Patent ID: 7279592

Claim:
A process for the production of dialkyl carbonate comprising the steps of: (a) feeding a stream comprising urea, alcohol, water and ammonium carbamate to a first reaction zone: (b) concurrently in said first reaction zone operated under conditions of temperature and pressure to, (i) react water with urea to form ammonium carbamate, (iii) decompose ammonium carbamate into ammonia and carbon dioxide, and (c) removing ammonia, carbon dioxide and alcohol from said first reaction zone; (d) removing urea and alcohol from said first reaction zone; (e) feeding said urea and alcohol to a second reaction zone; (f) reacting alcohol and urea in the presence of a homogeneous catalyst comprising an organotin complex compound of dialkylalkoxide in a high boiling solvent to form dialkyl carbonate and (g) removing dialkyl carbonate and alcohol from said second reaction zone.