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A catalytic converter is an emissions control device that converts toxic pollutants in exhaust gas to less toxic pollutants by catalyzing a redox reaction (oxidation or reduction). Catalytic converters are used with internal combustion engines fueled by either petrol (gasoline) or diesel—including lean-burn engines as well as kerosene heaters and stoves. The first widespread introduction of catalytic converters was in the United States automobile market. To comply with the U.S. Environmental Protection Agency's stricter regulation of exhaust emissions, gasoline-powered vehicles starting with the 1975 model year must be equipped with catalytic converters. These "two-way" converters combined oxygen with carbon monoxide (CO) and unburned hydrocarbons (HC) to produce carbon dioxide (CO2) and water (H2O). In 1981, two-way catalytic converters were rendered obsolete by "three-way" converters that also reduce oxides of nitrogen (NOx);〔 however, two-way converters are still used for lean-burn engines. Although catalytic converters are most commonly applied to exhaust systems in automobiles, they are also used on electrical generators, forklifts, mining equipment, trucks, buses, locomotives and motorcycles. They are also used on some wood stoves to control emissions. This is usually in response to government regulation, either through direct environmental regulation or through health and safety regulations. == History == The catalytic converter was invented by Eugene Houdry, a French mechanical engineer and expert in catalytic oil refining, who moved to the United States in 1930. When the results of early studies of smog in Los Angeles were published, Houdry became concerned about the role of smoke stack exhaust and automobile exhaust in air pollution and founded a company called Oxy-Catalyst. Houdry first developed catalytic converters for smoke stacks called "cats" for short, and later developed catalytic converters for warehouse forklifts that used low grade, unleaded gasoline.〔"(Exhaust Gas Made Safe )" ''Popular Mechanics'', September 1951, p. 134, bottom of page〕 In the mid-1950s, he began research to develop catalytic converters for gasoline engines used on cars. He was awarded United States Patent 2,742,437 for his work.〔"(His Smoke Eating Cats Now Attack Traffic Smog )". ''Popular Science'', June 1955, pp. 83-85/244.〕 Widespread adoption of catalytic converters did not occur until more stringent emission control regulations forced the removal of the anti-knock agent tetraethyl lead from most types of gasoline. Lead is a "catalyst poison" and would effectively disable a catalytic converter by forming a coating on the catalyst's surface.〔Staff writer (undated). ("Eugene Houdry" ). Chemical Heritage Foundation. Retrieved 7 January 2011.〕 Catalytic converters were further developed by a series of engineers including John J. Mooney and Carl D. Keith at the Engelhard Corporation,〔 ("Carl D. Keith, a Father of the Catalytic Converter, Dies at 88" ). ''The New York Times''. 15 November 2008.〕 creating the first production catalytic converter in 1973.〔 Staff writer (undated). "(Engelhard Corporation )". referenceforbusiness.com. Retrieved 7 January 2011.〕 William C. Pfefferle developed a catalytic combustor for gas turbines in the early 1970s, allowing combustion without significant formation of nitrogen oxides and carbon monoxide.〔Robert N. Carter, Lance L. Smith, Hasan Karim, Marco Castaldi, Shah Etemad, George Muench, R. Samuel Boorse, Paul Menacherry and William C. Pfefferle (1998). "(Catalytic Combustion Technology Development for Gas Turbine Engine Applications )". ''MRS Proceedings'', 549, 93 doi:10.1557/PROC-549-93〕〔Worthy, Sharon. "(Connecticut chemist receives award for cleaner air technology )". ''Bio-Medicine''. 23 June 2003. Retrieved 11 December 2012.〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Catalytic converter」の詳細全文を読む スポンサード リンク
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