化工学报 ›› 2020, Vol. 71 ›› Issue (4): 1618-1626.DOI: 10.11949/0438-1157.20191332

• 催化、动力学与反应器 • 上一篇    下一篇

CeO2改性WO3/g-C3N4光催化氧化脱硫性能

刘帅1(),李学雷2,王烁天1,李旭贺1,王彦娟1,苑兴洲1,张健1(),封瑞江1   

  1. 1.辽宁石油化工大学化学化工与环境学部,辽宁 抚顺 113001
    2.营口理工学院化学与环境工程系,辽宁 营口 115014
  • 收稿日期:2019-11-05 修回日期:2020-01-21 出版日期:2020-04-05 发布日期:2020-04-05
  • 通讯作者: 张健
  • 作者简介:刘帅(1996—),男,硕士研究生,626060053@qq.com
  • 基金资助:
    辽宁省自然科学基金项目(20170540475)

WO3/g-C3N4 modified by CeO2 and its oxidation and desulfurization properties

Shuai LIU1(),Xuelei LI2,Shuotian WANG1,Xuhe LI1,Yanjuan WANG1,Xingzhou YUAN1,Jian ZHANG1(),Ruijiang FENG1   

  1. 1.College of Chemistry, Chemical Engineering and Environmental Engineering, Liaoning Shihua University, Fushun 113001, Liaoning, China
    2.Department of Chemical and Environmental Engineering, Yingkou Institute of Technology, Yingkou 115014, Liaoning, China
  • Received:2019-11-05 Revised:2020-01-21 Online:2020-04-05 Published:2020-04-05
  • Contact: Jian ZHANG

摘要:

以钨酸铵、六水硝酸铈、尿素为原料,采用熔融法制备CeO2-WO3/g-C3N4催化剂,并对样品进行XRD、UV-Vis、TEM、PL和XPS表征。结果表明:CeO2的引入可以提高WO3在g-C3N4上的分散度,抑制光生电子空穴对的复合,同时Ce4+/Ce3+良好的储氧放氧能力有利于氧空位和活性氧的生成,从而有利于WO3/g-C3N4催化剂的催化性能。在以高压钠灯模拟可见光源的条件下,以过氧化羟基异丙苯为氧化剂,考察了CeO2的加入量对催化剂氧化二苯并噻吩(DBT)性能的影响,结果表明:最佳的CeO2引入量为5%(质量分数),在80℃、氧硫摩尔比(O/S)为5.0的反应条件下,反应180 min时DBT在WO3/g-C3N4和CeO2-WO3/g-C3N4催化剂的作用下转化率分别为72.9%和86.4%,且改性后的催化剂可以循环使用8次而催化活性没有明显降低。

关键词: CeO2, 分布, 储氧放氧能力, 氧空位, 氧化, 催化剂

Abstract:

Using ammonium tungstate, cerium nitrate hexahydrate, and urea as raw materials, CeO2-WO3 / g-C3N4 catalyst was prepared by the melt method, and the samples were characterized by XRD, UV-Vis, TEM, PL, and XPS. XRD characterization results show that the introduction of CeO2 can improve the dispersion of active component WO3 on g-C3N4, and XPS characterization indicates the good oxygen storage and release capacity of Ce4+/Ce3+ is conducive to the formation of oxygen vacancy and reactive oxygen species. The PL characterization also indicates that the introduction of CeO2 can capture electrons and thus inhibits photogenic electron hole pair recombination. The introduction of the CeO2 for the catalytic activity of compound photocatalysis was investigated by oxidation and desulfurization experiment, the high-pressure sodium lamp was used to simulate visible light source, using the mixture of n-heptane and dibenzothiophene (DBT) as a simulation oil. Experimental results show that in 80℃, O/S molar ratio 5.0, 5% (mass fraction) CeO2 payload, 180 min of reaction conditions, the introduction of CeO2 catalyst on the oxidation of DBT in n-heptane conversion rate was 86.4%, higher than WO3/g-C3N4 on the oxidation of DBT conversion rate 72.9%. The characterization results and oxidation desulfurization experiments showed that the introduction of CeO2 could interact well with WO3/g-C3N4, thus improving the activity of the composite photocatalyst.

Key words: CeO2, distribution, oxygen storage and release capacity, oxygen vacancy, oxidation, catalyst

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