MoO_(3-x)/SiO_(2)催化剂的制备及其在氧化脱硫中的应用  

Preparation of MoO_(3-x)/SiO_(2)catalysts and application in oxidative desulfurization

作　　者：刘红利[1] 单媛媛 杜朕屹 LIU Hong-li;SHAN Yuan-yuan;DU Zhen-yi(State Key Laboratory of Clean and Efficient Coal Utilization,Taiyuan University of Technology,Taiyuan 030024,China;College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学省部共建煤基能源清洁高效利用国家重点实验室,山西太原030024 [2]太原理工大学材料科学与工程学院,山西太原030024

出　　处：《现代化工》2023年第2期173-179,共7页Modern Chemical Industry

基　　金：山西省应用基础研究计划面上青年基金项目(201901D1211098)。

摘　　要：以钼酸铵为前驱体、亲水性SiO_(2)为载体,采用等体积浸渍法制备了负载型MoO_(3-x)/SiO_(2)系列催化剂。利用X射线衍射(XRD)、拉曼光谱(Raman)、紫外光谱(UV-Vis)、N_(2)吸附-脱附、X射线光电子能谱仪(XPS)和氢气程序升温还原(H_(2)-TPR)等技术手段对催化剂性质进行表征。以乙腈为萃取剂、过氧化氢为氧化剂的氧化脱硫反应中,研究了催化活性与催化剂表面性质的内在规律关系。结果表明,MoO_(3-x)活性组分的团聚是抑制氧化脱硫活性的主要原因,适宜的焙烧温度有利于获得所需活性位点且分散性高的催化剂,可有效对H2O_(2)快速活化,提高DBTs脱硫率。在焙烧温度为350℃、O/S摩尔比为3、反应温度为60℃的最佳脱硫条件下,苯并噻吩(BT)、二苯并噻吩(DBT)和4,6-二甲基二苯并噻吩(4,6-DMDBT)的脱除率分别为77.2%、99.3%、96.4%。该催化体系中DBT的脱除率可达到国家脱硫标准(<10μg/g)。A series of supported MoO_(3-x)/SiO_(2)catalysts are prepared via equal volume immersion method by using hydrophilic SiO_(2)as supporter and ammonium molybdate as precursor.The prepared catalysts are characterized by mean of N2adsorption-desorption,X-ray diffraction,Raman spectroscopy,UV-Vis spectroscopy,X-ray photoelectron spectroscopy and hydrogen temperature-programmed reduction.In an oxidative desulfurization process using acetonitrile as extractant and H_(2)O_(2)as oxidant,the intrinsic rule relationship between the catalytic activity and the surface properties of the catalyst is studied.Study results indicate that the agglomeration of MoO_(3-x)active is the main reason to inhibit the oxidative desulfurization activity.A suitable calcination temperature is important to obtain the catalysts with desired active sites,high dispersion for the rapid activation of H_(2)O_(2)and an improved desulfurization rate.The removal rates of benzothiophene,dibenzothiophene and 4,6-dimethyldibenzothiophene are 77.2%,99.3%and 96.4%,respectively under the conditions that the calcination temperature is 350℃,the optimal O/S ratio is 3 and the optimal reaction temperature is 60℃.Advantageously,the present catalytic system can achieve China’s national desulfurization standard(<10 ppm)with respect to benzothiophene.

关 键 词：二苯并噻吩 氧化 脱硫 液体燃料 焙烧温度 

分 类 号：TE624[石油与天然气工程—油气加工工程]