铁矿石SCR低温脱硝催化剂的改性研究

Study on Modification of Iron Ore Catalysts for Low-temperature SCR Denitrification

将稀土元素Ce掺杂进菱铁矿制备改性催化剂,采用该催化剂进行烟气SCR低温脱硝反应,研究其催化活性,并利用X-荧光分析法(XRF)、比表面积分析法(BET)、X-射线衍射法(XRD)、NH_3-程序升温脱附法(NH_3-TPD)等对改性前后的菱铁矿催化剂进行表征分析.结果表明:改性后菱铁矿催化剂的催化活性有显著提高,抗硫性和持久性也有较大提高;菱铁矿掺杂Ce后,原菱铁矿中Fe、Mn等元素与Ce元素相互作用,致使比表面积增大,晶型结构得到改善,表面酸性有所提高,从而大大提高了催化活性.

Siderite particles were modified by mixing with rare earth element Ce to prepare SCR catalysts, and subsequently low-temperature SCR flue gas denitrification was conducted to study the activity of the catalysts. Meanwhile, the siderite catalysts were characterized by XRF, BET, XRD and NH3-TPD analy- sis before and after modification. Results show that the catalytic activity of modified siderite catalysts is significantly improved, and their sulfur resistance and durability are promoted accordingly. After doping with Ce, elements Fe and Mn in original iron ore would react with Ce, which makes the specific surface be enlarged, the crystal structure be improved and the surface acidity be increased, resulting in enhanced ac- tivity of the modified catalysts.