摘要
随着工业化的发展,各种危及人类生存的有害物质越来越多地进入环境中,特别是工业染料废水的大量增加使水体污染问题更加突出。一些有毒有机污染物,由于它们的浓度低、结构稳定、并且难生物降解,用常规的污水处理方法很难除去。光催化降解法是近三十年来发展起来的废水处理新方法,具有运行稳定、处理效果好、无二次污染等特点。
本论文合成了8种组成为K_n[PW_9V_2O_(39)Z(H_2O)](Z = Zn、Cd、Cr、Mn、Fe、Ni、Co、Cu)的过渡元素取代的磷钨系列杂多配合物,此系列化合物经过与修饰后的树脂负载后又制备了8种杂多配合物复合催化材料(简写为PW_9V_2Z/Resin)(Z = Zn、Cd、Cr、Mn、Fe、Ni、Co、Cu)。并利用红外光谱、紫外-可见吸收光谱、X射线粉末衍射、扫描电镜和X射线光电子能谱一系列分析手段对制备的16种杂多配合物催化材料剂进行了分析测定和表征。结果表明:所合成的过渡元素取代的系列杂多配合物仍然具有Keggin型结构;复合材料是通过Z-N配位键与修饰后的载体键合。
以罗丹明B为模拟有机染料污染物,采用合成的16种过渡元素取代的磷钨系列杂多配合物及其复合材料为光催化剂,通过改变光照时间、催化剂种类、催化剂浓度以及pH值等因素催化条件,进行了紫外光照射下对罗丹明B溶液的光催化降解进行了研究。研究结果表明:过渡元素取代的磷钨系列杂多配合物具有良好的催化活性,最高降解率达到92%;均相体系中,8种催化剂的催化效果均在80%以上;非均相体系中,在60min内,最高降解率达到70%。
With the fast industrial development, kinds of hazardous pollutants have entered environment. Especially the great increase of industrial wastewater that underlined the pollution in aqueous environment and jeopardized the environment critically. Due to their low concentration, stable structure, and being difficult to degrade biologically, some poisonous organic pollutants can hardly be removed by traditional method. Photocatalytic degradation, a new method of disposing wastewater developed in recent thirty years, features stable reaction, good degradation effect, and non-secondary pollution.
This paper synthesized eight phosphotungstic series of heteropoly complexes, which are substituted by the transition elements composing K_n[PW_9V_2O_(39)Z(H_2O)] (Z = Zn, Cd, Cr, Mn, Fe, Ni, Co, Cu). When such series of compounds and the modified sign are loaded, eight heteropoly complexes of compound catalytic materials (abbreviation as PW_9V_2Z/Resin) (Z = Zn, Cd, Cr, Mn, Fe, Ni, Co, Cu) were produced. In addition, we carried out analytical determination and characterization for the 16 heteropoly compound catalytic material agents by a series of analytical methods such as Infrared spectroscopy, UV - visible absorption spectroscopy, X-ray powder diffraction analysis, scanning electron microscopy and X-ray photoelectron spectroscopy. The results show that the synthesized heteropoly compound series remain as Keggin-type structure; Composite materials are bonded with the modified load through the Z-N coordination bond.
This paper studied photocatalytic degradation for Rhodamine B solution under UV irradiation on the condition that Rhodamine B is taken as model organic dye pollutants, which used synthetic 16 kinds phosphotungstic series of heteropoly complexes and composite materials as photocatalyst, by changing the illumination time, catalyst type, catalyst concentration and pH, and other factors catalytic conditions. The results show that phosphotungstic series of heteropoly compounds which are substituted by the transition elements have good catalytic activity, and the maximum degradation rate is up to 92%; the catalytic effects of eight kinds are more than 80% under homogeneous system; the maximum degradation rate is up to 70% in 60min under non-homogeneous system.
引文
[1]北京水环境技术与设备研究中心、北京市环境保护科学研究院、国家城市污染控制工程技术研究中心主编.三废处理工程技术手册(废水卷)[M].第1版.北京:化学工业出版社, 2000.
[2] Wu T X, Liu GM, Zhao JC, et al Photoassisted degradation of dye pollutants V: self photosensitized oxidative transfomation of RhB under visible light irradiation in aqueous TiO2 dispersion [J]. J Phys Chem, 1998, 102: 5845-5851.
[3] Zhao Jc, Wukq, Wu T X, et al Photodegradation of dyes with poor solubility in an aqueous surfactant/TiO2 dispersion under visible light irradiation [J]. J Chem Soc Faraday Trans, 1998, 94(5): 673-676.
[4]张天永,朱丹丹,崔新安.有机颜料的光催化降解及添加表面活性剂的影响[J].分子催化, 2003(03): 202-204.
[5] Rhule J. T., Hill C. L., Judd D. A., Schinazi R. F. Polyoxometalates in Medicine[J]. Chem. Rev. 1998. 98. 327~358.
[6] Wang K. Z., Gao L. H. Synthesis and Properties of Organic-Inorganic Hybrid Materials of (Me2NC6H4CH = CHC5H4NC4H9)7K3[P2Mo4W13MO62](M = Mn, Co, Ni, Cu, Zn)[J]. Synth. React. Inorg. Met-Org. Chem. 2003. 33(3). 469-480.
[7] Mizuno N., Misono M. Heterogeneous Catalysis[J]. Chem. Rev. 1998. 98. 199-218.
[8] Li D. F., Guo Y., Hu C. W., Li M., Wang E. B. Photocatalytic Degradation of Aqueous Formic Acid over the Silica Composite Films Based on Lacunary Keggin-Type Polyoxometalates[J]. Appl. Cat. A. 2002. 235. 11-20.
[9] Lei P. X., Chen C. C., Yang J., Ma W. H., Zhao J. C., Zang L. Degradation of Dye Pollutants by Immobilized Polyoxometalate with H2O2 under Visible-Light Irradiation[J]. Environ. Sci. Technol. 2005. 39(21). 8466-8474.
[10] Gkika E., Kormail P., Antonaraki S., Dimoticali D., Papaconstantinou E., Hiskia A. Polyoxometallates as Effective Photocatalysts in Water Purification from Pesticides[J]. Inter. J. Photoenergy. 2004.6(4).227-331.
[11] Hori H., Hayakawa E., Koike K., Einaga H., Ibusuki T. Decomposition of Nonafluoropentanoic Acid by Heteropolyacid Photocatalyst H3PW12O40 in Aqueous Solution[J]. J. Mol. Cat. A. 2004.211.35-41.
[12]胡长文,王思波.杂多酸的催化技术进展[J].现代化工, 1992, (4): 36-37.
[13] Li X. Z., Zhao W., Zhao J. C. Visible Light-Sensitized Semiconductor Photocatalytic Degradation of 2,4-Dichlorphenol[J]. Sci. China Ser. B. 2002. 45. 421-425.
[14]钱铭熙.催化剂中的新秀-杂多酸[J].现代化工, 1985, (4): 52-53.
[15]王恩波,李阳光,鹿颖,王新龙.多酸化学概论[M].东北师范大学出版社, 2009(7): 272-273.
[16] Li G, Gu Y, Ding Y, Zhang H, Wang J, Gao Q, Yan L and Suo J. Wells Dawson type molybdovanadophosphoric heteropolyacids catalyzed Prins cyclization of alkenes with paraformaldehyde under mild conditions-a facile and efficient method to 1,3-dioxane derivatives. J. Mol. Catal. A: Chem., 2004, 218: 147-152.
[17] Li G, Wang B, Wang J, Ding Y, Yan L and Suo J. Efficient and highly-selective cycloaddition of epoxides with carbonyl compound over Wells-Dawson type heteropolyacids. J. Mol. Catal.A: Chem., 2005, 236: 72-76.
[18]郭伊荇,东北师范大学博士学位论文[D].东北师范大学, 2001.
[19] Guo Y and Hu C. Heterogeneous photocatalysis by solid polyoxometalates. J. Mo. Catal. A: Chem. , 2007, 262: 136-147.
[20]杨宇,东北师范大学博士学位论文[D].东北师范大学, 2005.
[21] Guo Y, Wang Y, Hu C and Wang E. Microporous polyoxometalates POMs/SiO2: synthesis and photocatalytic degradation of aqueous organocholorine pesticides. Chem. Mater., 2000, 12: 3501-3507.
[22] Guo Y, Hu C, Wang X, Wang E, Zhou Y and Feng S. Microporous decatungstates: synthesis and photochemical behavior. Chem. Mater., 2001, 13: 4058-4064.
[23] Guo Y, Hu C, Jiang S, Guo C, Yang Y and Wang E. Heterogeneous photodegradation of aqueous hudroxy butanedioic acid by microporous polyoxometalates. Appl. Catal. B, 2002, 36: 9-17.
[24] Guo Y, Li D, Hu C, Wang Y and Wang E. Photocatalytic degradation of aqueous organocholorine pesticide on the layered double hydroxide pillared by paratungstate aion, Mg12Al6(OH)36(W7O24)·4H2O. Appl. Catal. B, 2001, 30: 337-349.
[25] Guo Y, Hu C, Jiang C, Yang Y, Jiang S, Li X and Wang E. Preparation and heterogeneous photocatalytic behaviors of the surface-modified porous silica materials impregnated with monosubstituted Keggin units. J. Catal., 2003, 217: 141-151.
[26] Yang Y, Guo Y, Hu C, Jiang C and Wang E. Synergistic effect of Keggin-type[X~(n+)W_(11)O_(39)]~((12-n))- and TiO_2 in macroporous hybrid materials [X~n+W_(11)O_(39)]_((12-n))~-—TiO_2 for the photocatalytic degradation of textile dyes. J. Mater. Chem., 2003, 13: 1686—1694.
[27] Yang Y, Guo, Y Hu C, Wang Y and Wang E. Preparation of surface modifications of mesoporous titania with monosubstituted Keegin units and their catalytic performance for organochlorine pesticide and dyes under UV irradiation. Appl. Catal. A, 2004. 273: 201-210.
[28] Yang Y, Wu Q, Guo Y, Hu C and Wang E. Efficient degradation of dye pollutants on nanoporous polyxotungstate anatase composite under visible-light irradiation. J. Mol. Catal. A, 2005, 225: 203-212.
[29] Brent Smith. Decolorizing Dye Wastewater Using Chitosan [J]. American Dyestuff Report. 1993, 10: 18-36.
[30]陈亮,陈东辉,李步祥.壳聚糖吸附处理废水的研究进展[J].四川环境, 2001, 20(3): 19-23.
[31]许昭怡,张慧春.大孔树脂吸附萘系染料中间体生产废水的进展[J].化工环保, 1999, 19(1): 20-24.
[32]戴猷元,张瑾.有机废水萃取处理技术[M].修订版.北京:化学工业出版社, 2006.
[33]吴开芬.用超滤法处理靛蓝废水[J].增刊.环境科学进展, 1998, 6: 124-127.
[34]孙巍,李真,吴松海等.磁分离技术在污水处理中的应用[J].磁性材料及器件, 2006, 8: 6-10.
[35]修艳华,李贞玉,李长海.络合萃取技术处理CLT酸废水[J].长春工业大学学报(自然科学版). 2005, 26(2): 96-98.
[36]沈澄英.活性染料废水混凝处理研究[J].安徽化工, 2005, 135(3): 49-50.
[37]闫庆松.厌氧+好氧+煤渣吸附处理偶氮染料废水的研究[J].工业水处理, 2000, 7: 15-18.
[38]刘兴旺,戴友芝.厌氧生物法处理活性染料废水的研究[J].湘潭大学自然科学学报. 2005, 27(2): 116-119.
[39]许怡,杜国勇,赵立志.生物法处理废水的现状与展望[J].环保技术. 2004, 22(6): 40-43.
[40] Rhule J. T., Hill C. L., Judd D. A., Schinazi R. F. Polyoxometalates in Medicine[J]. Chem. Rev.1998. 98: 327-358.
[41] Coronado E., Gomez-Garcia C. J. Polyoxometalate-Based Molecular Materials [J]. Chem. Rev. 1998. 98: 273-296.
[42]高丽华,王科志.具有Keggin和Dawson结构的钨钼杂多阴离子的有机衍生物及其应用[J].化学通报. 1993. 12: 40-43.
[43] Xiang H., Gao L. H., Wang K. Z, Wang Z. W., Li Z., Huang W. T., Yang H., Gong Q. H. Ultrafast Third-Order Nonlinear Optical Response of Organic-Inorganic Hybrid Materials(C19H25N2)7Hn[P2Mo18-nVnO62][J]. Chin. Phys. Lett. 2003. 20(10). 1759-1762.
[44] Gao L. H., Wang K. Z. Hybrid Self-Assembled Multilayer Film Formde by Alternating Layers of Keggin Polyoxometalates and 1,10-DAD [J]. Chin. Chem. Lett. 2003. 14(5): 513-514.
[45] Mizuno N., Misono M. Heterogeneous Catalysis [J]. Chem. Rev. 1998. 8: 199-218.
[46] Mylonas A., Papaconstantinou E. On the Mechanism of Photocatalytic Degradation of Chlorinated Phenols to CO2 and HCl by Polyoxometalates [J]. J. Photochem.Photobiol. A: Chem. 1996. 94: 77-82.
[47] Mylonas A., Hiskia A., Papaconstantinou E. Contribution to Water Purification Using Polyoxometalates. Aromatic Derivatives, Chloroacetic Acids [J]. J. Mol. Catal. A. 1996. 114: 191-200.
[48] Hiskia A., Ecke M., Troupis A., Kokorakis A., Hennig H., Papaconstantinou E. Sonolytic, Photolytic, and Photocatalytic Decomposition of Atrazine in the Presence of Polyoxometalates [J]. Environ. Sci. Technol. 2001.35. 2358-2364.
[49] Ozer R.R., Ferry J.L. Photocatalytic Oxidation of Aqueous 1,2-Dichlorobenzene by Polyoxometalates Supported on the NaY Zeolite [J]. J. Phys. Chem. B. 2002. 106: 4336-4342.
[50]王恩波,胡长文,许林.多酸化学导论[M] .北京:化学工业出版社, 1998.