摘要
为了改善L型沸石的催化性能,优化其在FCC中的应用,对L沸石进行离子交换和脱铝的改性研究。考察离子交换时间和离子交换方式对降低L沸石中氧化钾含量的影响及水热焙烧和化学脱铝对提高L沸石硅铝物质的量比的影响。结果表明,L型沸石离子交换时间不易过长,较适宜的时间为3 h。离子交换和水蒸汽处理相结合对降低L型沸石的钾含量更有效,离子交换和水蒸汽处理交替进行3次的样品氧化钾质量分数可降至0.82%。水热焙烧和化学脱铝能使L型沸石显著脱铝,其中,经过700℃水蒸汽处理1 h,再进行盐酸处理而制得改性L型沸石样品的硅铝物质的量比可达21.91,相对结晶度高于80%。
L zeolite was modified by ion exchange and dealumination for improvement on its FCC behaviors. The influence of ion exchange time and ways on the reduction of K2O content in L zeolite and the influence of dealumination by hydrothermal and chemical methods on the increase in silica/alumina molar ratio were investigated. The results showed that the appropriate ion exchange time was 3 h. Combination of ion exchange and hydrothermal method was more effective to reduction of K2O content in L zeolite. K2O content in the zeolite modified by the combined method 3 times was reduced to 0.82%. L zeolite could be remarkably dealuminated by hydrothermal and chemical methods. Silica/alumina molar ratio of 21.91 was attained after hydrothermal treatment under 700℃ for 1 h followed by hydrochloric acid treatment, with relative erystallinity of over 80%.
出处
《工业催化》
CAS
2008年第9期41-45,共5页
Industrial Catalysis
关键词
催化化学
L型沸石改性
离子交换
焙烧
脱铝
氧化钾含量
catalytic chemistry
L Zeolite modification
ion exchange
calcination
dealuminization
potassium oxide content
作者简介
陈宜俍 ,1953年生,女,河北省保定市人,教授,硕士生导师,主要研究方向为催化新材料分子筛制备。通讯联系人:陈宜恨。E—mail:liangchen@zzu.edu.cn