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World over, emission legislations are becoming stringent day by day. India too, is on the road map for more tough emission legislations. 2/3 Wheeler legislations in India are being considered as the most stringent in the world, where as, Passenger Car and light/heavy duty legislations are reaching Euro III and Euro IV limits in the near future. The present paper describes the system concepts to be followed to reach the emission targets, specially for Euro III and Euro IV for passenger cars. That includes necessity for using more advanced engine technologies such as Turbo Charging with Intercooling, EGR (cooled), Electronically Controlled Direct Injection, Common Rail / Pump - Nozzle systems. The new catalyst technologies required and developed for these applications are described. These technologies not only require to offer efficient emission reduction under fresh conditions, but need to meet the targeted results after long aging of over 80,000 km. The paper is divided in two parts.

World over, emission legislations are becoming stringent day by day. India too, is on the road map for more tough emission legislations. 2/3 Wheeler legislations in India are being considered as the most stringent in the world, where as, Passenger Car and light/heavy duty legislations are reaching Euro III and Euro IV limits in the near future. The present paper describes the system concepts to be followed to reach the emission targets, specially for Euro III and Euro IV for passenger cars. That includes necessity for using more advanced engine technologies such as Turbo Charging with Intercooling, EGR (cooled), Electronically Controlled Direct Injection, Common Rail / Pump - Nozzle systems. The new catalyst technologies required and developed for these applications are described. These technologies not only require to offer efficient emission reduction under fresh conditions, but need to meet the targeted results after long aging of over 80,000 km. The paper is divided in two parts.

1 In recent years Diesel DeNOx catalysts using additional hydrocarbons as reducing agents have been the focus of exhaust aftertreatment. The NOx reduction potential was often limited to 20 - 30 % in the European MVEG-A or the US FTP cycle by just adding a DeNOx catalyst on a vehicle. This result is explained by the fact that the catalyst was treated as a separate item and that the emission reduction strategy was not developed in a system approach. This paper summarizes results regarding the potential of state of the art Diesel DeNOx catalysts fitted to passenger cars and trucks when the exhaust gas system is optimized as a whole. The easiest way for a system approach is the combination of DeNOx catalysts with different working temperatures for NOx reduction. This has been demonstrated by the usage of several base metal catalysts for heavy duty applications. For passenger cars Platinum containing catalysts are strongly favored.

The awareness concerning environmental issues and the economical need for fuel savings leads to the introduction of new, highly efficient Diesel engines for passenger cars. An engine with common rail injection system could meet this target and, with the help of an advanced diesel exhaust aftertreatment system also fulfilled the new legislative emission regulations. Besides the efficient oxidation of carbon monoxide (CO), hydrocarbons (HC) and diesel particulates, such a system also requires a moderate reduction efficiency for nitrogen oxides (NOx) under excess oxygen conditions. The present paper illustrates the further progress in catalytic NOx-reduction under excess of oxygen by hydrocarbon enrichment using the common rail injection system.

SOF and de-NOx catalysts are applied to heavy-duty diesel trucks which are regulated by European 13 mode or Japanese 13 mode cycles. Precious metal free catalysts can reduce SOF at low temperatures without increasing sulfates up to 670C. This catalyst shows little deterioration after 400 hours of high temperature engine aging. 32% PM and 47% SOF reduction is observed under 13 mode tests when the exhaust gas temperature exceeds 700C (ECE-13 mode). This precious metal free catalyst is suitable for diesel trucks, especially trucks with natural aspirating engine whose exhaust gas temperature is very high. De-NOx catalysts with a 300-500C NOx reduction temperature window are applied to the Japanese heavy-duty test cycle (Japan 13 mode). When secondary diesel fuel is added under modes 8 to 12, (secondary fuel addition only when catalyst inlet temperature is more than 300C), 19-25% NOx can be reduced with 2-4% fuel penalty.

Catalyst applications for gasoline and diesel engine powered passenger cars and 2-stroke Two- and Three-wheelers are the main focus of this paper. Catalyst durability and deactivating effects are discussed in detail. Experiences on Indian conditions are also included.

This paper traces the evolution of heavy-duty truck transmissions in Europe, comments on the factors that have influenced and will influence the designs, compares some of the types in current use, and gives the author's views on possible lines of further development in the next decade. The ultimate predominance of any particular truck transmission will, of course, be the result of compromise between legislative, economic, and geographic factors. All these influences vary considerably in their effects on European truck manufacture as compared to that in the United States. The discussion of these differences points up areas of interest to manufacturers of transmissions who engage in export of their products.