Overview of the Generation Mechanism, Influence Factors, and Control Technologies of NH₃ Emissions from Road Transport Vehicles

NH₃ is a toxic gas that poses a significant threat to both the atmospheric environment and human health. In the transportation sector, NH₃ emissions from road mobile sources, mainly consisting of gasoline vehicles, diesel vehicles, and natural gas vehicles, have become the primary source of NH₃ in the air. Increasingly strict emission regulations have been implemented worldwide. Based on this, this article meticulously analyzes the causes of NH₃ emissions. It systematically expounds on the NH₃ emission characteristics of these three major types of road vehicles under various complex dynamic driving conditions and carefully sorts out the numerous and intricate influencing factors behind them, clarifying the internal logic and mechanisms of NH₃ emissions from road vehicles. In addition, this paper also reviews the latest cutting-edge research on various types of catalysts within the Ammonia Slip Catalyst (ASC) used for controlling vehicle NH₃ emissions and discusses the technical routes for improving the performance of ASC catalysts. Finally, this paper puts forward many ideas and insights for future research trends of NH₃ emissions from road vehicles and ASC technology. This work is committed to the reduction of NH₃ emissions on a global scale.