有序介孔Ru-MgZr复合氧化物合成及催化亚油酸异构化性能

doi:10.11944/j.issn.1000-0518.2018.11.170412

摘要/Abstract

摘要：

筛选高效、高选择性多相催化剂异构化亚油酸是共轭亚油酸(CLA)研究的重点。本文采用溶剂挥发自组装改进的溶胶-凝胶法,合成有序介孔Ru掺杂的MgO-ZrO₂固体碱催化剂。考察了催化剂中不同Mg物质的量对催化剂孔径、比表面积和表面碱性以及Ru等的结构和性能对催化性能的影响。对比了催化剂的形貌、表面碱性及Ru组分对催化性能的影响程度。结果表明,n(Zr)∶n(Mg)=3∶1时,Ru掺杂的MgO-ZrO₂固体碱催化剂具有高度有序的介孔结构和高的比表面积。而n(Zr)∶n(Mg)=1∶1时, MgO-ZrO₂固体碱催化剂合成CLA产率较高,反应时间4 h,产率达到85%,催化效率为0.099 g(CLA)·L^-1(solvent)·min^-1,并且催化产物主要为具有生物活性的3种共轭亚油酸异构体。催化剂的强碱性位点和晶格Ru是催化异构化反应的两个活性位点,强碱性位点是提高催化性能的关键。固体碱复合氧化物催化效率高、制备方法简单、反应产物生物活性高等优点,具有较好的应用前景。

关键词: 有序介孔, 异构化反应, 共轭亚油酸

Abstract:

The preparation of highly efficient and selective catalyst is important for the isomerization of linoleic acid. Herein, ordered mesoporous Ru-MgO-ZrO₂ solid base catalysts were synthesized through the evaporation-induced self-assembly sol-gel method. The effects of the basicity, pore size and specific surface area of the catalyst were investigated. The effect of catalysts surface basicity, Ru doping and its effect on catalysis activity were also investigated. The results show that the Ru-MgO-ZrO₂ catalyst with n(Zr)∶n(Mg)=3∶1 has good order and high specific surface area. The strong base sites and lattice Ru of catalyst are the two active sites of catalytic reaction. The Ru-MgO-ZrO₂ catalyst with n(Zr)∶n(Mg)=1∶1 catalyst leads to the highest 85% yield of conjugated linoleic acid(CLA) in 4 hour reaction time and the productivity of CLA is 0.099 g(CLA)·L^-1(solvent)·min^-1. Furthermore, the products are mainly three kinds of isomers with biological activity. These solid base oxide catalysts with the advantages of high catalytic efficiency, simple preparation and high selectivity toward biological activity of linoleic acid products show application prospect.

Key words: ordered mesoporous, isomerization, conjugated linoleic acid

陈杰博,谢伟杰,王璐,王祎铭,雷玉凤,魏雅丽. 有序介孔Ru-MgZr复合氧化物合成及催化亚油酸异构化性能[J]. 应用化学, 2018, 35(11): 1342-1350.

CHEN Jiebo,XIE Weijie,WANG Lu,WANG Yiming,LEI Yufeng,WEI Yali. Synthesis of Ordered Mesoporous Ru-MgZr Composite Oxide Catalysts for Isomerization of Linoleic Acid[J]. Chinese Journal of Applied Chemistry, 2018, 35(11): 1342-1350.

参考文献

[1]	Yang B,Chen H Q,Stanton C,et al. Review of the Roles of Conjugated Linoleic Acid in Health and Disease[J]. J Funct Foods,2015,15(1):314-325.
[2]	Philoppaerts A,Goossens S,Vermandel W,et al. Design of Ru-zeolites for Hydrogen-free Production of Conjugated Linoleic Acids[J]. ChemSusChem,2011,4(6):757-767.
[3]	Bernas A,Murzin D Y.Linoleic Acid Isomerization on Ru/Al2O3 Catalyst:1.Conjugation and Hydrogenation[J]. Chem Eng J,2005,115(1/2):13-22.
[4]	Bernas A,Murzin D Y.Linoleic Acid Isomerization on Ru/Al2O3 Catalyst:2.Elementary Step Mechanism[J]. Chem Eng J,2005,115(1/2):23-43.
[5]	Bernas A,Kumar N,Laukkanen P,et al. Influence of Ruthenium Precursor on Catalytic Activity of Ru/Al2O3 Catalyst in Selective Isomerization of Linoleic Acid to Cis-9,Trans-11 and Trans-10,Cis-12 Conjugated Linoleic Acid[J]. Appl Catal A,2004,267(1/2):121-133.
[6]	Kreich M,Claus P.Direct Conversion of Linoleic Acid over Silver Catalyst in the Presence of H2:An Unusual Way Toward Conjugated Linoleic Acid[J]. Angew Chem Int Ed,2005,44(47):7800-7804.
[7]	Bernas A,Kumar N,Maki-Arvela P,et al. Heterogeneous Catalytic Production of Conjugated Linoleic Acid[J]. Org Proc Res Dev,2004,8(3):341-352.
[8]	Yasu-eda T,Kitamura S,Ikenaga N O,et al. Selective Oxidation of Alcohols with Molecular Oxygen over Ru/CaO-ZrO2[J]. J Mol Catal A-Chem,2010,323(1/2):7-15.
[9]	Tian X K,Zeng Y L,Xiao T,et al. Fabrication and Stabilization of Nanocrystalline Ordered Mesoporous MgO-ZrO2 Solid Solution[J]. Micropor Mesopor Mater,2011,143(2/3):357-361.
[10]	Sebedio J L,Christie W E,Adlof O R. Advances in Conjugated Linoleic Acid Research[M].Vol.2,AOCS Press,Champaign,2003:5-6.
[11]	Liu S G,Ma J,Guan L X,et al. Mesoprous CaO-ZrO2 Nano-oxides:A Novel Solid Base with High Activity and Stability[J]. Micropor Mesopor Mater,2009,117(1/2):466-471.
[12]	Tian X K,Xiao T,Yang C,et al. Synthesis of Crystalline Ordered Mesoporous CaO-ZrO2 Solid Solution as a Promising Solid Base[J]. Mater Chem Phys,2010,124(1):744-747.
[13]	Xia S F,Guo X M,Mao D S,et al. Biodiesel Synthesis over the CaO-ZrO2 Solid Base Catalyst Prepared by a Urea-Nitrate Combustion Method[J]. RSC Adv,2014,4(93):51688-51695.
[14]	Coleto I,Roldan R,Sanchidrian C J,et al. Valorization of A-olefins:Double Bond Shift and Skeletal Isomerization of 1-Pentene and 1-Hexene on Zirconia-based Catalysts[J]. Catal Today,2010,149(3/4):275-280.
[15]	Xiao Y H,Zheng X H,Chen X H,et al. Synthesis of Mg-doped Ordered Mesoporous Pd-Al2O3 with Different Basicity for CO, NO and HC Elimination[J]. Ind Eng Chem Res,2017,56(7):1687-1695.
[16]	Yuan Q,Li L L,Lu S L,et al. Facile Synthesis of Zr-based Functional Materials with Highly Ordered Mesoporous Structures[J]. J Phys Chem C,2009,113:4117-4124.
[17]	HUANG Hui.Study on Preparation, Modification and Photocatalytic Performance of High-ordered Mesoporous Metal Oxides[D]. Suzhou:Suzhou University,2014(in Chinese). 黄徽. 有序介孔金属氧化物的制备、改性及其光催化性能研究[D]. 苏州,苏州大学,2014.
[18]	Duan H L,Yamada Y,Sato S.Selective Dehydration of 2,3-Butanediol to 3-Buten-2-ol over ZrO2 Modified with CaO[J]. Appl Catal A-Gen,2014,487(10),226-233.
[18]	Wang H,Wang M,Liu S G,et al. Influence of Preparation Methods on the Structure and Performance of CaO-ZrO2 Catalyst for the Synthesis of Dimethyl Carbonate via Transesterification[J]. J Mol Catal A-Chem,2006,258(1/2),308-312.
[19]	Seetharamulu P,Reddy K H P,Padmasri A H,et al.Role of Promoters on Highly Active Nano-Ru, Catalyst Supported on Mg-Al Hydrotalcite Precursor for the Synthesis of Ammonia[J]. Appl Catal,2009,141(1/2),94-98.
[20]	Narasimharao K,Seetharamulu P,Rao K S R,et al.Carbon Covered Mg-Al Hydrotalcite Supported Nanosized Ru Catalysts for Ammonia Synthesis[J]. J Mol Catal A-Chem,2016,411:157-166.