A new catalyst for an old process driven by environmental issues

The large-scale commercial production of phosgene for the manufacture of pharmaceuticals, agrochemical, polyurethane and polycarbonates occurs over carbon catalysts and has been practiced worldwide for more than 70 years [1] . These catalysts are traditionally derived from conventional carbon materials, such as coconut shells. Although carbon as a catalyst is extremely selective, 100–1,000 parts per million of carbon tetrachloride are produced as a byproduct in this process. DuPont now has developed a new commercial catalyst that reduces the carbon tetrachloride level by an order of magnitude. The catalyst has been scaled up from the laboratory to commercial production without any problems. Lifetime of the new catalyst is also 5 to 10 times longer than that of the conventional coconut based carbons. This presentation will outline the experimental program, some characterization details and a possible mechanism for CCl 4 production. This is a rare example of how good science has resulted in the discovery of a new catalyst for an old process that eliminates an environmental issue with no investment.