采用元素分析和红外光谱对所制磷钨酸1,3-二乙酸咪唑盐催化剂进行表征，考察了光照时间、催化剂用量对光催化降解有机染料甲基红效率的影响. 结果表明，无光催化剂时甲基红可直接光解，完全光解所需时间为220 min；催化剂用量为0.02?0.10 g时，对甲基红光降解效率随催化剂用量增加显著提高；加入0.08 g催化剂后，紫外光照射60 min可使甲基红溶液降解完全，降解效率为未加入催化剂时的3倍.
As the increase of environmental pollution and awareness of environmental protection, green chemistry is one of important direction of modern science. In recent years, heteropolyacids have been used as an efficient photocatalyst for the removal of organic pollutants. Ionic liquids have been applied in organic synthesis, electrochemistry, separation purification, and materials science because of their unique physical and chemical properties. The polyoxometalate-based ionic liquid hybrid material is a novel green catalyst containing the typical Keggin structure of heteropolyacids and ionic liquid cations, which possesses good water resistance, acidity, and is potential for efficient reaction from separation properties. Based on a model compound, organic dye methyl red (MR), the photocatalytic ability of the solid phase catalyst 1,3-bis(carboxymethyl)-imidazolium phosphotungstate was studied under UV light irradiation. The prepared catalyst was characterized by elemental analysis and IR spectra. The effects of irradiation time of UV light and amount of the catalyst to the degradation efficiency were investigated. The results showed that the synthesis photocatalyst retains both the Keggin structure of phosphotungstic anion and the structure of imidazolium cation. MR can undergo direct photolysis and the time required for complete photolysis was 220 min in the absence of the catalyst. When the amount of the catalyst was 0.02?0.10 g, the degradation efficiency of MR increased significantly with the increasing of the catalyst amount. The total degradation time of MR was 60 min when 0.08 g catalyst was added under UV light irradiation, and its degradation efficiency can reach three times as much as when no catalyst was added. The synthesized solid phase catalyst exhibited higher catalytic activity and good water resistance in the photolysis reactions. In addition, the catalyst was very stable and easily separated from the reaction system for recycling. It overcame the defects of traditional acid catalysts, which provided a promising new idea for high atom economy and green route of photocatalytic reactions.
[1] 王伟平，张义军，杨水金.杂多酸光催化降解染料废水的研究进展[J].化工文摘, 2009, ,(4):52-55
[2]Wang W P, Zhang Y J, Yang S J.Progresses on the Study of Photodegradation of Dye Wastewaters by Heteropoly Acid[J].China Chemicals, 2009, ,(4):52-55
[3]罗洁，陈建山.光催化氧化降解印染废水的研究[J].工业催化, 2004, 12(6):36-38
[4]Luo J, Chen J S.Photocatalytic oxidative degradation of dye printing wastewatercatalyzed by titania[J].Industrial Catalysis, 2004, 12(6):36-38
[5] 廖玉超，蔡铁军.杂多酸化合物光催化剂研究新进展[J].湘潭师范学院学报(自然科学版), 2006, ,(2):73-77
[6]Liao Y C, Cai T J.[J].Journal of Xiangtan Normal University(Natural Science Edition), 2006, ,(2):73-77
[7] 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: 171.
[8]Wang E B, Hu C W, Xu Lin.Introduction to Polyacid Chemistry [M]. Beijing, Chemical Industry Press, 1998:171.
[9]Heydari A, Shiroodi R K, Hamadi H, et al.N-tert-Butoxycarbonylation of Amines Using H3PW12O40 as anEfficient Heterogeneous and Recyclable Catalyst[J].Tetrahedron Lett., 2007, 48(33):5865-5868
[10]Chakrabarty M, Mukherji A, Mukherjee R, et al.A KegginHeteropoly Acid as an Efficient Catalyst for an Expeditious,One-pot Synthesis of 1-Methyl-2-(hetero)arylbenzimidazoles[J].Tetrahedron Lett., 2007, 48(30):5239-5242
[11]Hiskia A, Mylonas A, Papaconstantinou E.Comparison of thePhotoredox Properties of Polyoxometallates and SemiconductingParticles[J].Chem. Soc. Rev., 2001, 30(1):62-69
[12]邓佩佩，郑占伟，蔡喜田，等.磷钨酸光催化降解有机污染物的研究现状[J].河北化工, 2012, 35(2):53-55
[13]Deng P P, Zhen Z w, Cai X T.Research Status on Photocatalytic Degradation by Phosphotungstic acid for Organic Pollutants[J].Hebei Hua gong, 2012, 35(2):53-55
[14]宁建梅，彭坤，杨丽霞，等.杂多酸型离子液体的合成及在清洁氧化中的应用[J].石油化工高等学校学报, 2015, 28(6):14-19
[15]Ning J M, Peng K, Yang L X.Synthesis of HeteroplyacidInioc Liquids and Their Application in Clean Oxidation[J].Journal of Petrochemical Universities, 2015, 28(6):14-19
[16] Liu Y Y, Xiao W W, Xia S Q, et al.SO3H-functionalizedacidic ionic liquids as catalysts for the hydrolusis of cellulose[J].Carbohydrate Polymers., 2013, ,(92):218-222
[17] 王一涛.功能化杂多酸型离子液体的合成、表征及催化性能研究[D].河南: 河南大学, 2015: 22.
[18]Wang Y T.Study on synthesis Charaterization and Catalytic Properties and Funcationalized Heteropolyanion-based Ionic Liquids[D]. Henan: Henan University, 2015: 22.
[19]付霓虹，袁玉国，王景芸，等.酸性离子液体催化降解纤维素的研究[J].应用化工, 2016, 45(5):908-911
[20]Fu N H, Yuan Y G, Wang J Y, eal.Cellulose degradation catalyzed by acid ionic liquids[J].Applied Chemical Industry, 2016, 45(5):908-911
[21]Fei Z F,Zhao D B.Bronsted acidic ionic liquids and their zwitterions: synthesis, characterization and pKa determination[J]. Chem. Eur. J., 2004, 10: 4886-4893.[J].Chem. Eur. J., 2004, ,(10):4886-4893
[22]王轶博，侯跃，高丽华，等.磷钼钒杂多酸的合成及其对染料废水的光催化降解性能[J].过程工程学报, 2015, 15(4):703-707
[23]Wang Y B, HouY, Gao L H.[J].The Chinese Journal of Process Engineering, 2015, 15(4):703-707
[24]甘雨，刘霞.杂多酸光催化降解有机污染物研究进展[J].科技导报, 2009, 27(9):92-96
[25]Gan Y, Liu X.Research Progress on Photocatalytic Degradation of Organic Pollutants by Heteropoly Catalysts[J].Ke Ji Dao Bao, 2009, 27(9):92-96
