Dawson结构磷钨酸铁的制备、表征及催化合成四氢呋喃  

Preparation,characterization and catalytic application on tetrahydrofuran synthesis of Dawson structure iron phosphotungstate

作　　者：曹小华[1] 徐常龙[1] 吴海英 周德志[1] 雷艳虹[1] 

机构地区：[1]九江学院化学与环境工程学院,江西九江332005 [2]江西省九江市第三中学,江西九江330006

出　　处：《华中师范大学学报（自然科学版）》2016年第2期232-237,共6页Journal of Central China Normal University：Natural Sciences

基　　金：国家自然科学基金项目(21161009);江西省自然科学基金项目(20132BAB203004;20122BAB213001);江西省教育厅科技项目(GJJ14731;GJJ12616);九江学院科技项目(2013KJ005)

摘　　要：利用复分解法制备出新型Dawson结构磷钨酸铁催化剂(FeH3P2W18O62·nH2O),并采用FT-IR、UV-Vis、SEM、EDS、Py-IR和NH3-TPD对其进行表征,考察了此催化剂在催化1,4-丁二醇液相脱水环化法合成四氢呋喃(THF)反应中的催化活性.FT-IR、UV-Vis及EDS表征结果表明自制磷钨酸铁催化剂具有Dawson结构.Py-IR及NH3-TPD测试结果显示:FeH3P2W18O62·nH2O同时具有Brnsted酸中心和Lewis酸中心.Fe3+离子取代使H6P2W18O62·nH2O催化剂表面弱酸中心和强酸中心的酸强度增大,且Lewis酸比例增大.SEM照片可观察到自制磷钨酸铁呈球状.在优化工艺条件下,w(FeH3P2W18O62·nH2O)=2.3%(基于反应物质量),反应温度为185℃,反应时间为40min,THF收率为94.1%.该催化剂具有良好的重复使用性,第5次使用时收率达78.5%.Iron phosphotungstate（FeH3P2W18O62·nH2O）was prepared by double decomposition method and characterized by FT-IR,UV-Vis,SEM,EDS,Py-IR and NH3-TPD.Then it was used as catalyst in tetrahydrofuran（THF）synthesis from 1,4-butanediol.The results of FT-IR,UV-Vis and EDS showed that the self-prepared iron phosphotungstate contained primary dawson structure.The SEM image showed that FeH3P2W18O62·nH2O formed spheroid bodies.Data of Py-IR and NH3-TPD revealed that FeH3P2W18 O62 has both Brnsted and Lewis acid centers.Besides,the acid strength of the weak and strong acid sites,as well as the Lewis acid proportion on the surface,increased after Fe3＋ions substituted by H＋.The optimal yield of THF reach94.1% after fourty minutes reaction at 185℃ with the mass ratio of catalyst to 1,4-butanediol being 2.3%.Additionally,the yield of THF was able to reach 78.5% after five-time usage of the catalyst.

关 键 词：磷钨酸铁 DAWSON结构 酸中心 1 4-丁二醇 四氢呋喃 

分 类 号：TQ251.1[化学工程—有机化工] O643.3[理学—物理化学]