Automotive emission

The main areas of commercial apphcation are automotive emission control catalysts (autocatalysts), oil refining, ammonia oxidation, hquid-phase ... 

Automotive Emission Control Catalysts. Air pollution (qv) problems caused by automotive exhaust emissions have been met in part by automotive emission control catalysts (autocatalysts) containing PGMs. In the United States, all new cars have been requited to have autocatalyst systems since 1975. In 1995, systems were available for control of emissions from both petrol and diesel vehicles (see Exhaust control, automotive). 

E. Hamaim, H. Manger, and L. Stencke, Eambda Sensor with Y203—Stabilisyed Zr02—Ceramicfor Application in Automotive Emission Control Systems,... 

Calculations that are repeatedly made can be made more accurately, and at lower cost, by using a computer. If, for example, automotive emissions are continually tested over a standardized driving cycle, a computer program to analyze the data is a necessity. Otherwise, days would be spent calculating the data obtained in hours. 

As initially discussed in Section 3, carbon canisters are used in the automotive emission control system to temporarily store hydrocarbon vapors. The vapors are later purged into the air charge stream of the air induction system, thus regenerating the carbon canister. Carbon canister design is dependent on the characteristics of the vapors sent to the canister and the amount of purge air available. In the following section, factors that affect the performance of the evaporative emission control system will be discussed. 

A catalytic oxidation system may cost 150 per car, but the catalyst cost is estimated to be 30, less than 1% of the cost of an automobile (2). In a few years, the gross sale of automotive catalysts in dollars may exceed the combined sale of catalysts to the chemical and petroleum industries (3). On the other hand, if the emission laws are relaxed or if the automotive engineers succeed in developing a more economical and reliable non-catalytic solution to emission control, automotive catalysis may turn out to be a short boom. Automotive catalysis is still in its infancy, with tremendous potential for improvement. The innovations of catalytic scientists and engineers in the future will determine whether catalysis is the long term solution to automotive emissions. 

The catalyst companies were encouraged to resume their research activities in automotive catalysis in the late 1960 s as further tightening of automotive emissions standards became imminent, and it appeared that mere engine modifications might be inadequate to meet the new standards. A systems approach was first used upon the formation of the Inter-Industry Emission Control Program by the Ford Motor Company and the Mobil Oil Corporation in 1967, which was joined by a number of oil companies in the U.S. and a number of automobile companies in Italy, Japan, and Western Germany. 

In the 20 years since the Brunddand report, great developments have taken place in industries toward sustainable practices. As a case in point, the problem of acid rain, an issue of concern in 1987, has improved to a large extent, thanks to catalytic pollution abatement both in stationary and automotive emissions. Catalysis for Green Chemistry and Engineering will continue to have a cracial role in improving the environmental performance of industry [25-27]. Nowadays, catalytic procedures are often implemented according to the green chemistry... 

Halogenated phenols, particularly 2-bromo-, 2,4-dibromo-, and 2,4,6-tribromophenol, have been identified in automotive emissions and are the products of thermal reactions involving the dibromoethane fuel additive (Muller and Buser 1986). It could therefore no longer be assumed that such compounds are exclusively the products of biosynthesis by marine algae. 

Muller MD, H-R Buser (1986) Halogenated aromatic compounds in automotive emissions from leaded gasoline additives. Environ Sci Technol 20 1151-1157. 

Nishibata, Y., Mizuki, J., Akao, T. et al. (2002) Self-regeneration of a Pd-perovskite catalyst for automotive emissions control, Nature 418, 164. 

Ward, N.I. and R.R. Brooks. 1979. Lead levels in wool as an indication of lead in blood of sheep exposed to automotive emissions. Bull. Environ. Contam. Toxicol. 21 403-408. 

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... 

Emissions control. See also Automotive emission control Industrial emission control... 

Federal Reserve Act, 12 683 Federal Test Procedure (FTP), automotive emission, 10 33-35... 

Testing, see also Nondestructive evaluation (NDE) Plastics testing automotive emission, 10 31-35 drug, 21 573-574 of dyes, 9 230-234... 

Eu O consumed, totaling 6-7 tons in the U.S., is used for phos-phor manufacture—80% to 90% of this for CRT s, the remainder for lighting. About 2/3 of the Y O consumed ( v 100 tons U.S.) is used for phosphors. This fraction might decrease if some other envisioned uses for yttria-based ceramics, e.g., automotive emission sensors, reach fruition. 

As lead in automotive emissions has been found largely in the fine particle fraction (22, 23), it is reasonable to expect a similar size distribution pattern for manganese from automotive sources. This would explain the strong association between MN and PB in the factor analyses reported here. This probably also explains the association of MN (TSP samples) with several factors at low loadings, rather than with a single factor as the TSP samples would include the mass of respirable as well as coarse manganese. When the concentration of the tracers in coarse particles (calculated as the differences in concentration between the TSP and RSP samples) were included with the RSP data for factor analysis, a factor on which 20% of the total variance (No. 5, Table I) was loaded was obtained. 

Based on these results and considerations, it was concluded that Pb, V, Cu and SO. could be used as source tracers for automotive sources, oil-burning, incineration and secondary (or sulfate-associated) sources, respectively. Mn, however, should probably be considered as a composite tracer of automotive emissions and soil-related sources (resuspension of dust). 

It should be noted that Pb concentrations in this polluted air are about 100 times lower than the aerosol S levels, or are only a few tens of ng Pb/m. In the Beijing area the contribution of automotive emissions to atmospheric Pb at Xinglong is expected to be minor owing to the small amounts of leaded gasoline used privately owned automobiles, trucks, and other gasoline powered vehicles are nonexistent in China. Instead, coal combustion may be the principal source of fine particle Pb as well as K and S. 

Mehrdad Ahmadinejad, Maya R. Desai, Timothy C. Watling and Andrew P.E. York, Simulation of Automotive Emission Control Systems... 

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