SiO_(2)-Fe_(2)O_(3)及SO_(4)^(2-)/SiO_(2)-Fe_(2)O_(3)固体酸的制备及催化四氢呋喃聚合性能  

Preparation of SiO_(2)-Fe_(2)O_(3)and SO_(4)^(2-)/SiO_(2)-Fe_(2)O_(3)Solid Acid and Their Catalytic Performance for Tetrahydrofuran Polymerization

作　　者：盖媛媛[1] 李海涛[2] GE Yuan-yuan;LI Hai-tao(Department of Chemical Engineering,Yulin Vocational and Technical College,Yulin Shannxi 719000,China;Engineering Research Center of Ministry of Education for Fine Chemicals,Shanxi University,Taiyuan Shanxi 030006,China)

机构地区：[1]榆林职业技术学院化学工程系,陕西榆林719000 [2]山西大学精细化学品工程研究中心,山西太原030006

出　　处：《当代化工》2022年第10期2357-2360,共4页Contemporary Chemical Industry

基　　金：国家自然科学基金(项目编号:22075167);榆林市科技计划项目(项目编号:CXY-2020-017-04);高新区科技计划项目(项目编号:cxy-2020-42)。

摘　　要：分别以正硅酸乙酯和硝酸铁为前驱体,采用溶胶-凝胶法制备一系列不同Fe/Si比的SiO_(2)-Fe_(2)O_(3)复合氧化物,并将制备的SiO_(2)-Fe_(2)O_(3)复合氧化物浸渍硫酸,调控其酸性质,获得SO_(4)^(2-/SiO_(2)-Fe_(2)O_(3)固体酸材料。通过FTIR、NH_(3)-TPD对SiO_(2)-Fe_(2)O_(3)复合氧化物和SO_(4)^(2-/SiO_(2)-Fe_(2)O_(3)固体酸催化剂的结构和酸性质进行表征,同时将催化剂用于四氢呋喃聚合反应,考察其催化活性。结果表明:SiO_(2)和Fe_(2)O_(3)复合形成的氧化物红外光谱图与纯SiO_(2)相似,NH_(3)-TPD结果表明其具有丰富的弱酸和中强酸性中心。随着Fe/Si比的增加,SiO_(2)-Fe_(2)O_(3)复合氧化物的总酸量先增加后减少,催化活性也呈现先增加后减少的趋势。Fe/Si比为0.16时,总酸量最多,催化活性也最高。SiO_(2)-Fe_(2)O_(3)复合氧化物浸渍硫酸后,酸量增加;当Fe/Si比增至0.08时,开始出现强酸中心,且随着Fe/Si比的增加,强酸中心的数量增加;随着强酸中心的出现,SO_(4)^(2-/SiO_(2)-Fe_(2)O_(3)的四氢呋喃聚合反应的催化活性消失,说明强酸位的存在抑制了反应的进行。A series of SiO_(2)-Fe_(2)O_(3)composite oxides with different Fe/Si ratios were prepared by sol-gel method using tetraethyl silicate and ferric nitrate as precursors respectively.SO_(4)^(2-/SiO_(2)-Fe_(2)O_(3)solid acid materials were obtained by impregnating SiO_(2)-Fe_(2)O_(3)composite oxides with sulfuric acid to regulate their acid properties.The structure and acid properties of SiO_(2)-Fe_(2)O_(3)composite oxide and SO_(4)^(2-/SiO_(2)-Fe_(2)O_(3)solid acid catalysts were characterized by FTIR and NH_(3)-TPD.The catalytic activities for tetrahydrofuran polymerization were investigated.The results showed that the FTIR spectra of SiO_(2)-Fe_(2)O_(3)composite oxides were similar to that of pure SiO_(2),and there were abundant weak and medium strong acid sites by NH_(3)-TPD spectra.With the increase of Fe/Si ratio,the total acid content of SiO_(2)-Fe_(2)O_(3)composite oxides increased first and then decreased,and the catalytic activity also increased first and then decreased.The total acid content and the catalytic activity were both reached to the highest value as the Fe/Si ratio increased to 0.16.After SiO_(2)-Fe_(2)O_(3)composite oxides were impregnated with sulfuric acid,the amount of acid increased.The strong acid centers appeared when the Fe/Si ratio increased to 0.08,and the strong acid amount increased with the increase of Fe/Si ratio.With the appearance of strong acid centers,the catalytic activity of SO_(4)^(2-/SiO_(2)-Fe_(2)O_(3)for tetrahydrofuran polymerization disappeared,that indicated the reaction was inhibited by the presence of strong acid sites.

关 键 词：SiO_(2)-Fe_(2)O_(3)复合氧化物 SO42-/SiO_(2)-Fe_(2)O_(3)固体酸 酸量 四氢呋喃聚合 催化活性 

分 类 号：TQ032.41[化学工程]