82 % of the world’s production of the noble metal rhodium, 51 % of the production of palladium, and 19 % of the rare earth metal cerium is presently used for the production of three-way catalysts for purifying exhaust gas of gasoline vehicles. The conversion of the pollutants takes place on the surface of the catalytically active material. Pd is known as very effective oxidation component for the conversion of CO and hydrocarbons, but as well for NO to NO2. Rh decreases the activation barrier for the reduction of NOx by CO. Much effort has been spent on replacing these metals by less expensive and more abundant materials. However, until today no breakthrough has been achieved.
Computer simulation is used by a research team led by Martin Votsmeier, Umicore, Hanau, Germany, to connect the chemical properties of the catalyst materials and the behavior of the catalyst. By this they hope to specifically optimize the individual catalyst materials for the best performance in the overall system to develop catalysts with a significantly reduced amount of precious metals and cerium, which still meet the requirements of emissions legislation.
Research in the field of automotive catalysis has a long standing tradition for the company in Hanau: In 1968, Edgar Koberstein, then Degussa, began research in the field of automotive catalysts. This was triggered by California’s requirements for vehicle emissions in the 70s. In 1972, Koberstein gained a patent for a catalyst for the purification of exhaust gases from motor vehicles and industrial plants. Umicore today ranks third in global market share.
Presented by Dr. Martin Votsmeier, Umicore AG & Co. KG, Hanau, Germany, at the Bunsentagung 2013 (112th General Assembly of the German Bunsen Society for Physical Chemistry) held in Karlsruhe, Germany.
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