Recent advances in sulfur-resistant DeNOx catalysts for stationary source emissions: A state-of-the-art review

Abstract

Selective catalytic reduction (SCR) has become the mainstream technology for industrial flue gas purification, widely adopted at stationary sources due to its high nitrogen oxides (NO_x) removal efficiency, environmental friendliness, and proven reliability. However, the presence of SO₂ in flue gas leads to catalyst poisoning and deactivation, posing a major challenge to the system's core components. Therefore, understanding sulfur-induced deactivation mechanisms and developing sulfur-resistant strategies are critical for optimizing SCR systems, with significant theoretical and practical implications. This review systematically examines recent advances in the understanding of sulfur poisoning mechanisms, sulfur-resistant design strategies, and regeneration technologies for SCR catalysts. Distinct deactivation mechanisms have been identified across various non-precious metal-based catalysts, such as V, Mn, Ce, Cu, and Fe. Subsequently, sulfur-resistance strategies — including element doping, bimetallic synergy, support optimization, morphological engineering, and operational parameter adjustment — are comprehensively discussed. Moreover, regeneration methods for sulfur-poisoned catalysts are systematically evaluated, considering both cost-effectiveness and environmental sustainability. Finally, the design strategies and future challenges for the development of sulfur-resistant deNO_x catalysts are highlighted, aiming to guide their practical application in real-world flue gas purification systems.