Oxygen-activated gold as a green catalyst for selective methoxycarbonylation

A group of Harvard scientists led by Profs. Madix and Friend has developed a catalyst based on gold for very selective production of dimethyl carbonate. The new process is environmentally friendly and its advantages are threefold. First, it starts with inexpensive chemicals such methanol, oxygen and carbon monoxide and operates at low temperatures. Second, the catalyst is highly selective. Model studies show that nearly 100 percent of the starting materials got converted to dimethyl carbonate. Third, the gold catalyst can be easily recycled without using toxic organic solvents. Because only the gold surface acts as the catalyst, gold can be used in the form of thin films or nanoparticles to minimize material use while maintaining its catalytic capability. This innovation is not limited to the production of dimethyl carbonate and is applicable to other dialkyl carbonate production as well.

Applications

Dialkyl carbonates are widely used as solvents, reactive reagents, lubricants and fuel additives in industry. In particular, dimethyl carbonate is used as a green reagent for methylation and methoxycarbonylation. Large-scale industrial production of dimethyl carbonate was 170 tons/day in 1997 and worldwide demand far exceeds current production capacity. However, current processes to produce dimethyl carbonate either involve toxic reagents, undesirable chemical wastes or extreme reaction conditions. A green and selective process can help meet this huge demand.

Intellectual Property Status: Patent(s) Pending