化工学报 ›› 2020, Vol. 71 ›› Issue (4): 1627-1636.DOI: 10.11949/0438-1157.20191160

• 催化、动力学与反应器 • 上一篇    下一篇

杂多酸的共价负载及其对四氢噻吩氧化性能研究

刘叶峰(),左鹏,李瑞琪,焦纬洲,王蕊欣()   

  1. 中北大学化学工程与技术学院,山西 太原 030051
  • 收稿日期:2019-10-10 修回日期:2019-11-24 出版日期:2020-04-05 发布日期:2020-04-05
  • 通讯作者: 王蕊欣
  • 作者简介:刘叶峰(1988—),女,博士研究生,245470590@qq.com
  • 基金资助:
    山西省自然科学基金项目(201801D121069)

Covalently supported polyoxometalate and its catalytic oxidative desulfurization of tetrahydrothiophene

Yefeng LIU(),Peng ZUO,Ruiqi LI,Weizhou JIAO,Ruixin WANG()   

  1. School of Chemical Engineering and Technology, North University of China, Taiyuan 030051, Shanxi, China
  • Received:2019-10-10 Revised:2019-11-24 Online:2020-04-05 Published:2020-04-05
  • Contact: Ruixin WANG

摘要:

首先采用改进的Hummers法制备氧化石墨烯(GO),用3-氨丙基三甲氧基硅氧烷(KH540)对GO进行表面改性,制得氨基改性氧化石墨烯NH2-GO。然后,通过γ-(2,3-环氧丙基) 三甲氧基硅烷对单缺位的Dawson型磷钨酸盐K10[α-P2W17O61]·20H2O(P2W17)进行环氧基改性,制得环氧基改性的EPO-P2W17。最后,借助NH2-GO与EPO-P2W17之间的席夫碱反应实现P2W17在GO上的共价固载,制得复合催化剂P2W17/GO。采用FT-IR、UV-Vis、TG、XPS、TEM等对复合材料的结构和组成进行了表征。以四氢噻吩(THT)作为催化评价的对象,初步考察了P2W17/GO的催化氧化活性。实验结果表明,共价负载在GO上的P2W17分散性良好,且复合催化剂P2W17/GO对THT表现出良好的催化活性和高的选择性。较小的P2W17/GO用量(0.02 g)下,以H2O2为氧化剂,反应75 min,THT转化率达100%;相对于EPO-P2W17,其催化活性提高了1.7倍;其催化H2O2氧化THT的过程符合准一级动力学模型。此外,该催化剂具有良好的重复使用性。

关键词: 氧化石墨烯, Dawson型磷钨酸盐, 共价键合, 催化, 氧化脱硫

Abstract:

Firstly, the graphene oxide (GO) was prepared by the modified Hummers method, and modified with 3-aminopropyltrimethoxysilane to obtain NH2-GO containing amino groups. Then, the single lacunary Dawson type tungstophosphate K10[α-P2W17O61]·20H2O (P2W17) was modified with γ-(2,3-epoxypropoxy) propyltrimethoxysilane (EPO) to prepare EPO-P2W17 containing epoxy groups. Finally, P2W17 was covalently bonded onto GO through the reaction of EPO-P2W17 with NH2-GO to prepare P2W17/GO composite catalysts. The structure and composition of the composites were characterized by FT-IR, UV-Vis, TG, XPS, TEM, etc. Tetrahydrothiophene (THT) was used as the object of catalytic evaluation, and the catalytic oxidation activity of P2W17/GO was initially investigated. The results show that P2W17 covalent-supported on GO is well dispersed. And the oxidation process of THT catalyzed by P2W17/GO using H2O2 presented the high efficiency and selectivity. The conversion of THT could reach 100% at 75 min with H2O2 as oxidant under a small amount of P2W17/GO (0.02 g), and its catalytic activity is 1.7 times higher than that of EPO-P2W17. The catalytic oxidation of THT by P2W17/GO follows the quasi-first order kinetic model. More attractively, P2W17/GO could be well reused several times, stemming from the strong covalent bonding between P2W17 and GO surface.

Key words: graphene oxide, Dawson phosphotungstic acid, covalent immobilization, catalysis, oxidative desulfurization

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