Automotive emissions, regulation

CONCAWE Report N 10/77 "Automotive emission regulations and their impact on refinery operations". 

Automotive emission control, 10 30-67 for alternative fuels, 10 59-60 alternative systems, 10 58-59 catalytic converter chemical reactions and surface chemistry, 10 46—50 catalytic converter design, 10 39—46 diesel engine, 10 60-62 emission control system, 10 38-39 emission regulation and testing, 10 31-35... 

The 2007 federal law comes after the State of California adopted stiff regulations on its own in September 2004. The California Air Resources Board voted unanimously to adopt regulations to improve average fuel economy by as much as 40% by 2016. Moreover, the state adopted greenhouse gas regulations that require a major reduction of automotive emissions. California standards have a decided impact on manufacturers since that state accounts for 10% of all new auto sales in the U.S. 

New regulations in the United States and Europe mandate that automotive emissions must decrease substantially from current levels. As a result, there is a strong incentive to develop improved TWC with better oxidation activity at low temperatures since most of the hydrocarbons and CO are emitted immediately following cold starts of engines. As previously mentioned, the addition of transition metal oxides can have a beneficial effect on the performance of Au catalysts in CO oxidation. Combinations of Pt or Pd with transition metal oxides are also active in CO oxidation at low temperatures 50). Figure 11 shows examples of the reaction over Pt/MO/ Si02 catalysts. 

TABLE 3.2 Typical Automotive Emissions Before and After Regulation, Related to U.S. Legislated Standards"... 

High-solids (HS) coatings are increasing rapidly in Importance (as previously discussed) because of their compatibility with existing application equipment and their ability to meet many emission regulations. Automotive and appliance applications for these systems should continue to grow well in the 1980s. 

G.J. Barnes and R.J. Donohue, A Manufacturers s View of World Emissions Regulations and the Need for Harmonization of Procedures, Society of Automotive Engineers Paper No. 850391 (February, 1985). 

Since 1975, CATALYSIS has been the only practical way for automotive manufacturers to meet the severe regulation of exhaust gas emission in JAPAN and in the U.S. Similar measures will be applied in Europe in the near future. For numerous economic and technical reasons, automotive emission control catalysts are supported catalysts. This means that the active phase is dispersed on the surface of a catalytically almost inert material. That material is the subject of this investigation. 

Model development started with analysis of the behavior of the real price of platinum overtime. The nominal price was deflated by the consumer price index. Preliminary analysis indicates that the mean real price may be constant over a 100 year span however, statistical tests are being performed to validate this result (see Figure 5). Excursions from the mean real price can be accounted for by specific events, for example, World War I and the U.S. regulations on automotive emissions. However, over time, the supply and demand come back into balance through increases in production or substitution of non-PGM materials. 

Ce02-Zr02 has been an essential material of three-way catalysts for automotive emission control under the recent regulation. Because the redox behaviour of Ce02 was improved by the formation of Ce02-Zr02 solid solution derived from... 

Cerium-zirconium mixed metal oxides are used in conjunction with platinum group metals to reduce and eliminate pollutants in automotive emissions control catalyst systems. The ceria-zirconia promoter materials regulate the partial pressure of oxygen near the catalyst surface, thereby facilitating catalytic oxidation and reduction of gas phase pollutants. However, ceria-zirconia is particularly susceptible to chemical and physical deactivation through sulfur dioxide adsorption. The interaction of sulfur dioxide with ceria-zirconia model catalysts has been studied with Auger spectroscopy to develop fundamental information regarding the sulfur dioxide deactivation mechanism. 

The present three-way catalyst (TWC) consists of the noble metals Pt or Pd and Rh, with Rh being the most efficient catalyst for NO reduction to N2 (1, 2). At low temperatures, the overall NO conversion over Pt is better than over Rh (3, 4). However, the selectivity of Pt to N2 formation is poor. In the next years new regulations in the USA and Europe mandate that automotive emission must fall... 

Recent amendments to the Clean Air Act have set up more stringent requirements for automotive emissions. By 2009, all vehicles will be required to adhere to the Federal tier 2 standards. The EPA regulations cover California emission categories in order to make certification to the federal and California standards easier for vehicle manufacturers. Many states are adopting the California standards to meet the more stringent regulations. 

More recently oxygenated fuel components have been found to have a beneficial effect on air quality. As public interest in environmental issues has grown, legislators and regulators are seeking various routes to improve air quality. As will be shown later, oxygenates could play a role in lowering automotive emissions. 

Gasoline composition may also be regulated in Europe. A tripartite initiative is being carried out among the European Commission, the oil industry, and the automotive industry. Based on an analysis of the required improvements in air quaUty, new regulations are to be written that control vehicle emissions and fuel composition into the twenty-first century. 

J. Lautikko and N-O. Nyland, Regulated and Unregulated Emissionsfrom Catalyst Vehicles atEow Ambient Temperatures, SAE 930946, Society of Automotive Engineers, Warrendale, Pa., 1993. Good reference for low ambient temperature emissions. 

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