(PMo_(12))(HPy)_(3)的合成、表征及催化氧化碘离子性能  

Synthesis,characterization of (PMo_(12))(HPy)_(3) and its catalytic oxidation property of iodide ion

作　　者：郭军 张太文[2] 张丹 GUO Jun;ZHANG Taiwen;ZHANG Dan(State Key Laboratory for Efficient Utilization of Medium and Low Grade Phosphate Rock and Its Associated Resources,Wengfu(Group)Co.,Guiyang 550014,China;School of Chemistry and Materials Science,Guizhou Normal University,Guiyang 550001,China)

机构地区：[1]瓮福(集团)有限责任公司中低品位磷矿及其共伴生资源高效利用国家重点实验室,贵州贵阳550014 [2]贵州师范大学化学与材料科学学院,贵州贵阳550001

出　　处：《无机盐工业》2023年第4期125-132,共8页Inorganic Chemicals Industry

基　　金：国家自然科学基金项目(21862005);贵州省科技厅计划项目(黔合基础[2019]1457,黔科合支撑[2019]2835,黔科合平台人才[2018]5769);贵州省教育厅青年科技人才成长项目(黔科合KY字[2018]126)。

摘　　要：采用水热法合成了一例新的多酸基有机-无机杂化物非均相催化剂,并通过X-射线单晶衍射、傅里叶变换红外光谱(IR)、热重分析测试(TG)、X-射线衍射分析(XRD)、元素分析对其进行了表征。X-射线单晶衍射分析表明,化合物的结构式为(PMo_(12)O_(40))(C_(5)H_(6)N)_(3)[简写为(PMo_(12))(HPy)_(3),其中PMo_(12)表示PMo_(12)O_(40),HPy表示C_(5)H_(6)N],属于正交晶系,Cmca空间群,晶胞参数a=1.91031(8)nm、b=1.53822(6)nm、c=1.46063(6)nm、α=β=γ=90°、V=4.2920(3)nm^(3)、Z=4、R_(1)=0.0629、wR_(2)=0.1324。化合物由2-吡啶甲酸在高温高压下原位脱羧后形成的质子化的3个吡啶环、1个经典的Keggin型[PMo_(12)O_(40)]^(3-)构成,每个次级单元之间通过静电等相互作用进一步形成一维(1D)~二维(2D)结构。催化研究表明:(PMo_(12)O_(40))(C_(5)H_(6)N)_(3)在催化过氧化氢氧化碘离子为碘单质过程中,其化学反应动力学近似准一级反应,反应速率高达1.205×10^(-5)mol/(L·s),相对于室温下未添加催化剂时提高了1839.7倍,该非均相催化剂重复使用5次后转化率仍高达99.96%,表现出较好的催化活性与可重复性。A new polyoxometalate⁃based organic⁃inorganic hybrid heterogeneous catalyst was synthesized by hydrothermal synthesis,and it was characterized by X-ray single crystal diffraction,fourier transform infrared spectroscopy(IR),thermo⁃gravimetric analysis(TG),X-ray diffraction analysis(XRD)and elemental analysis.X-ray single crystal diffraction analysis showed that the structural formula of the compound was(PMo_(12)O_(40))(C_(5)H_(6)N)_(3)[short for(PMo_(12))(HPy)_(3),PMo_(12) was PMo_(12)O_(40),HPy was C_(5)H_(6)N],which was belonged to orthorhombic system,Cmca space group,unit cell parameters a=1.91031(8)nm,b=1.53822(6)nm,c=1.46063(6)nm,α=β=γ=90°,V=4.2920(3)nm^(3),Z=4,R_(1)=0.0629,wR_(2)=0.1324.The compound was composed of three protonated pyridine rings and one classical Keggin type[PMo_(12)O_(40)]^(3-)after in⁃situ de⁃carboxylation of 2-picolinic acid under high temperature and high pressure,and each secondary unit was formed by electro⁃static and other interactions to form one⁃dimensional(1D)to two⁃dimensional(2D)structures.Catalytic studies showed that:(PMo_(12))(HPy)_(3) in the process of catalyzing the oxidation of iodide ion to iodine element in hydrogen peroxide,the chemical reaction kinetics was approximately a first⁃order reaction,and the reaction rate was as high as 1.205×10^(-5) mol/(L·s),which was 1839.7 times higher than that no catalyst was added.When the heterogeneous catalyst was reused for 5 times,the con⁃version rate was still as high as 99.96%,showing good catalytic activity and repeatability.

关 键 词：多金属氧酸盐 化合物表征 催化性能 碘离子 

分 类 号：TQ124.6[化学工程—无机化工]