La_(0.5)K_(0.5)Mn_(1-x)Fe_(x)O_(3)催化剂去除柴油机碳烟和NO的性能研究  

Removal of Soot and NO from Diesel Engine by La_(0.5)K_(0.5)Mn_(1-x)Fe_(x)O_(3)Catalysts

作　　者：张琛[1] 刘军恒[1] 谈秉乾 孙平[1] 嵇乾 Zhang Chen;Liu Junheng;Tan Bingqian;Sun Ping;Ji Qian(School of Automobile and Traf-fic Engineering,Jiangsu University,Zhenjiang 212013,China;Wuxi Henghe EP Co.,Ltd,Wuxi 214174,China)

机构地区：[1]江苏大学汽车与交通工程学院,江苏镇江212013 [2]无锡恒和环保科技有限公司,江苏无锡214174

出　　处：《中国稀土学报》2023年第2期279-286,共8页Journal of the Chinese Society of Rare Earths

基　　金：中国博士后科学基金项目(2020M672133)资助。

摘　　要：通过柠檬酸络合法制备催化剂LaMnO_(3)和La_(0.5)K_(0.5)Mn_(1-x)Fe_(x)O_(3)(x=0.125,0.33,0.5),在微型固定床反应器中测试催化剂去除柴油机碳烟和NO的性能,同时通过XRD,H_(2)-TPR,Soot-TPR等技术对钙钛矿催化剂微观结构进行分析。结果表明:部分钾铁离子进入钙钛矿晶格内部,导致镧锰钙钛矿形成晶格缺陷,提高了催化剂中氧空位的数量;部分K^(+)与Mn^(3+)生成活性较高的钾锰矿,改变了碳烟与催化剂的接触状态,降低了碳烟起燃温度。催化剂活性评价表明:La_(0.5)K_(0.5)Mn_(0.67)Fe_(0.33)O_(3)具有最佳催化活性,对碳烟和NO具有较好的去除效果,CO_(2)浓度峰值温度为357℃,CO_(2)的选择性高达99.9%,NO最大转化率为61.7%。The catalysts LaMnO_(3) and La_(0.5)K_(0.5)Mn_(1-x)Fe_(x)O_(3)(x=0.125,0.33,0.5)were prepared by citric acid complexation.The performance of the catalyst to remove soot and NO from diesel engine was tested in a fixed-bed micro-reactor.The microstructure of the perovskite catalyst was analyzed by XRD,H_(2)-TPR,Soot-TPR and other techniques at the same time.The results show that a part of potassium and iron ions enter the crystal lattice of perovskite,resulting in the formation of lattice defects of lanthanum and manganese perovskite,which increases the number of oxygen vacancies in the catalyst.Part of K^(+)and Mn^(3+)produce high activity of potassium manganese ore and change the contact state of soot and catalyst,which reduces the ignition temperature of soot.Evaluation of catalyst activity shows that La_(0.5)K_(0.5)Mn_(0.67)Fe_(0.33)O_(3) has the best removal effect on soot and NO by its best catalytic activity.The temperature peak of CO_(2) concentration is 357℃,CO_(2) has a selectivity of up to 99.9%and the maximum conversion rate of NO is 61.7%.

关 键 词：柴油机 氮氧化物 碳烟 镧锰钙钛矿 排放控制 

分 类 号：TK421.5[动力工程及工程热物理—动力机械及工程]