Introduction: General Description A catalytic converter is an exhaust component used in modern automobiles to reduce the emission of toxic gases. The average catalytic converter is capable of converting approximately 98% of these harmful emissions into relatively benign byproducts (UC Davis). It does this through the use of a catalyzing agent, which, combined with heat and oxygen, produces a chemical reaction capable of converting various gases such as carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxides (NOx) into less harmful carbon dioxide (CO2), nitrogen (N2) and water (H2O) (Wiki). The catalytic converter was first introduced in the mid-1970s, but did not see widespread adoption until new emissions regulations mandated the removal of gasoline's "tetraethyl lead" fuel additive. This is because the combustion of tetraethyl lead in an internal combustion engine produced toxic byproducts capable of neutralizing the catalytic agents in the catalytic converter rendering it ineffective (Wiki). Catalytic converters are divided into two basic types: two-way and three-way. The bidirectional catalytic converter exclusively performs the oxidation reaction (addition of oxygen), converting carbon monoxide to carbon dioxide and converting hydrocarbons to carbon dioxide and water. In contrast, the three-way catalytic converter not only performs the oxidation reaction but also performs a reduction reaction (the removal of oxygen), converting nitrogen oxides (such as nitrogen oxide, nitrogen dioxide, and nitric oxide) into nitrogen and oxygen (SmogTips). The two-way catalytic converter was quite common, we are talking about 1981, when the three-way catalytic converter replaced it in most automotive applications (Wiki)....... middle of paper...... 2CarPros 2011. Web. November 6, 2011 “Using Platinum and Palladium: Close-up Image of Catalytic Converter” buy-palladium.blogspot.com Buy Palladium March 6, 2009. Web. November 6, 2011“Products” logicotradingco.com.Logical Trading Company 2011. Web. 6 November 2011 "Three-way catalytic conversion (TWC) systems" diagram. Logicaltradingco.com.Logical TradingCompany 2011, November 6, 2011 Woodford, Chris “Catalytic Converters” explainsquellostuff.com Explain It Suff! August 12, 2011.Web. 6 November 2011'Schematic diagram of three-way catalytic converter' Diagram openlearn.open.ac.uk< http://openlearn.open.ac.uk/mod/oucontent/view.php?id=398548§ion=1.2.1>