NOx conversion efficiency of an SCR system with V2O5-WO3/TiO2 catalyst and C2H5OH reductant: An experimental study

Abstract

Internal combustion engines (ICEs) have long been the dominant power source in the transportation sector due to their high power-to-weight ratio. However, their widespread use poses significant environmental challenges, primarily due to the emission of harmful gases. To mitigate these emissions, stringent regulations necessitate the development of advanced after-treatment systems. In this study, a SCR (Selective Catalytic Reduction) system integrated with a diesel engine was investigated using V2O5-WO3/TiO2 as the catalyst and C2H5OH as the reductant. Engine tests were conducted under three different load conditions -no load (0 kW), 2 kW, and 4 kW- within an exhaust temperature range of 150-240 °C. NOx conversion efficiency (ηNOx) was evaluated with respect to engine load and temperature variations. Additionally, catalyst characterization was performed using Energy-Dispersive X-ray Spectroscopy (EDS), Scanning Electron Microscopy (SEM), Brunauer-Emmett-Teller (BET), and X-ray Diffraction (XRD) analyses. The results indicate that increasing engine load and exhaust gas temperature enhances ηNOx, likely due to the higher hydrocarbon (HC) content in the exhaust at increased load levels and improved catalytic activity at elevated temperatures. The highest ηNOx of 93.28% was achieved at 4 kW and 240°C.

Keywords

• diesel engine
• emission
• nox
• selective catalytic reduction

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