US Patent 7365214 Process for the preparation of cyclic carbonates

The present invention provides an improved process for the preparation of cyclic carbonates which comprises reacting an olefins or its epoxide with carbon dioxide or a mixture of oxygen-containing compound and carbon dioxide, in the presence of zeolite-based catalyst and a Lewis base co-catalyst, at a minimum pressure of 30 psig and temperature between 40 to 120° C. for 0.5 to 4 hrs., separating the catalyst and recovering the corresponding cyclic carbonate formed by conventional methods.