The use of biodiesel in a compression ignition (CI) engine has shown to be a promising alternative to conventional diesel owing to its ability to substantially reduce carbon and hydrocarbon emissions. However, an increase in the NOx due to the additional oxygen content from the fuel has led to different fuel pretreatment and exhaust gas after-treatment methods to curb emissions. Hydrogen peroxide (H2O2) has been recently investigated as an oxidant and emulsifier in biodiesel blends for CI engines. Although combustion improvement leading to reduced HC and CO emissions are reported, contrasting findings are found in the literature on the effect of NOx. Similarly, CeO2 nanoparticles have demonstrated its capability in NOx abatement and hence this paper aims to assess the combined effect of H2O2 concentration and CeO2 nanoparticles on the performance and exhaust emissions using B20 fuel. Three different concentrations of H2O2 (0.5%, 1%, and 1.5%) along with two levels of CeO2 nanoparticle concentrations (40, 80 ppm) are investigated. Maximum brake thermal efficiency (BTE) is observed at 75% load and 1.5% H2O2 concentration with an average improvement of 1.2% in BTE over neat B20. The average reduction in CO and HC emissions for 1.5% H2O2 emulsification over neat B20 is 56–60% and 41–48% respectively. For the H2O2 concentration of 0.5%, 1%, and 1.5%, the average decrease in NOx compared to B20 fuel is 5.6%, 16.1%, and 22.7% respectively. Increasing the nanoparticle concentration from 40 ppm to 80 ppm also decreases emissions and improves BTE but its impact is significantly lower compared to the effect of H2O2 emulsification. Increasing H2O2 concentration in fuel blend improves the micro explosions leading to better mixing of fuel and air promoting better combustion. This resulted in the reduction of CO, HC, and NOx emissions as H2O2 is an active carrier of O2 and •OH radicals which has a more dominant effect in improving combustion and reducing emissions.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)
- Fuel Technology
- Energy Engineering and Power Technology
- Organic Chemistry