Research on the resistance of catalysts for selective catalytic reduction: Current progresses and future perspectives

Abstract

SCR (Selective Catalytic Reduction) catalysts are used in a variety of industrial applications to reduce nitrogen oxide (NOx) emissions from exhaust gases. SCR catalysts can be poisoned by contaminants in the exhaust gas, such as sulfur, phosphorus, and alkali metals. These poisoning leads to deactivation of catalysts and thus need to be avoided. The objective of this review is to provide a comprehensive and systematic overview of the mechanisms of poisoning and the research on resistance of various metal oxide catalysts, including vanadium-based, cerium-based, copper-based, manganese-based, and iron-based catalysts, as well as various zeolite catalysts. The discussion will cover the catalysts' resistance against hydrothermal aging, sulfur poisoning, phosphorus poisoning, alkali metal poisoning, alkaline earth metal poisoning, and heavy metal poisoning. Furthermore, potential approaches and strategies for enhancing catalyst resistance in the future will also be examined. The article serves as a valuable resource for researchers and practitioners working on SCR technology and emissions control, providing insights into the mechanisms of catalyst poisoning and strategies for improving catalyst resistance.