稀土杂多酸盐光催化降解活性染料废水的研究

制备了稀土杂多酸盐Na13[Yb(TiW11O39)2].xH2O。采用稀土杂多酸盐作为光催化剂,研究了其对模拟染料废水甲基橙溶液的光催化脱色降解的影响。实验结果表明,稀土杂多酸盐对染料废水有较好的光催化降解效果。讨论了影响光催化降解效果的几个重要因素:溶液初始酸度、催化剂投加量、溶液初始质量浓度等。最后,在300 W紫外灯光照下,研究了该稀土杂多酸盐降解10 mg/L甲基橙溶液的动力学。     

Na7Co（H2O）CrW11O39·14H2O光催化降解孔雀石绿的研究

以取代型杂多酸盐Na7Co(H2O)CrW11O39.14H2O为光催化剂。在紫外灯辐射下,研究了模拟染料废水孔雀石绿的光催化降解的反应,讨论了催化剂投加量、孔雀石绿的初始质量浓度、溶液的pH值等对孔雀石绿降解率的影响。结果表明,孔雀石绿溶液光催化降解的最佳条件为:pH值为2,催化剂投加量为2 mg,孔雀石绿的初始质量浓度为5 mg/L,经15 W紫外灯照射1 h后,其降解率为90.94%。     

Ti3(PW12O40)4/TiO2-WO3的制备及光催化降解甲基橙的研究

制备了新型固载杂多酸盐光催化荆Ti3(PW12O40)4/TiO2-WO3,并用傅里叶红外光谱法、X衍射法等对其进行了表征.以光催化降解染料废水甲基橙为探针反应,用正交实验考察了制备条件对催化剂的光催化活性的影响.探讨了催化荆投加量,溶液pH值,甲基橙初始浓度等对光催化降解效果的影响以及催化剂的重复使用性.最后,测定了反应动力学参数.     

Ti3(PW12O40)4/TiO2-WO3的制备及光催化降解甲基橙的研究

制备了新型固载杂多酸盐光催化荆Ti3(PW12O40)4/TiO2-WO3,并用傅里叶红外光谱法、X衍射法等对其进行了表征.以光催化降解染料废水甲基橙为探针反应,用正交实验考察了制备条件对催化剂的光催化活性的影响.探讨了催化荆投加量,溶液pH值,甲基橙初始浓度等对光催化降解效果的影响以及催化剂的重复使用性.最后,测定了反应动力学参数.     

US/Fe~(3+)/H_2O_2体系超声催化降解甲基橙的研究

采用US/Fe3+/H2O2体系超声催化降解甲基橙,考察了超声波功率、Fe3+初始质量浓度、H2O2用量、甲基橙溶液的初始质量浓度及初始pH值对超声催化降解甲基橙的影响,初步探讨了其降解动力学规律。结果表明,US/Fe3+/H2O2体系能有效降解甲基橙,且超声波与Fenton试剂对甲基橙废水的降解存在强烈的协同作用;在pH=3、超声波功率500 W、Fe3+和H2O2的初始质量浓度分别为30 mg/L和150 mg/L时,对含30 mg/L的甲基橙溶液降解120 min,其去除率达到99.5%;甲基橙的超声催化降解符合一级反应动力学规律,且甲基橙的一级反应速率常数随其初始质量浓度增大而降低。     

Fe_2O_3/Al_2O_3催化剂制备及催化降解酸性染料废水

以γ-Al2O3>为载体,采用浸渍-焙烧法制备了Fe2O3/Al2O3催化剂.并将其用于催化降解模拟酸性大红-3R染料废水.对于质量浓度为1 000 mg/L的高浓度酸性大红-3R染料废水,最佳的处理工艺条件为:温度60℃、pH=3.0、H2O2投加质量浓度9.4g/L、催化剂投加质量浓度1.5 g/L.在此工艺条件下酸性大红染料废水的降解率为99%,CODCr的去除率>83%.而对于质量浓度≤100 mg/L的酸性大红-3R染料废水在此条件下的降解速率接近100%.且催化剂连续使用6次后仍有较高的催化活性.     

11-钨钛杂多酸盐催化合成乙酸正丁酯

合成了4种具有Keggin结构的11-钨钛多元杂多酸盐K6[MTiW11(H2O)O39](M=Cu,Zn,Cd,Ni),并以所合成的杂多酸盐催化合成乙酸正丁酯。探讨了醇、酸摩尔比,催化剂的用量,反应时间和反应温度对酯化率的影响。结果表明,反应适宜条件为:醇、酸摩尔比为1.0,催化剂用量为原料质量的1.0%,反应温度为120℃,反应时间为5.0 h。乙酸正丁酯的酯化率为80%以上。     

复合材料PW_(12)/PANI/SnO_2光催化降解龙胆紫的动力学研究

以龙胆紫染料废水为探针反应,研究了催化剂PW12/PANI/Sn O2的催化性能,探讨了催化剂的用量和龙胆紫溶液的浓度对光催化降解效果的影响。结果表明,龙胆紫溶液光催化降解的最佳条件为:染料的起始质量浓度为10 mg/L,p H值为7,催化剂的最佳用量为300 mg/L,在30W紫外灯照射下,降解率可达96.23%。该催化剂对龙胆紫染料的降解为一级动力学反应。     

11-钨锌杂多酸盐催化合成乙酸乙酯

合成了K8[CdZnW11O39（H2O）]、K8[NiZnW11O39（H2O）]和K8[CuZnW11O39（H2O）]3种具有Keggin结构的钨锌混配型杂多酸盐催化剂,以无水乙醇和冰乙酸为原料,催化合成乙酸乙酯。探讨了酸醇物质的量的比,催化剂的用量,反应时间和反应温度对酯化率的影响及催化剂的重复使用情况。结果表明反应最佳条件为：酸醇摩尔比为2.0,催化剂用量为原料质量的1%,反应时间为6.0 h,反应温度80℃,催化剂在连续使用5次情况下活性无明显下降。     

过渡金属取代钨锰三元杂多酸盐的合成表征及催化活性

采用直接合成法合成K6[MnCu(H2O)W11O39],K5[MnFe(H2O)W11O39],K6[MnCo(H2O)W11O39],K6[MnZnH2(O)W11O39],K6[MnNi(H2O)W11O39],K6[MnCd(H2O)W11O39]等6种过渡金属取代的钨锰杂多酸盐,利用红外光谱、紫外光谱对合成产物的结构进行了表征。结果表明,6种杂多阴离子具有Keggin结构。利用酯化反应考察了所合成催化剂的催化活性,并且确定了最佳催化反应条件:酸醇物质的量比1∶1,催化剂用量占原料总量的1.5%,反应时间4h,反应温度控制在120℃。结果表明,过渡金属取代钨锰三元杂多酸对乙酸正丁酯的催化产率95%以上。     

a-SiW11Mn／四丁基溴化铵电荷转移配合物的合成及热分解动力学研究

文章合成了Keggin结构锰取代杂多钨硅酸盐四丁基溴化胺电荷转移配合物,用元素分析、UV、TG-DTG等方法对其进行了表征。结果显示该化合物仍保持杂多阴离子的Keggin结构的基本特征。用TG-DTG的方法研究了R-（TBA）4H2[SiWIiMn（H20）O39]·14H2O的热解机理和动力学,采用了Doyle方程和Coats-Redfem方程对非等温动力学数据进行了分析,得到了热分解反应的机理函数,动力学参数以及分解反应的活化能E和InA。     

Hydrogen Evolution Over Heteropoly Blue-Sensitized Pt/TiO2 Under Visible Light Irradiation

We report the visible light-induced hydrogen generation over heteropoly blue (HPB) sensitized Pt/TiO₂ photocatalyst. HPB was obtained via UV-induced reduction of heteropoly acid K₅(BW₁₁O₃₉H₄) · 12.8H₂O (BW₁₁) in glycerol aqueous solution. The photocatalytic activity for hydrogen generation was found to be dependent on the concentration of HPB in the solution.     

在微乳液/离子液体协同增敏下测定样品中的硅

以OP(聚乙二醇辛基苯基醚)/正戊醇/正庚烷/水微乳液与1-丁基-3-甲基咪唑氯盐为介质,建立了硅的结晶紫-硅钼杂多酸光度分析法,研究了显色时间、微乳液与离子液体比例和用量、体系酸度、钼酸铵和结晶紫用量对显色反应的影响。结果表明,离子缔合物的最大吸收波长为545 nm,表观摩尔吸光系数为1.2×10~5L/(mol·cm),硅质量浓度在0.024~0.24 mg/L内符合朗伯-比尔定律。该方法的检出限为2.0×10~(-6)g/L,可用于自来水、雨水、钢样中微量硅的测定,相对标准偏差﹤3%,加标回收率为98%~106%。     

Keggin型磷钼矾杂多化合物在氧化羰基化合成碳酸二苯酯中的应用

采用酸化乙醚萃取法制备了Keggin型磷钼矾杂多酸及其盐,并采用FT-IR和BET对磷钼矾杂多酸进行了表征。考察了磷钼矾杂多化合物在苯酚氧化羰基化合成碳酸二苯酯反应中的性能。结果表明,高含钒量的杂多酸具有更好的催化活性,它们的活性顺序为:H6PMo9V3O40>H5PMo10V2O40>H4PMo11VO40。用不同价态的金属阳离子取代H6PMo9V3O40中的氢离子后,CeH3PMo9V3O40表现出了最好的性能,DPC的收率达6.7%;当进一步用VO2+取代了CeH3PMo9V3O40中的氢离子后,Ce[VO]1.5PMo9V3O40的性能更好,碳酸二苯酯的收率达10.2%。     

杂多酸/Fe3O4磁性催化剂的制备及其对次甲基蓝溶液的降解

采用浸渍法将磷钨酸、磷钼酸和硅钨酸等杂多酸负载在Fe3O4磁性材料上,并将杂多酸/Fe3O4磁性材料作为光催化剂用于降解次甲基蓝溶液,考察了光源类型（紫外光与太阳光）、杂多酸种类及催化剂用量等对光催化降解效果的影响。结果表明,在250 W汞灯照射、次甲基蓝溶液浓度20 mg·L-1、降解体系pH=5.5、光催化剂用量30 mg和光催化120 min条件下,次甲基蓝降解率达85%,负载型杂多酸/Fe3O4磁性催化剂对次甲基蓝的降解效果明显优于相应单一的Fe3O4或杂多酸催化剂。     

α-SiW_(11)Ni掺杂聚苯胺的合成及热分解动力学研究

以乙二醇(EG)的水溶液为反应媒介,制备了Keggin结构杂多酸盐α-K5H[Si W11Ni(H2O)O39].15H2O掺杂的导电聚苯胺材料,用元素分析、IR、TG-DTA、XRD等方法对其进行了表征。结果显示,该化合物仍保持杂多阴离子的Keggin结构的基本特征。同时,采用TG-DTA技术研究了标题化合物在氮气气氛中的热分解机理及非等温动力学,用MKN法、Coats-Redfern法和唐万军法对配合物的非等温动力学数据进行分析,得出了热分解反应的机理函数、动力学参数以及3步分解反应的活化能E和lnA。     

Conduction of (Na,Ce) doped Bi5Ti3FeO15 ceramics after different annealing processes

Abstract

Abstract

Bi_5?xNa_x/2Ce_x/2Ti₃FeO₁₅ (BNTF-100x, x?=?0, 0·05, 0·10, 0·20, 0·30, 0·40 and 0·60) ceramics were prepared via solid state sintering process. With x increasing, the resistivity increases at first and then decreases. The lower the concentration of oxygen vacancies, caused by more (Na,Ce) dopant adding, the less the deep trap energies in the band gap for the activated electrons to be mobile. For the samples containing high concentration of oxygen vacancies, the conductivities are higher when they are annealed in the air and oxygen than that in the vacuum. On the contrary, for the samples containing low concentration of oxygen vacancies, the conductivities of the samples in different annealing conditions behave quite the same way. Most (Na,Ce) doped Bi₅Ti₃FeO₁₅ ceramics exhibit intrinsic conduction at high temperatures with corresponding activation energies of 1·1–1·6 eV, while the extrinsic conduction has a close relationship with the concentration of oxygen vacancies and the activation ability of electrons.     

Hydrothermal Synthesis, Characterization and Electrocatalytic/Photocatalytic Activities of New Polyoxometalate Based Hybrid Compound

In this paper, we report the hydrothermal synthesis and physicochemical characterization of a complicated high-dimensional and high-connected POM-based hybrid compound, namely, [Ag₃(pytz)₂(H₂O)]₂.[HAgGeMo₁₂O₄₀]·H₂O, which has been synthesized by reactions of pyridyltetrazoles and Keggin POMs. X-ray diffraction and crystallographic analyses reveals that the new compound exhibits POMs chains pillaring transition-metal complexes, which represents the highest coordination number of Keggin POMs up to date. Moreover, the new compound bulk-modified carbon-paste electrode (1-CPE) displays good electrocatalytic activity toward the reduction of nitrite, and the result of the photocatalytic activities indicates that the new compound presents better degradation activity and may be a potential photocatalyst to oxidative decomposition of rhodamine B dye in the presence of crystals [Ag₃(pytz)₂(H₂O)]₂·[HAgGeMo₁₂O₄₀]·H₂O catalyst under ultraviolet-light irradiation.     

Construction of Two One-Dimensional Coordination Polymers by 5-Chlorosalicylic Acid Plus N-Donor Ligand: Synthesis,Structure and Catalytic Properties

Two novel coordination polymers, namely, [Co(HL5)(4,4′-bpy)_1.5(H₂O)₂]_n·n(HL5) (1) and [Zn(HL5)₂(4,4′-bpy)]_n (2) (H₂L5 = 5-chlorosalicylic acid), have been hydrothermally synthesized through the reaction of 5-chlorosalicylic acid with divalent transition-metal salts in the presence of N-donor ancillary coligand (4,4′-bpy = 4,4′-bipyridine). Polymer 1 exhibits one-dimensional (1D) infinite ladderlike chain, which is extended into a 2D supramolecular network via O–H···O hydrogen-bonding interactions. In polymer 2, 4,4′-bpy acts as a bidentate ligand to bind Zn(II) ions to form a [Zn(4,4′-bpy)]_n infinite zigzag chain structure, which is linked by hydrogen bonds into a 3D suparmolecular assembly. Also, IR spectra, powder X-ray diffraction, fluorescence Properties and thermal decomposition process of polymers were investigated. Moreover, both compounds exhibit catalytic properties on degradation of methyl orange in Fenton-like process.