This book describes the impact of synthetic material as a catalytic convertor in Diesel engine Emission Reduction. In this work, Kevlar Composite material is tested and evaluated for a reduction in NOx values and other components of exhaust gas from an IC engine. Kevlar composite material has been prepared using epoxy resin and cut into circular shapes of required diameters with holes in it. Variations in testing were tried with the number of Kevlar pieces, i.e., 4, 6, 8, 10 inside the catalytic converter. VCR Engine has been used for the testing purpose and the fuel used is biodiesel, which is a blend of lemongrass oil and diesel of fixed proportions. The result successfully showed a significant reduction in NOx values with a maximum reduction in the test that had 10 Kevlar pieces. The values were compared with that of diesel and graphs of BTE, SFC, NOx and other components were plotted against BMEP.