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To achieve healthier and sustainable air quality and to protect human life, worldwide emission standards are being tightened for harmful vehicular air pollutants such as CO, hydrocarbon, NOx and particulate matters. Among selective catalytic reduction catalysts for NOx control in automotive after treatment system, Cu-SSZ-13 (Chabazite structure) is one of the most promising SCR catalyst, mainly used in light and heavy duty diesel vehicles. This article focuses on the development of Cu-SSZ-13 with desired properties such crystallinity, morphology, surface area and Cu loading in the catalyst. With the help of sophisticated catalyst characterization tools such as NH3-Temperature Programmed Desorption (TPD), Temperature Programmed Reduction (TPR), BET surface area, X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM), novel and highly active formulations of Cu-SSZ-13 are reported here.

Diesel engines are becoming popular because of more fuel efficient and durability. While the CO and HC impurities are significantly lower than in gasoline engines, the design strategies for reduction of Particulate Matter and Nitrogen Oxides remain a major challenge for environment. The work mainly focused on reduction of NOx from diesel engines using SCR technology under Indian driving conditions and furl availability. With BS III/IV fuel available in the country, the catalyst system of choices the Vanadia Tungsten Titania (VWT) system because of its proven resistance to Sulfur poisoning. However, under urban driving conditions on Indian roads, the major obstacle is the low engine out temperatures which are below the normal operating temperature window (200 to 450 °C) of VWT - SCR.

Diesel exhaust is typically at lower temperature compared to gasoline exhaust and would need a catalyst that has activity in low temperature range to be effective. Hence considerable research has been directed to improve low temperature activity of catalysts used in diesel application. One of the aspects that has been widely reported in literature is that small Pt clusters have a positive effect on reducing the CO light off temperature (LOT). To examine this phenomenon closely, the present work was taken up to correlate Pt cluster size with performance. Catalysts were prepared on various supports - Alumina, Siliceous clay, ceria-zirconia, etc with different metal loadings and the calcinations conditions were varied both in time and temperature as well as calcinations atmosphere. The cluster sizes were ascertained using Phillips Tecnai 20 Transmission Electron Microscope.

Small Commercial Vehicle (SCV) is an emerging Commercial Vehicle (CV) segment both in India and throughout the world. Vehicles in this segment have diesel engine of capacity less than 1 l and GVW of less than 3.5 t. Normally for the CV, engines are tested on engine dynamometer for emission test, but SCV are tested on chassis dynamometer as they are classified as N1.1 class vehicles. Hence SCV have to follow same emission regulations as diesel passenger cars. The main challenge is to meet BS-IV NOx and PM emission target together with high torque optimization along with required durability targets. This paper addresses this challenge and reports the work carried out on an Indian SCV with 0.7 l naturally aspirated indirect injection diesel engine.

Technologies for exhaust aftertreatment of diesel engines are driven by emission standards and Selective Catalytic Reduction (SCR) will play a key role in complying with the requirements, particularly for the heavy duty vehicles. Amongst the variety of catalysts for the SCR reaction, the Vanadium-Tungsten-Titanium-Based (VWT) system is preferred over the base metal doped zeolite because of the established advantages of wide temperature window, robust and durable performance and resistance to sulfur exposure. While the basic chemical reactions involved in ammonia-SCR are well known, the challenge lies in identifying the right combination of substrate and wash coat formulation to meet with customer specific requirements. An insight into the relevant materials properties of the substrates as well as the bulk surface properties of the wash coat such as its ammonia storage capacity, V2O5 dispersion and stability are important.

A computer based data acquisition and power control system has been designed and installed for conducting thermal test at 4M thermal vacuum chamber of ISRO Satellite Centre(ISAC), Bangalore, INDIA. The system consists of four main units viz. Temperature Signal Processing Unit(TSPU), Power and Control Unit(PACU), Spacecraft telemetry and thermal vacuum chamber facility data interface unit and Data Processing Unit(DPU). The system has capability of monitoring 512 thermocouple channels, 700 spacecraft telemetry thermal related parameters, facility parameters including chamber Vacuum level, chamber contamination level using Quartz Crystal Monitor data and 128 numbers of heat-flux/temperature control channels. TSPU and PACU are VME based system. DPU is based on Pentium processor with hot redundancy using Redundant Array Of Inexpensive Disks(RAID) to takeover in case of failure of a server. All the subsystem and their peripherals are networked using TCP/IP on Ethernet.