摘要:The rising rate of pollution in urban areas has become a worldwide concern in recent years. Diesel engines are considered one of the largest contributors to environmental pollution caused by exhaust emissions, and they are responsible for several health problems as well. Diesel engines contain carbon monoxide, carbon dioxide, unburned hydrocarbons, and oxides of nitrogen. The reduction of Nitric oxides (NOx) emission from diesel engine exhaust is currently being researched by automotive manufacturers. After much research, selective catalytic reduction (SCR) technology was discovered to be effective in reducing nitrogen oxide emission from diesel engine exhaust. This paper is an attempt to explore the problems associated with the use of selective catalytic reduction (SCR) and compares selective catalytic reduction (SCR) with the latest technology named solid selective catalytic reduction (SSCR) for efficient reduction of NOx emission from the exhaust of diesel engines. The issue of contamination, malfunctioning, and freezing of diesel exhaust fluid (DEF) at low temperatures are the major problems associated with the application of SCR. It is observed that by controlling the quantity of ammonia slip, SSCR can give better performance in the reduction of NOx emission from the exhaust of diesel engines.