Synthesis of stable cerium zirconium oxide nanoparticle – Diesel suspension and investigation of its effects on diesel properties and smoke

Abstract

One of the main problems of diesel engines is the harmful smoke in exhaust and the use of fuel borne catalysts is a good option for controlling the same. Cerium zirconium mixed oxide (CexZr(1−x)O2) nanoparticle is an excellent fuel borne catalyst. Two main issues with the addition of cerium zirconium mixed oxide nanoparticles in diesel are the lack of stability of catalytic nanoparticle in diesel suspension and the influence of these nanoparticles on various properties of diesel. The present work focuses on the synthesis of stable suspension of cerium zirconium mixed oxide nanoparticles in diesel and also on the effect of these nanoparticles on fuel properties, diesel engine performance and exhaust smoke. Cerium zirconium mixed oxide nanoparticle was synthesized by co precipitation method and characterized using Transmission electron microscope and Dynamic light scattering techniques. Catalytic activity of mixed oxide nanoparticles was compared by means of Temperature programmed reduction technique. Nanofluid was prepared by two step method, employing an ultrasonic shaker and oleic acid was used as surfactant to improve the stability of nanoparticle in diesel. The concentration of surfactant was varied from 0.01 to 0.1% by volume and the optimum value was determined by means of UV spectrum absorbance study. The dosing level of nanoparticles in diesel was varied from 2.5 to 20ppm and the optimum concentration of catalytic nanoparticles for maximum stability was determined based on zeta potential measurement. Various properties of diesel and modified diesel were determined as per ASTM standards. Load tests were carried out on a single cylinder four stroke diesel engine to investigate the effect of catalytic nanoparticles on diesel engine performance and smoke. Performance studies shows 31% reduction in exhaust smoke and 3% enhancement in brake thermal efficiency of diesel engine for a nanoparticle concentration of 17.5ppm.