Performance of monolithic Mn catalyst for low temperature SCR

Abstract

Abstract: Monolithic Mn catalysts were prepared by two different Mn precursors (manganese nitrate and manganese acetate), and these catalysts were characterized by BET, XRD, XPS and NH₃-SCR.The catalyst prepared by manganese nitrate has higher low-temperature de NO_x activity than that prepared by manganese acetate.The de NO_x efficiency of MnN/TiO₂/CC catalyst was close to 100% in the reaction temperature between 150℃ and 250℃. However, when the reaction temperature was above 250℃, the activity of MnA/TiO₂/CC catalyst was better than MnN/TiO₂/CC catalyst.Characterization results showed that higher surface Mn concentration and weak acids were found on MnN/TiO₂/CC catalyst.

Key words: low temperature, deNO_x, cordierite ceramic honeycomb, manganese

摘要： 采样硝酸锰和乙酸锰两种Mn的前体制备以堇青石为基体的整体式脱硝催化剂,并进行了氨选择性催化还原NO反应(NH₃-SCR)和BET、XRD、XPS等表征。以硝酸锰为前体的催化剂具有更好的低温脱硝活性,在反应温度150～250℃的范围内,MnN/TiO₂/CC催化剂的脱硝率接近100%;而当反应温度超过250℃后,MnA/TiO₂/CC催化剂比MnN/TiO₂/CC催化剂具有更高的脱硝活性。表面Mn活性位和弱酸位多是MnN/TiO₂/CC催化剂低温SCR活性好的主要原因。

关键词: 低温, 脱硝, 堇青石蜂窝陶瓷基体, 锰

WANG Xuehai, WU Hao, LIU Zhongsheng. Performance of monolithic Mn catalyst for low temperature SCR[J]. Chemical Industry and Engineering Progree, 2015, 34(s1): 127-130.

王学海, 吴昊, 刘忠生. 整体式Mn基低温脱硝催化剂研究[J]. 化工进展, 2015, 34(s1): 127-130.

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