高等学校化学学报 ›› 2018, Vol. 39 ›› Issue (2): 247.doi: 10.7503/cjcu20170665

• 物理化学 • 上一篇    下一篇

磷酸盐的添加对甲烷氧化偶联反应镧基催化剂的影响

白燕, 夏文生(), 翁维正, 连孟水, 赵明全, 万惠霖()   

  1. 厦门大学化学化工学院, 固体表面物理化学国家重点实验室,醇醚酯化工清洁生产国家工程实验室, 福建省理论计算化学重点实验室, 厦门 361005
  • 收稿日期:2017-09-30 出版日期:2018-02-10 发布日期:2017-12-23
  • 作者简介:联系人简介: 夏文生, 男, 博士, 教授, 主要从事催化和理论化学研究. E-mail: wsxia@xmu.edu.cn; 万惠霖, 男, 博士, 教授, 博士生导师, 中国科学院院士, 主要从事催化和理论化学研究. E-mail: hlwan@xmu.edu.cn
  • 基金资助:
    国家自然科学基金(批准号: 21373169)和教育部创新团队发展计划项目(批准号IRT1036)资助

Influence of Phosphate on La-based Catalysts for Oxidative Coupling of Methane

BAI Yan, XIA Wensheng*(), WENG Weizheng, LIAN Mengshui, ZHAO Mingquan, WAN Huilin*()   

  1. State Key Laboratory of Physical Chemistry of Solid State Surfaces,National Engineering Laboratory for Green Chemical Productions of Alcohols-Ethers-Esters,Fujian Province Key Laboratory of Theoretical and Computational Chemistry,College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
  • Received:2017-09-30 Online:2018-02-10 Published:2017-12-23
  • Contact: XIA Wensheng,WAN Huilin E-mail:wsxia@xmu.edu.cn;hlwan@xmu.edu.cn
  • Supported by:
    † Supported by the National Natural Science Foundation of China(No.21373169) and the Program for Changjing Scholars and Innovative Research Team in University of Ministry of Education, China(No.IRT1036)

摘要:

采用柠檬酸法制备了不同含量磷酸盐修饰的镧基催化剂, 考察了磷酸盐的添加对镧基催化剂甲烷氧化偶联反应(OCM)活性的影响, 并借助X射线衍射(XRD)、 O2-程序升温脱附(O2-TPD)及X射线光电子能谱(XPS)等手段对催化剂的理化性质进行了表征. 结果表明, 随着磷酸盐加入量的增大, 催化剂样品的粒径逐渐减少, 催化剂的物相由La2O3向La3PO7和LaPO4逐步转变. 当催化剂的物相由La2O3和适量的La3PO7构成时, 催化剂具有较多的表面缺陷位点数和较大的亲电氧物种/晶格氧物种比值, 并呈现出良好的OCM反应性能.

关键词: 磷酸盐, 甲烷氧化偶联, 氧化镧, 磷酸氧镧

Abstract:

A series of La-based catalysts promoted by different contents of PO43- was synthesized by the citric acid method and their catalytic performance for oxidative coupling of methane(OCM) was investigated to clarify the effect of PO43- on La-based catalyst. With characterizations such as X-ray powder diffraction(XRD), O2-temperature programmed desorption(O2-TPD) and X-ray photoelectron spectroscopy(XPS), we studied the physicochemical properties of the catalysts. The results showed that the phases of the catalysts were changed from La2O3, La3PO7 to LaPO4 along with the decreased size when phosphate added. If the catalyst was composed of two phases(La2O3 and right amount of La3PO7), it showed better performances in OCM, which corresponded to the more quantities of surface defect sites and the larger ratio of electrophilic oxygen species/lattice oxygen species than other samples.

Key words: Phosphate, Oxidative coupling of methane, Lanthanum oxide, Lanthanum oxyphosphate

TrendMD: