Cu-SAPO-34/堇青石的原位制备及其催化丙烷还原柴油机车尾气中NO_x  

In Situ Synthesis of Cu-SAPO-34/Cordierite for the Catalytic Removal of NO_x From Diesel Vehicles by C_3H_8

作　　者：刘致强[1] 唐磊[1] 常丽萍[1] 王建成[1] 鲍卫仁[1] 

机构地区：[1]太原理工大学煤科学与技术教育部和山西省重点实验室,山西太原030024

出　　处：《催化学报》2011年第4期546-554,共9页

基　　金：国家自然科学基金(20906067);山西省科技基础条件平台建设项目(2010091015)~~

摘　　要：采用原位水热法制备了Cu-SAPO-34/堇青石整体式催化剂,运用X射线衍射、扫描电镜和N2吸附-脱附等技术对其进行了表征,并在固定床反应器上评价了其催化丙烷还原模拟柴油机车尾气中NOx性能,考察了丙烷和O2浓度以及水蒸气对催化剂性能的影响.结果表明,所制整体式催化剂中Cu-SAPO-34涂层与载体结合牢固紧密,经一次操作Cu-SAPO-34负载量大于20%,且其比表面积较载体显著增加.另外,Cu的加入能显著提高催化剂上丙烷选择性催化还原NOx的活性,在500～650°CNOx浓度可降低60%以上.当原料气中添加10%水蒸气后,NOx转化率有所降低,但停加水蒸气后,催化剂活性可部分恢复.A Cu-SAPO-34/cordierite catalyst was prepared by in situ hydrothermal synthesis.The morphology and structure of the Cu-SAPO-34/cordierite samples were characterized by X-ray diffraction,scanning electron microscopy,and physical adsorption-desorption analyzer.The removal of NOx from simulated diesel vehicle exhaust gas was carried out using a fixed-bed reactor.The effects of C3H8,O2 concentrations,and water vapor on the activity of the catalyst were studied.The results indicate that the Cu-SAPO-34 coatings obtained by the in situ synthesis are firm and compact,and the loading amount is found to be more than 20% after one synthesis operation.The surface areas of the Cu-SAPO-34/cordierite catalysts increase greatly compared with that of cordierite.The active Cu component prepared through in situ synthesis can significantly improve the activity of selective catalytic reduction of NOx by C3H8.NOx reduction over the Cu-SAPO-34/cordierite catalyst is more than 60% between 500 and 650 °C.The NOx conversion decreases after the addition of 10% water vapor to the feed gas but the deactivation caused by water vapor is not permanent.

关 键 词：铜 SAPO-34分子筛 堇青石 氮氧化物 丙烷 原位合成 选择性催化还原 柴油机 

分 类 号：X701[环境科学与工程—环境工程]