负载镧掺杂无定形二氧化钛的介孔光催化氧化脱硫催化剂  

Mesoporous Photocatalytic Oxidation Desulfurization Catalyst for Lanthanum Doped Amorphous Titanium Dioxide

作　　者：杨丽娜[1] 周效竹 张熙 李剑[1] YANG Lina;ZHOU Xiaozhu;ZHANG Xi;LI Jian(School of Petrochemical Engineering,Liaoning Petrochemical University,Fushun 113001,Liaoning,China;Sinopec Dalian Petrochemical Research Institute Co.,LTD.,Dalian 116000,Liaoning,China)

机构地区：[1]辽宁石油化工大学石油化工学院,辽宁抚顺113001 [2]中石化大连石油化工研究院有限公司,辽宁大连116000

出　　处：《硅酸盐学报》2024年第7期2206-2215,共10页Journal of The Chinese Ceramic Society

基　　金：辽宁省教育厅项目(LJQ2015062);辽宁省教育厅项目(L2016018);抚顺市科技发展项目(20131114)。

摘　　要：为了开发高活性油品光催化氧化脱硫催化剂,以样品La-TiO_(2)为活性组分,样品SBA-15为载体合成了以镧掺杂无定形二氧化钛为活性组分的介孔催化剂(La-TiO_(2)/SBA-15),采用X射线衍射(XRD)、X射线荧光光谱(XRF)、氮气吸附–脱附(BET)、透射电子显微镜(TEM)、傅里叶变换红外光谱(FT–IR)、紫外–可见光谱(UV–Vis)、光致发光光谱(PL)、X射线光电子能谱价带谱(VB–XPS)进行表征,应用于含二苯并噻吩(DBT)的模拟柴油及真实柴油的光催化氧化脱硫,同时提出光催化反应机理。催化活性从高到低为:样品La-TiO_(2)/SBA-15,样品La-TiO_(2),样品TiO_(2),样品SBA-15,这是因为样品SBA-15的高比表面积和有序介孔结构促进了活性组分的分散和DBT的扩散,镧掺杂拓宽了光响应范围,提高了吸光度,降低了光生电子–空穴的复合率。捕获实验表明,·O_(2)^(–)和h^(+)是主要活性中间物种。优化后工艺条件为催化剂用量1%(质量分数),氧化剂中氧原子与硫化物中硫原子摩尔比n(O)/n(S)=15:1,剂油体积比(V_((extractant))/V_((model fuel)))=1:1,脱硫率达95.12%,且循环使用4次后仍高于85%,真实柴油在催化剂用量3%(质量分数),n(O)/n(S)=20:1,V_((extractant))/V_((model fuel))=1:1的条件下脱硫率达64.7%。Introduction As a semiconductor material with superior optical properties,amorphous TiO_(2)with the valence band,conduction band,and bandgap structure of crystalline TiO_(2)is prone to forming a loose porous structure with more surface defects.During the photocatalytic reaction process,it can generate a large number of electron and hole capture traps,which is conducive to improving a photocatalytic efficiency.However,its photocatalytic activity still needs to be improved.Widening its absorption range,narrowing its band gap and promoting the migration of the internal electron-hole to the surface to react with the target product are all still the current important research aspects.Doping or loading is a normal modification method of TiO_(2).The doping with rare-earth element La is simple and effective,narrowing the band gap of TiO_(2)and reducing the energy consumption of photocatalytic reaction.To further improve the photocatalytic activity,loading La-TiO_(2)on SBA-15 can be an effective option.The high specific surface area and the mesopores of SBA-15 can be beneficial to the dispersion of the active component and the diffusion of reactants,thereby improving the photocatalytic performance.In this paper,TiO_(2)was firstly doped with La,and La-TiO_(2)was then supported on mesoporous molecular sieves SBA-15.The obtained catalyst La-TiO_(2)/SBA-15 was characterized and applied in the photocatalytic oxidation desulfurization for the model and real diesel oil.In addition,the photocatalytic reaction mechanism was also proposed.Methods 4 mmol tetrabutyl titanate was dropped slowly into a solution of 0.9 m L of deionized water with 10 m L of absolute ethanol under magnetically stirring until a white gel was generated.After stirring for 0.5 h,the white gel was aged at 25℃for 14 h,and then stirred at 40℃until the absolute ethanol was completely evaporated.This white powder becomes an amorphous TiO_(2)after drying at 100℃and grinding.The synthesis process of La-TiO_(2)was similar to that of amorphous TiO_(2).However,de

关 键 词：镧掺杂二氧化钛 介孔分子筛 负载 光催化氧化脱硫 

分 类 号：TQ174.75[化学工程—陶瓷工业]