摘要
不使用任何有机模板剂,硝酸铜和正硅酸四乙酯(TEOS)经过酸性水解、碱性陈化和水热晶化,制备得到四配位铜修饰ZSM-5沸石(Cu-ZSM-5)。考察凝胶的Si/Al摩尔比、pH值、晶化温度和晶化时间对Cu-ZSM-5的晶型和相对结晶度的影响。采用X射线衍射(XRD)、红外光谱(FT-IR)、紫外漫反射谱和X-射线光电子能谱等手段对Cu-ZSM-5进行分析表征。结果表明:Cu-ZSM-5沸石具有MFI结构,结晶度高,无其他杂晶;铜原子以四配位为主。四配位铜是催化氧化苯乙烯的活性位点;在m(Cu-ZSM-5-50)=0.1 g、n(TBHP)/n(Styrene)=1.5、T=60℃、t=5 h条件下,苯乙烯转化率和苯甲醛选择性分别为76.5%和69.4%,表明Cu-ZSM-5-50具有较高的催化活性和较好的重复利用性。该制备方法不使用有机模板剂,无需高温焙烧,Cu-ZSM-5催化剂的制备成本大大降低。
Tetracoordinated copper modified ZSM-5 zeolite(Cu-ZSM-5)was prepared without any organic template by acid hydrolysis,alkaline aging,and hydrothermal crystallization of copper(II)nitrate and tetraethyl orthosilicate(TEOS).The effect of Si/Al molar ratio of gel,pH value,crystallization temperature and crystallization time on the crystal form and the relative crystallinity of Cu-ZSM-5 was investigated.Meantime,ZSM-5 was analyzed and characterized using X-ray diffraction(XRD),Fourier transform infrared(FT-IR)spectra,UV diffuse reflectance spectrum and X-ray photoelectron spectroscopy.The results show that Cu-ZSM-5 zeolite is characterized with MFI structure,high crystallinity and no other impurities.Copper atoms are mainly tetracoordinated.Tetracoordinated copper is an active site for catalytic oxidation of styrene.When meeting the following conditions:m(Cu-ZSM-5-50)=0.1 g,n(TBHP)/n(Styrene)=1.5,T=60℃,t=5 h,styrene conversion and Benzaldehyde selectivity are 76.5 and 69.4%,respectively,indicating that Cu-ZSM-5-50 has high catalytic activity and good reusability.This preparation method does not need organic templates or high-temperature roasting,thus greatly reducing the preparation cost of Cu-ZSM-5.
作者
刘献锋
张晨芳
张方
张东平
孔岩
LIU Xianfeng;ZHANG Chenfang;ZHANG Fang;ZHANG Dongping;KONG Yan(College of Environment Engineering,Nanjing Institute of Technology,Nanjing 211167,China;State Key Laboratory of Materials-Oriented Chemical Engineering,College of Chemical Engineering,Nanjing Tech University,Nanjing 210009,China;Geological Bureau of Jiangsu Province,Nanjing 210018,China)
出处
《石油学报（石油加工）》
EI
CAS
CSCD
北大核心
2024年第1期93-102,共10页
Acta Petrolei Sinica(Petroleum Processing Section)
基金
国家自然科学基金项目(21776129)
南京工程学院在职博士科研资助项目(ZJK202005)资助。
