胺功能化MIL-101(Cr)@SiO_2@Fe_3O_4催化剂及其Knoevenagel反应性能
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摘要
采用溶剂热法在纳米SiO_2@Fe_3O_4磁性颗粒表面原位合成MIL-101(Cr),制备磁性MIL-101(Cr)@SiO_2@Fe_3O_4催化剂。采用甲胺、乙二胺和丁二胺对制备的磁性催化剂进行功能化,得到胺功能化NH2-MIL-101(Cr)@SiO_2@Fe_3O_4催化剂。利用XRD、FT-IR、BET、SEM、TEM和VSM等对催化剂结构进行表征,评价胺功能化NH2-MIL-101(Cr)@SiO_2@Fe_3O_4催化剂对糠醛和氰乙酸乙酯Knoevenagel缩合反应性能和重复使用性能,考察反应条件与催化性能的关系。结果表明,制备的新型胺功能化NH2-MIL-101(Cr)@SiO_2@Fe_3O_4催化剂具有MIL-101(Cr)的结构特征和良好的超顺磁性能,对糠醛和氰乙酸乙酯Knoevenagel缩合反应表现出很好的催化性能,其中,乙二胺功能化30%MIL-101(Cr)@SiO_2@Fe_3O_4催化剂对Knoevenagel缩合反应的性能最佳,在反应温度40℃和反应时间1 h条件下,氰乙酸乙酯转化率为97. 0%,产物选择性接近100%。反应后磁性催化剂可以通过外磁场容易进行分离,重复使用5次,氰乙酸乙酯转化率仍大于93%。
The magnetically MIL-101(Cr)@SiO_2@Fe_3O_4 catalysts with different MIL-101(Cr) contents were synthesized using in situ method of encapsulating MIL-101(Cr) on magneticSiO_2@Fe_3O_4 nanoparticles surface. Then methylamine,ethylenediamine and butanediamine were used as functional groups for MIL-101(Cr)@SiO_2@Fe_3O_4 and novel NH2-MIL-101(Cr)@ SiO_2@Fe_3O_4 catalysts were prepared. Structure of the catalysts was characterized by XRD,FT-IR,BET,SEM,TEM and VSM techniques. Catalytic performance and recovery properties of the catalysts for the Knoevenagel reaction of furfural with ethyl cyanoacetate were evaluated. The relationship of reaction conditions and catalytic perform-ance were also investigated. The results showed that all three amines functionalized catalysts had the structure of MIL-101(Cr) and good superparamagnetism. The magnetic NH_2-MIL-101(Cr)@ SiO_2@Fe_3O_4 catalysts exhibited well catalytic performance for the Knoevenagel reaction of furfural with ethyl cyanoacetate. Among them,the 30% MIL-101(Cr)@SiO_2@Fe_3O_4 catalyst was the best one. Conversion of ethyl cyanoacetate could reach 97. 0% and selectivity of product could reach ～ 100% at reaction temperature of40 ℃ and 1 h reaction time. After reaction,the catalysts could be easily separated from the reaction mixture by an external magnet. The recovery catalyst could be reused for five times,and conversion of ethyl cyanoacetate kept over 93%.
The magnetically MIL-101(Cr)@SiO_2@Fe_3O_4 catalysts with different MIL-101(Cr) contents were synthesized using in situ method of encapsulating MIL-101(Cr) on magneticSiO_2@Fe_3O_4 nanoparticles surface. Then methylamine,ethylenediamine and butanediamine were used as functional groups for MIL-101(Cr)@SiO_2@Fe_3O_4 and novel NH2-MIL-101(Cr)@ SiO_2@Fe_3O_4 catalysts were prepared. Structure of the catalysts was characterized by XRD,FT-IR,BET,SEM,TEM and VSM techniques. Catalytic performance and recovery properties of the catalysts for the Knoevenagel reaction of furfural with ethyl cyanoacetate were evaluated. The relationship of reaction conditions and catalytic perform-ance were also investigated. The results showed that all three amines functionalized catalysts had the structure of MIL-101(Cr) and good superparamagnetism. The magnetic NH_2-MIL-101(Cr)@ SiO_2@Fe_3O_4 catalysts exhibited well catalytic performance for the Knoevenagel reaction of furfural with ethyl cyanoacetate. Among them,the 30% MIL-101(Cr)@SiO_2@Fe_3O_4 catalyst was the best one. Conversion of ethyl cyanoacetate could reach 97. 0% and selectivity of product could reach ～ 100% at reaction temperature of40 ℃ and 1 h reaction time. After reaction,the catalysts could be easily separated from the reaction mixture by an external magnet. The recovery catalyst could be reused for five times,and conversion of ethyl cyanoacetate kept over 93%.
引文
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[22]Liu Hongfei,Ji Shengfu,Zheng Yi,et al. Porous Ti O2-coated magnetic core-shell nanocomposites:preparation and enhanced photocatalytic activity[J]. Chinese Journal of Chemical Engineering,2013,21(5):569-576.
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[24]Jiang Sai,Yan Junlei,Habimana F,et al. Preparation of magnetically recyclable MIL-53(Al)@Si O2@Fe3O4catalysts and their catalytic performance for Friedel-Crafts acylation reaction[J]. Catalysis Today,2016,264:83-90.
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[26]Liang Z J,Marshall M,Ng C H,et al. Comparison of conventional and HF-free-synthesized MIL-101 for CO2adsorption separation and their water stabilities[J]. Energy&Fuels,2013,27(12):7612-7618.
[27]Kim S N,Yang S T,Kim J,et al. Post-synthesis functionalization of MIL-101 using diethylenetriamine:a study on adsorption and catalysis[J]. Cryst Eng Comm,2012,14(12):4142-4147.
[28]Kasinathan P,Seo Y K,Shim K E,et al. Effect of diamine in amine-functionalized MIL-101 for Knoevenagelcondensation[J]. Bulletin of the Korean Chemical Society,2011,32(6):2073-2075.
[29]Liu Hongfei,Ji Shengfu,Zheng Yuanyuan,et al. Modified solvothermal synthesis of magnetic microspheres with multifunctional surfactant cetyltrimethyl ammonium bromide and directly coated mesoporous shell[J]. Powder Technology,2013,246:520-529.
[30]Deng Yonghui,Qi Dawei,Deng Chunhui,et al. Superparamagnetic high-magnetization microspheres with an Fe3O4@Si O2Core and perpendicularly aligned mesoporous Si O2shell for removal of microcystins[J]. Journal of the American Chemical Society,2008,130(1):28-29
[31]Férey G,Mellot-Draznieks C,Serre C,et al. A chromium terephthalate-based solid with unusually large pore volumes and surface area[J]. Science,2005,309(5743):2040-2042.
[32]Li Qingyuan,Jiang Sai,Ji Shengfu,et al. Synthesis of magnetically recyclable MOF-5@Si O2@Fe3O4catalysts and their catalytic performance of Friedel-Crafts alkylation[J]. Journal of Porous Materials,2015,22(5):1205-1214.
[33]Liu Hongfei,Jia Zhigang,Shengfu Ji,et al. Synthesis of Ti O2/Si O2@Fe3O4magnetic microspheres and their properties of photocatalytic degradation dyestuff[J]. Catalysis Today,2011,175(1):293-298.
[34]Opanasenko M,Dhakshinamoorthy A,Shamzhy M,et al.Comparison of the catalytic activity of MOFs and zeolites in Knoevenagel condensation[J]. Catalysis Science&Technology,2013,3(2):500-507.
[35]Hartmann M,Fischer M. Amino-functionalized basic catalysts with MIL-101 structure[J]. Microporous and Mesoporous Materials,2012,164(15):38-43.
[36]Burgoyne A R,Meijboom R. Knoevenagel condensation reactions catalysed by metal-organic frameworks[J].Catalysis Letters,2013,143(6):563-571.
[37]Li Qingyuan,Jiang Sai,Ji Shengfu,et al. Synthesis of magnetically recyclable ZIF-8@Si O2@Fe3O4catalysts and their catalytic performance for Knoevenagel reaction[J].Journal of Solid State Chemistry,2015,223(14):65-72.
[38]Xamena F X L,Cirujano F G,Corma A. An unexpected bifunctional acid base catalysis in IRMOF-3 for Knoevenagel condensation reactions[J]. Microporous and Mesoporous Materials,2012,157(27):112-117.
[39]Ravon U,Savonnet M,Aguado S,et al. Engineering of coordination polymers for shape selective alkylation of large aromatics and the role of defects[J]. Microporous and Mesoporous Materials,2010,129(3):319-329.
[40]Juan-Alca1iz J,Ramos-Fernandez E V,Lafont U,et al.Building MOF bottles around phosphotungstic acid ships:one-pot synthesis of bi-functional polyoxometalate-MIL-101 catalysts[J]. Journal of Catalysis,2010,269(1):229-241.
[41]Corma A,Iborra S,Sanchez F. Immobilized proton sponge on inorganic carriers:the synergic effect of the support on catalytic activity[J]. Journal of Catalysis,2002,211(1):208-215.
[42]Neogi S,Sharma M K,Bharadwaj P K. Knoevenagel condensation and cyanosilylation reactions catalyzed by a MOF containing coordinatively unsaturated Zn(Ⅱ)centers[J].Journal of Molecular Catalysis A:Chemical,2009,299(1):1-4.
[43]Nguyen L T L,Le K K A,Truong H X,et al. Metal-organic frameworks for catalysis:the Knoevenagel reaction using zeolite imidazolate framework ZIF-9 as an efficient heterogeneous catalyst[J]. Catalysis Science&Technology,2012,2(3):521-528.
[2]Li Yiqun. Potassium phosphate as a catalyst for the Knoevenagel condensation[J]. Journal of Chemical Research,2000,2000(11):524-525.
[3]Kumbhare R M,Sridhar M. Magnesium fluoride catalyzed Knoevenagel reaction:an efficient synthesis of electrophilic alkenes[J]. Catalysis Communications,2008,9(3):403-405.
[4]Xue Bing,Zhu Jiagui,Liu Na,et al. Facile functionalization of graphene oxide with ethylenediamine as a solid base catalyst for Knoevenagel condensation reaction[J]. Catalysis Communications,2015,64:105-109.
[5]Khan F A,Dash J,Satapathy R,et al. Hydrotalcite catalysis in ionic liquid medium:a recyclable reaction system for heterogeneous Knoevenagel and nitroaldol condensation[J].Tetrahedron Letters,2004,45(15):3055-3058.
[6]Linares C F,Goldwasser M R,Machado F J,et al. Advantages of base exchanged natural clinoptilolite as a catalyst for the Knoevenagel reaction[J]. Microporous and Mesoporous Materials,2000,41(1):69-77.
[7]Zhang Wenfei,Liang Jinhua,Liu Yanqiu,et al. Knoevenagel condensation reaction over acid-base bifunctional MgO/HMCM-22 catalysts[J]. Chinese Journal of Catalysis,2013,34(3):559-566.
[8]Dhakshinamoorthy A,Opanasenko M,ejka J,et al. Metal organic frameworks as solid catalysts in condensation reactions of carbonyl groups[J]. Advanced Synthesis&Catalysis,2013,355(2/3):247-268.
[9]梁倩,赵震.金属有机骨架材料储存CO2的研究进展[J].工业催化,2010,18(7):1-7.Liang Qian,Zhao Zhen. Research progress in metal-organic frameworks materials for CO2storage[J]. Industrial Catalysis,2010,18(7):1-7.
[10]Valvekens P,andichel M,Waroquier M,et al. Metal-dioxidoterephthalate MOFs of the MOF-74 type:microporous basic catalysts with well-defined active sites[J]. Journal of Catalysis,2014,317:1-10.
[11]Luo Qunxing,Song Xuedan,Ji Min,et al. Molecular sizeand shape-selective Knoevenagel condensation over microporous Cu3(BTC)2immobilized amino-functionalized basic ionic liquid catalyst[J]. Applied Catalysis A:General,2014,478(5):81-90.
[12]Gascon J,Aktay U,Hernandez-Alonso M D,et al. Aminobased metal-organic frameworks as stable,highly active basic catalysts[J]. Journal of Catalysis,2009,261(1):75-87.
[13]Cortese R,Duca D. A DFT study of IRMOF-3 catalysed Knoevenagel condensation[J]. Physical Chemistry Chemical Physics,2011,13(35):15995-16004.
[14]Serra-Crespo P,Ramos-Fernandez E V,Gascon J,et al.Synthesis and characterization of an amino functionalized MIL-101(Al):separation and catalytic properties[J].Chemistry of Materials,2011,23(10):2565-2572.
[15]Srirambalaji R,Hong S,Natarajan R,et al. Tandem catalysis with a bifunctional site-isolated Lewis acid-Brnsted base metal-organic framework,NH2-MIL-101(Al)[J].Chemical Communications,2012,48(95):11650-11652.
[16]Wang Dengke,Li Zhaohui. Bi-functional NH2-MIL-101(Fe)for one-pot tandem photo-oxidation/Knoevenagel condensation between aromatic alcohols and active methylene compounds[J]. Catalysis Science&Technology,2015,5(3):1623-1628.
[17]Yang Yang,Yao Hongfei,Xi Fugui,et al. Amino-functionalized Zr(IV)metal-organic framework as bifunctional acid-base catalyst for Knoevenagel condensation[J]. Journal of Molecular Catalysis A:Chemical,2014,390(8):198-205.
[18]Hwang Y K,Hong D Y,Chang J S,et al. Amine grafting on coordinatively unsaturated metal centers of MOFs:consequences for catalysis and metal encapsulation[J]. Angewandte Chemie International Edition,2008,47(22):4144-4148.
[19]刘会君,蓝国钧,颜宇,等.一步直接水热法合成高铁含量新型磁性有序介孔纳米复合材料[J].工业催化,2011,19(8):11-15.Liu Huijun,Lan Guojun,Yan Yu,et al. Direct hydrothermal synthesis of novel ordered magnetic mesoporous nanocomposites with high content of iron[J]. Industrial Catalysis,2011,19(8):11-15.
[20]崔进,赵景联,李厚宝,等.磁性纳米Ti O2/Si O2/Fe3O4光催化剂的制备及光催化性能研究[J].工业催化,2009,17(5):27-31.Cui Jin,Zhao Jinlian,Li Houbao,et al. Preparation and photocatalytic properties of magnetic nanoszied Ti O2/Si O2/Fe3O4photocatalyst[J]. Industrial Catalysis,2009,17(5):27-31.
[21]Ji Junhong,Zeng Penghui,Ji Shengfu,et al. Catalytic activity of core-shell structured Cu/Fe3O4@Si O2microsphere catalysts[J]. Catalysis Today,2010,158(3):305-309.
[22]Liu Hongfei,Ji Shengfu,Zheng Yi,et al. Porous Ti O2-coated magnetic core-shell nanocomposites:preparation and enhanced photocatalytic activity[J]. Chinese Journal of Chemical Engineering,2013,21(5):569-576.
[23]Li Qingyuan,Jiang Sai,Ji Shengfu,et al. Magnetically recyclable Cu-BTC@Si O2@Fe3O4catalysts and their catalytic performance for the pechmann reaction[J]. Industrial&Engineering Chemistry Research,2014,53(39):14948-14955.
[24]Jiang Sai,Yan Junlei,Habimana F,et al. Preparation of magnetically recyclable MIL-53(Al)@Si O2@Fe3O4catalysts and their catalytic performance for Friedel-Crafts acylation reaction[J]. Catalysis Today,2016,264:83-90.
[25]Liu Hongfei,Ji Shengfu,Yang Hao,et al. Ultrasonic-assisted ultra-rapid synthesis of monodisperse meso-Si O2@Fe3O4microspheres with enhanced mesoporous structure[J]. Ultrasonics Sonochemistry,2014,21(2):505-512.
[26]Liang Z J,Marshall M,Ng C H,et al. Comparison of conventional and HF-free-synthesized MIL-101 for CO2adsorption separation and their water stabilities[J]. Energy&Fuels,2013,27(12):7612-7618.
[27]Kim S N,Yang S T,Kim J,et al. Post-synthesis functionalization of MIL-101 using diethylenetriamine:a study on adsorption and catalysis[J]. Cryst Eng Comm,2012,14(12):4142-4147.
[28]Kasinathan P,Seo Y K,Shim K E,et al. Effect of diamine in amine-functionalized MIL-101 for Knoevenagelcondensation[J]. Bulletin of the Korean Chemical Society,2011,32(6):2073-2075.
[29]Liu Hongfei,Ji Shengfu,Zheng Yuanyuan,et al. Modified solvothermal synthesis of magnetic microspheres with multifunctional surfactant cetyltrimethyl ammonium bromide and directly coated mesoporous shell[J]. Powder Technology,2013,246:520-529.
[30]Deng Yonghui,Qi Dawei,Deng Chunhui,et al. Superparamagnetic high-magnetization microspheres with an Fe3O4@Si O2Core and perpendicularly aligned mesoporous Si O2shell for removal of microcystins[J]. Journal of the American Chemical Society,2008,130(1):28-29
[31]Férey G,Mellot-Draznieks C,Serre C,et al. A chromium terephthalate-based solid with unusually large pore volumes and surface area[J]. Science,2005,309(5743):2040-2042.
[32]Li Qingyuan,Jiang Sai,Ji Shengfu,et al. Synthesis of magnetically recyclable MOF-5@Si O2@Fe3O4catalysts and their catalytic performance of Friedel-Crafts alkylation[J]. Journal of Porous Materials,2015,22(5):1205-1214.
[33]Liu Hongfei,Jia Zhigang,Shengfu Ji,et al. Synthesis of Ti O2/Si O2@Fe3O4magnetic microspheres and their properties of photocatalytic degradation dyestuff[J]. Catalysis Today,2011,175(1):293-298.
[34]Opanasenko M,Dhakshinamoorthy A,Shamzhy M,et al.Comparison of the catalytic activity of MOFs and zeolites in Knoevenagel condensation[J]. Catalysis Science&Technology,2013,3(2):500-507.
[35]Hartmann M,Fischer M. Amino-functionalized basic catalysts with MIL-101 structure[J]. Microporous and Mesoporous Materials,2012,164(15):38-43.
[36]Burgoyne A R,Meijboom R. Knoevenagel condensation reactions catalysed by metal-organic frameworks[J].Catalysis Letters,2013,143(6):563-571.
[37]Li Qingyuan,Jiang Sai,Ji Shengfu,et al. Synthesis of magnetically recyclable ZIF-8@Si O2@Fe3O4catalysts and their catalytic performance for Knoevenagel reaction[J].Journal of Solid State Chemistry,2015,223(14):65-72.
[38]Xamena F X L,Cirujano F G,Corma A. An unexpected bifunctional acid base catalysis in IRMOF-3 for Knoevenagel condensation reactions[J]. Microporous and Mesoporous Materials,2012,157(27):112-117.
[39]Ravon U,Savonnet M,Aguado S,et al. Engineering of coordination polymers for shape selective alkylation of large aromatics and the role of defects[J]. Microporous and Mesoporous Materials,2010,129(3):319-329.
[40]Juan-Alca1iz J,Ramos-Fernandez E V,Lafont U,et al.Building MOF bottles around phosphotungstic acid ships:one-pot synthesis of bi-functional polyoxometalate-MIL-101 catalysts[J]. Journal of Catalysis,2010,269(1):229-241.
[41]Corma A,Iborra S,Sanchez F. Immobilized proton sponge on inorganic carriers:the synergic effect of the support on catalytic activity[J]. Journal of Catalysis,2002,211(1):208-215.
[42]Neogi S,Sharma M K,Bharadwaj P K. Knoevenagel condensation and cyanosilylation reactions catalyzed by a MOF containing coordinatively unsaturated Zn(Ⅱ)centers[J].Journal of Molecular Catalysis A:Chemical,2009,299(1):1-4.
[43]Nguyen L T L,Le K K A,Truong H X,et al. Metal-organic frameworks for catalysis:the Knoevenagel reaction using zeolite imidazolate framework ZIF-9 as an efficient heterogeneous catalyst[J]. Catalysis Science&Technology,2012,2(3):521-528.