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Current work focuses on developing a non-noble metal-based Diesel Oxidation Catalyst (DOC) with high efficiency. In this work, 1% and 3% Zr supported on mesoporous CeO2-Al2O3 was prepared. The morphological, structural, and catalytic behavior of the synthesized catalyst was investigated through the BET surface area, SEM-EDX, XRD, and TGA. BET and XRD data revealed the catalyst’s mesoporous nature with a high surface area and low crystallinity. SEM images showed the porous nature of the catalyst’s surface, devoid of any agglomeration or sintering. EDX analysis further confirmed the elemental composition of the catalyst surface. TGA was used to study catalysts’ activity towards soot oxidation in loose contact mode. T50 observed for soot oxidation catalyzed over 1%, and 3% Zr/CeO2-Al2O3 was 263°C and 331°C, while for uncatalyzed soot, it was 400°C. The results conclude that the catalyst significantly enhanced soot oxidation.

Use of alternative fuels, and reduction of particulate and NOx emissions are major challenges for making diesel engines environmentally benign. Measures adopted for reducing gravimetric particulate emissions necessarily always do not reduce particulate number concentration, which is strongly related with adverse health effects. Current emission norms in some parts of the world limit particulate number concentration along with particulate mass. In this scenario, it becomes important to investigate effect of fuel injection parameters and fuel injection strategies such as pilot injections on particulate size-number distribution. A single cylinder research engine is used to evaluate the effect of different fuel injection strategies and injection timings (for pilot and main injections) on particulate size-number distribution and total particulate numbers.

Vegetable oils have energy content suitable to be used as compression ignition (CI) engine fuel. However, several operational and durability problems of using straight vegetable oils in CI engines are reported in the literature, which are primarily caused by their higher viscosity and low volatility compared to mineral diesel. The viscosity can be brought in acceptable range by (i) chemical process of transesterification, (ii) blending of oil with mineral diesel or (iii) by heating the vegetable oil using exhaust gas waste heat. Reduction of viscosity by blending or exhaust gas heating saves the chemical processing cost of transesterification. Present experimental investigations were carried out for evaluating combustion, performance and emission behavior of Jatropha oil blends in unheated conditions in a direct injection CI engine at different load and constant engine speed (1500 rpm).