, respectively). Synthesis is performed at 90–105°C, and the molar ratio of dimethyl carbonate to glycerol is 2 : 1. The yield of glycerol carbonate is shown to depend on the degree of crosslinking of the anion-exchange resin, since it falls as the degree of crosslinking rises. The highest degree of the conversion of glycerol (95%) and its selectivity toward glycerol carbonate (45.5%) are observed when using Dowex 1 × 2 and the reaction proceeds at 105°C for a period of 5 h. Advantages of considered systems over other anion- and cation-exchange resins proposed in the literature are noted.