Recent advances in simultaneous removal of SO2 and NOx from exhaust gases: Removal process, mechanism and kinetics

SO2 and NOx, major gaseous pollutants in exhaust gas, can exert adverse effects on human health and environmental disaster. Therefore, numerous desulfurization (de-SO2) and denitrification (de-NOx) technologies have been designed to reduce SO2 and NOx emissions. Compared to traditional multi-step removal processes, simultaneous removal of SO2 and NOx has been attracting significant attention recently. This paper timely reviewed available literature focused on simultaneous de-SO2 and de-NOx methods, which are classified into four pathways as oxidation, reduction, adsorption/absorption and microbial purification. The removal process, basic mechanism and kinetics of each pathway are systematically reviewed in consideration of reactants, catalyzers, temperatures and atmosphere. Moreover, the main challenges and potential breakthroughs in developing novel simultaneous de-SO2 and de-NOx methods are critically discussed to provide a roadmap for prospective research activities. Therefore, this review provides a deeper insight in understanding the mechanisms of de-SO2 and de-NOx, and then helps to develop innovative simultaneous removal methods or improve the efficiency of available abatement methods.

Automated summary

The paper provides a timely review of simultaneous de-SO2 and de-NOx methods, categorizing them into four pathways and systematically reviewing the removal process, basic mechanism, and kinetics of each pathway. The main challenges and potential breakthroughs in developing novel methods are critically discussed, providing a roadmap for prospective research activities. This review offers deeper insights into understanding the mechanisms of de-SO2 and de-NOx, aiming to develop innovative simultaneous removal methods or enhance the efficiency of available abatement methods.