木质素催化氧化解聚研究进展
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摘要
木质素是自然界中唯一能直接提供芳环的可再生资源。然而,受制于其分子中致密的三维网状芳环结构和复杂化学键合方式,超过98%的工业木质素在纸浆和造纸工业中被焚烧,造成极大的资源浪费。木质素氧化解聚转化为香草醛等高度官能化的单体是一个重要且有前景的手段。文章主要介绍了木质素的结构、种类和解聚方法,从催化剂以及催化转化路线方面详细介绍了目前国内外在木质素氧化解聚研究领域的最新进展。在此基础上,对近期热门的非常规活化方法进行了调研与分析。最后总结了当前木质素氧化解聚研究存在的问题,并提出了未来可能的发展方向。
Lignin is the only renewable resource in nature that can directly provide aromatic rings. However,the three-dimensional structure and high stability of lignin bonds make lignin depolymerization highly challenging. As a result, over 98% lignin is burned in the pulp and paper industry, which is a great waste. It is very important and promising for oxidative depolymerization of lignin into platform aromatic compounds with additional functionalities such as vanillin. This paper provides an introduction of lignin structure, type and the depolymerization methods. Meanwhile, advances in lignin oxidative depolymerization based on catalysts and oxidative pathway are reviewed. In addition, various unconventional activation methods are discussed. Finally,possible directions of future development are presented based on problems of oxidative valorization of lignin.
Lignin is the only renewable resource in nature that can directly provide aromatic rings. However,the three-dimensional structure and high stability of lignin bonds make lignin depolymerization highly challenging. As a result, over 98% lignin is burned in the pulp and paper industry, which is a great waste. It is very important and promising for oxidative depolymerization of lignin into platform aromatic compounds with additional functionalities such as vanillin. This paper provides an introduction of lignin structure, type and the depolymerization methods. Meanwhile, advances in lignin oxidative depolymerization based on catalysts and oxidative pathway are reviewed. In addition, various unconventional activation methods are discussed. Finally,possible directions of future development are presented based on problems of oxidative valorization of lignin.
引文
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[8]VANGEEL T,SCHUTYSER W,RENDERS T,et al.Perspective on lignin oxidation:advances,challenges,and future directions[J].Topics in Current Chemistry,2018,376(4):30.
[9]UPTON B M,KASKO A M.Strategies for the conversion of lignin to high-value polymeric materials:Review and perspective[J].Chemical Reviews,2015,116(4):2275-2306.
[10]RINALDI R,JASTRZEBSKI R,CLOUGH M T,et al.Paving the way for lignin valorisation:Recent advances in bioengineering,biorefining and catalysis[J].Angewandte Chemie International Edition,2016,55(29):8164-8215.
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[12]TOLEDANO A,SERRANO L,LABIDI J.Organosolv lignin depolymerization with different base catalysts[J].Journal of Chemical Technology&Biotechnology,2012,87(11):1593-1599.
[13]JIANG X X,Ellis N,ZHONG Z P.Characterization of pyrolytic lignin extracted from bio-oil[J].Chinese Journal of Chemical Engineering,2010,18(6):1018-1022.
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[15]BEHLING R,VALANGE S,CHATEL G.Heterogeneous catalytic oxidation for lignin valorization into valuable chemicals:What results?What limitations?What trends?[J].Green Chemistry,2016,18(7):1839-1854.
[16]BRUIJININCX P C A,WECHUYSEN B M.Biomass conversion:lignin up for break-down[J].Nature Chemistry,2014,6(12):1035.
[17]舒日洋,徐莹,张琦,等,木质素催化解聚的研究进展[J].化工学报,2016,67(11):4524-4532.SHU R Y,XU Y,ZHANG Q,et al.Progress in catalytic depolymerization of lignin[J].CIESC Journal,2016,67(11):4524-4532.
[18]CHAN M K,YE Q,PENG Z M,et al.Valorization of lignin:effective conversion of depolymerized lignin to oil by simple chemical modifications[J].Waste and Biomass Valorization,2017,8(6):2029-2036.
[19]PANDEY M P,KIM C S.Lignin depolymerization and conversion:A review of thermochemical methods[J].Chemical Engineering&Technology,2011,34(1):29-41.
[20]LASKAR D D,TUCKER M P,CHEN X,et al.Noble-metal catalyzed hydrodeoxygenation of biomass-derived lignin to aromatic hydrocarbons[J].Green Chemistry,2014,16(2):897-910.
[21]ZHAI Y X,LI C,Xu G Y,et al.Depolymerization of lignin via a non-precious Ni-Fe alloy catalyst supported on activated carbon[J].Green Chemistry,2017,19(8):1895-1903.
[22]SCHUTYSER W,KRUGER J S,ROBINSON A M,et al.Revisiting alkaline aerobic lignin oxidation[J].Green Chemistry,201820(16):3828-3844.
[23]DAS L,KOLAR P,et al.Heterogeneous catalytic oxidation of lignin into value-added chemicals[J].Biofuels,2012,3(2):155-166.
[24]MA R S,GUO M,ZHANG X.Recent advances in oxidative valorization of lignin[J].Catalysis Today,2018,302:50-60.
[25]RAHIMI A,ULBRICH A,COON J J,et al.Formic-acid-induced depolymerization of oxidized lignin to aromatics[J].Nature,2014,515(7526):249-252.
[26]沈晓骏,黄攀丽,文甲龙,等.木质素氧化还原解聚研究现状[J].化学进展,2017,29(1):162-178.SHEN X J,HUANG P L,WEN J L,et al.Research status of lignin oxidative and reductive depolymerization[J].Progress in Chemistry,2017,29(1):162-178.
[27]YUAN Z,EDEN M R.Recent advances in optimal design of thermochemical conversion of biomass to chemicals and liquid fuels[J].Current Opinion in Chemical Engineering,2015,10:70-76.
[28]MOTA M I F,LOUREIRO J M,et al.Recovery of vanillin and syringaldehyde from lignin oxidation:A review of separation and purification processes[J].Separation&Purification Reviews,2016,45(3):227-259.
[29]TARABANKO V E,TARABANKO N.Catalytic oxidation of lignins into the aromatic aldehydes:General process trends and development prospects[J].International Journal of Molecular Sciences,2017,18(11):2421.
[30]PINTO P C R,DA SILVA E A B,RODRIGUES A E.Biomass conversion[M].Berlin:Springer,2012.
[31]SCHUTYSER W,RENDERS T,et al.Chemicals from lignin:An interplay of lignocellulose fractionation,depolymerisation,and upgrading[J].Chemical Society Reviews,2018,47(3):852-908.
[32]SCHOENHERR S,EBRAHIMI M,CZERMAK P.Lignin-trends and applications[M].London:IntechOpen,2018.
[33]FACHE M,BOUTEVIN B,CAILLOL S.Vanillin production from lignin and its use as a renewable chemical[J].ACS Sustainable Chemistry&Engineering,2015,4(1):35-46.
[34]SALES F G,MARANHAO L C A,LIMA FILHO N M,et al.Kinetic evaluation and modeling of lignin catalytic wet oxidation to selective production of aromatic aldehydes[J].Industrial&Engineering Chemistry Research,2006,45(20):6627-6631.
[35]BHARGAVA S,JANI H,TARDIO J,et al.Catalytic wet oxidation of ferulic acid(a model lignin compound)using heterogeneous copper catalysts[J].Industrial&Engineering Chemistry Research,2007,46(25):8652-8656.
[36]VILLAR J C,CAPEROS A,et al.Oxidation of hardwood kraft-lignin to phenolic derivatives with oxygen as oxidant[J].Wood Science and Technology,2001,35(3):245-255.
[37]DENG W,ZHANG H,WU X,et al.Oxidative conversion of lignin and lignin model compounds catalyzed by CeO 2-supported Pd nanoparticles[J].Green Chemistry,2015,17(11):5009-5018.
[38]DENG H,LIN L,SUN Y,et al.Perovskite-type oxide LaMnO3:An efficient and recyclable heterogeneous catalyst for the wet aerobic oxidation of lignin to aromatic aldehydes[J].Catalysis Letters,2008,126(1/2):106-111.
[39]DENG H,LIN L,SUN Y,et al.Activity and stability of perovskite-type oxide LaCoO3 catalyst in lignin catalytic wet oxidation to aromatic aldehydes process[J].Energy&Fuels,2008,23(1):19-24.
[40]SHILPY M,EHSAN M A,ALI T H,et al.Performance of cobalt titanate towards H2O2 based catalytic oxidation of lignin model compound[J].RSC Advances,2015,5(97):79644-79653.
[41]VOITL T,RUDOLF VON ROHR P.Oxidation of lignin using aqueous polyoxometalates in the presence of alcohols[J].ChemSusChem:Chemistry&Sustainability Energy&Materials,2008,1(8/9):763-769.
[42]GAO T T,ZHOU X F,ZHU Z L.Catalytic conversion of kraft lignin using paper-like Co(salen)as an effective catalyst[J].Drewno.Prace Naukowe.Doniesienia.Komunikaty,2015,58(195):79-90.
[43]DEMESA A G,LAARI A,TURENUN I,et al.Alkaline partial wet oxidation of lignin for the production of carboxylic acids[J].Chemical Engineering&Technology,2015,38(12):2270-2278.
[44]TARABANKO V E,HENDOGINA Y V,PETUHOV D V,et al.On the role of retroaldol reaction in the process of lignin oxidation into vanillin.Kinetics of the vanillideneacetone cleavage in alkaline media[J].Reaction Kinetics and Catalysis Letters,2000,69(2):361-368.
[45]CREIGHTON R H J,GIBBS R D,HIBBERT H.Studies on lignin and related compounds.lxxv.alkaline nitrobenzene oxidation of plant materials and application to taxonomic classification1[J].Journal of the American Chemical Society,1944,66(1):32-37.
[46]DEUSS P J,BARTA K.From models to lignin:Transition metal catalysis for selective bond cleavage reactions[J].Coordination Chemistry Reviews,2016,306:510-532.
[47]XIANG Q,Lee Y Y.Production of oxychemicals from precipitated hardwood lignin[C]//Twenty-Second Symposium on Biotechnology for Fuels and Chemicals.Totowa:Humana Press,2001:71-80.
[48]WU G X,HEITZ M,CHORNET E.Improved alkaline oxidation process for the production of aldehydes(vanillin and syringaldehyde)from steam-explosion hardwood lignin[J].Industrial&Engineering Chemistry Research,1994,33(3):718-723.
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