CuCe-SAPO-34选择性催化丙烯还原柴油车尾气氮氧化物
Selective catalytic reduction of nitric oxide with propylene over CuCe-SAPO-34 catalysts under diesel engine exhaust
周皞 1王旭瑞 1赵辉爽 1温妮妮 2苏亚欣2
作者信息
- 1. 常州工程职业技术学院,江苏 常州 213164
- 2. 东华大学环境科学与工程学院,上海 201620
- 折叠
摘要
采用等体积浸渍法制备CuCe-SAPO-44分子筛催化剂,用于选择性催化丙烯还原柴油车尾气氮氧化物(C3H6-SCR).采用X射线衍射(XRD)、N2吸附-脱附、紫外可见光谱(UV-Vis)、H2程序升温还原(H2-TPR)和NH3程序升温脱附(NH3-TPD)等方法对催化剂的物理化学性质进行表征.研究表明,引入的铈与铜物种之间存在相互作用,有利于生成更多的孤立Cu2+物种,提高了分子筛催化剂的低温氧化还原性能,从而提高了CuCe-SAPO-34的低温脱硝活性.同时,双金属分子筛骨架上具有丰富的Lewis酸性位,有助于C3H6和NOx的吸附和活化.当Cu∶Ce=4∶2时,CuCe-SAPO-34催化剂具有最佳的脱硝性能,在含有10%O2和5%H2O的柴油车尾气氛围中,在250℃最高能实现90%以上的脱硝效率.
Abstract
CuCe-SAPO-44 zeolite catalysts were prepared by incipient wet impregnation method,and their activities of selective catalytic reduction of nitric oxide with propylene(C3H6-SCR)were investigated under lean burning condition.These catalysts were characterized by X-ray diffraction(XRD),N2 adsorption-desorption,UV-vis spectroscopy(UV-Vis),H2 temperature-programmed reduction(H2-TPR)and NH3 temperature-programmed desorption(NH3-TPD).The results had shown that the interaction between the introduced cerium and copper species was beneficial for generating more isolated Cu2+species which improved the low-temperature redox performance of the CuCe-SAPO-34 zeolite catalysts,and thus enhanced the low-temperature SCR activity.There were abundant Lewis acid sites on the skeleton of the bimetallic zeolite catalysts,which were favorable for the adsorption and activation of NOx and C3H6.When Cu∶Ce=4∶2,CuCe-SAPO-34 exhibited the best de-NOx activity with a conversion of NOx more than at 90%when the diesel engine exhaust contained 10%O2 and 5%H2O at 250℃.
关键词
分子筛催化剂/铈/选择催化还原/氮氧化物/丙烯Key words
zeolite catalysts/cerium/selective catalytic reduction/nitrogen oxide/propylene引用本文复制引用
基金项目
国家自然科学基金(52276103)
江苏省高等学校优秀科技创新团队项目(2019)()
出版年
2024
国家科技期刊平台
NSTL
万方数据