Preparation And Properties Of Fe-Mn Based Catalysts For The Low-temperature Selective Catalytic Reduction Of Nitrogen Oxides

Nitrogen oxides (NOX) are the main pollutants of the atmosphere. The main sources of NOX are the emissions from industrial coal burning and automobiles. The Selective Catalytic Reduction (SCR) technology is currently one of the most effective methods to remove NOx from the emission gases. To cut down the cost and match domestic boilers conveniently, efficient low temperature catalysts are greatly needed. Based on recent research, Mn-based catalysts were found to have advantages of low temperature activity and resistance to deactivation; on the other hand, Fe-based catalysts are of low price and easy to be produced, and have other applicability advantages, which have a wide application prospect. In this paper, Fe-Mn-based SCR catalysts were prepared and studied.Using Fe-Mn metal as the active component, oxide catalysts were prepared using the citric acid method, and the supported molecular sieve catalysts were prepared by the co-precipitation method, separately. This work investigated the catalyst activity of the Selective Catalytic Reduction of NOx at different reaction temperatures. NH3was used as the reducing agent and the reaction was conducted in an oxygen-rich environment. The paper also describes the influence of different active components and their contents to their catalytic activity. X-ray Diffraction (XRD) and Brunauer Emmett Teller (BET) were used to study the properties of the catalyst. The results show that the mixture of these two metals can greatly improve the low-temperature activity of NOx. Moreover, the NOx conversion rate of the Fe (0.3)-MnOx mixed oxide catalysts reached90%at the temperature of100℃. Meanwhile, the Fe-Mn (Fe/Mn=1:1) modified H-ZSM-5catalysts also had better NOx conversion rate at low temperature, and it reached more than90%at180℃.