Abstract:The excessive emission of carbon monoxide (CO) from steel sintering flue gas poses a significant threat to regional air quality and human health. This necessitates the development of effective CO treatment technologies for sintering flue gas. Among these, catalytic oxidation technology has emerged as a stable and efficient method for CO removal, leading to extensive research in this area. Noble metal-loaded catalysts, including those based on platinum (Pt), palladium (Pd), gold (Au), ruthenium (Ru), and iridium (Ir), are considered to have great application potential due to their excellent low-temperature oxidation performance and resistance to water and sulfur. However, challenges arise from the scarcity and high cost of noble metals, as well as the complex composition of flue gases. These factors complicate the application of noble metal-loaded catalysts in industrial settings, highlighting the importance of research focused on CO oxidation. Such studies are vital for reducing noble metal usage and enhancing the anti-poisoning performance of these catalysts. The activity of noble catalysts is primarily influenced by their physicochemical properties, including morphology, particle size, elemental doping, support type, oxygen vacancies, and surface hydroxyl groups. It has been observed that a moderate amount of H2O can enhance CO oxidation on these catalysts, while excessive H2O can inhibit the reaction due to competitive adsorption effects. Additionally, the presence of SO2 in the atmosphere can lead to its adsorption on noble metal active sites or carrier, further diminishing the adsorption efficiency of CO and O2 and causing carrier sulfation. The CO oxidation reaction on noble metal-loaded catalysts is governed by three mechanisms: Langmuir-Hinshelwood (L-H), Mars-van Krevelen (MvK), and Eley-Rideal (ER). H2O plays a dual role in these pathways, enhancing CO catalytic oxidation in some cases while inhibiting it in others. However, the presence of SO2 typically reduces the adsorption performance of CO and O2, which can lead to decreased catalyst activity or even deactivation. Given the emission characteristics of sintering flue gas, future research on noble metal-supported catalysts should focus on three aspects: (1) improving stability and anti-poisoning performance: Even after desulfurization, sintering flue gas contains residual SO2, necessitating catalysts that can withstand such conditions, (2) investigating activity in complex pollutant environments: Research should explore the activity of noble metal-based catalysts in the presence of various pollutants, including SO2, heavy metals, alkali metal dust, and chlorine-containing VOCs, and (3) reducing noble metal loading: Given the high flow rates of sintering flue gas, it is crucial to develop strategies that minimize noble metal usage while maintaining effective CO treatment. Close-