孫恩浩，劉　通，閆義彬，曹媛媛，蔣　巖，趙仲陽

(中國石油天然氣股份有限公司大慶化工研究中心，黑龍江 大慶 163714)

?

綜述與展望

孫恩浩*，劉通，閆義彬，曹媛媛，蔣巖，趙仲陽

(中國石油天然氣股份有限公司大慶化工研究中心，黑龍江 大慶 163714)

摘要：介紹固體超強酸催化劑的發(fā)展、特點、應用及改性研究方向,研究催化劑酸強度低、催化劑易失活和穩(wěn)定性差等問題,并提出解決方案。通過對國內(nèi)外/MxOy型固體超強酸催化劑的研究，分析向載體中引入稀土元素、分子篩、其他金屬、納米材料和交聯(lián)劑對固體超強酸催化劑催化活性、熱穩(wěn)定性、酸性、比表面積和晶型等的影響，綜述采用或硫酸鹽替換作為催化劑活性組分對催化劑的催化活性、酸強度及結(jié)構(gòu)等的影響以及引入過渡金屬(貴金屬)形成的雙官能團對催化劑結(jié)構(gòu)與活性的影響，對制約/MxOy型固體超強酸催化劑研究與工業(yè)化應用的催化劑壽命、穩(wěn)定性、機械強度、合成方法、催化活性及催化劑再生等問題進行探討。

關(guān)鍵詞：催化劑工程；固體超強酸/MxOy型催化劑;改性

CLC number:TQ426.6;O643.36Document code: AArticle ID: 1008-1143(2016)05-0013-06

載體是構(gòu)成催化劑的主要部分，是催化劑的骨架。通過優(yōu)化載體，提高催化劑的比表面積，增加活性中心，可提高催化活性。對載體進行改性以增強催化劑的抗失活能力和機械強度，延長催化劑使用壽命。向催化劑載體中引入新元素也具有催化作用，可進一步提高催化劑活性[8-9]。

1.1稀土元素的引入

1.2分子篩的引入

提高催化劑的酸密度和酸強度可以提高催化劑的催化活性，而增大催化劑的比表面積是普遍采用的改性方法。分子篩是一種介孔型催化劑，由于比表面積大、孔徑可調(diào)、內(nèi)晶表面極化度高、吸附能力強且介孔材料可阻止晶粒長大，形成有利于催化反應的四方晶相結(jié)構(gòu)[12]，成為負載型催化劑的優(yōu)良載體。

Wang J A等[13]制備了Pt/H3PW12O40/Zr-MCM-41催化劑，比表面積(359.3～549.2) m2·g-1，酸性中心數(shù)量(360～481) μmol·g-1，表明催化劑酸性很強，催化劑活性非常高，催化劑在低溫反應時，選擇性接近100%，在最適宜反應溫度(280～300)℃，選擇性約90%。Brito A等[14]分別以絲光沸石和ZSM-5合成了固體超強酸催化劑，研究表明，提高比表面積可以提高催化劑的酸強度，并且有金屬骨架制備的載體可以更好的發(fā)揮協(xié)同作用使B酸受L酸影響而加強，與李三喜等[15]結(jié)論一致。

1.3其他載體金屬元素的引入

1.4納米材料的引入

1.5交聯(lián)劑的引入

交聯(lián)黏土是一種多微孔型材料，可通過金屬氧化物(如Al2O3、ZrO2等)或復合金屬氧化物(如Al2O3-Ga2O3等)進行合成，該合成物質(zhì)具有較大的比表面積，在(500～700)℃穩(wěn)定性很好，由于交聯(lián)黏土本身具有一定量的酸性，且對以酸性中心為活性的反應有加強作用，適用于異構(gòu)化反應和加氫裂解反應。Rachid Issaadi等[24]用蒙脫土(M)、鋯(Zr)和硫酸(S)合成了Zr-MS并負載Pd，制備Pd/Zr-MS催化劑，Zr-M的比表面積為247 m2·g-1，未復合Zr黏土的BET比表面積為95 m2·g-1，表明合成的載體具有更好的比表面積，可以提供更多催化活性吸附位。浸漬硫酸負載酸性組分的過程，使催化劑具有催化活性，但催化劑的孔結(jié)構(gòu)被改變，比表面積減至135 m2·g-1，孔容增大，并得到較好的酸強度。以異丙醇脫水反應為探針，丙烷的最初生成速率為16×105mol·(s·g)-1，然后逐漸降低75%的速率，這是由于催化劑表面積炭覆蓋了活性中心，降低了催化活性，需要對催化劑進行再生。

2活性組分的改性

固體超強酸催化劑的活性組分為酸性中心，通過催化劑中L酸和B酸以協(xié)同的方式表現(xiàn)出來，以異構(gòu)化為例，酸性中心可以催化正構(gòu)烷烴重排異構(gòu)化為異構(gòu)烷烴，酸強度在一定程度上決定了催化劑的催化活性，故采用酸強度高和穩(wěn)定性好的酸性組分對催化劑進行改性，制得高活性催化劑。

3過渡金屬的引入

4結(jié)語與展望

今后的研究方向為：(1) 催化劑機械強度研究，可以減少催化劑的孔道塌陷和孔道堵塞，延長其使用壽命；(2) 催化劑合成方法研究，提高催化劑的制備效率和比表面積，改善催化劑的結(jié)構(gòu)，從綠色化工角度優(yōu)化催化活性；(3) 解決催化劑的再生循環(huán)問題，提高催化劑再生后的催化效率，實現(xiàn)催化劑的重復利用。

參考文獻:

[1]Hino M,Kobayashi S,Arata.Reactions of butane and isobutane catalyzed by zirconium oxide treated with sulfate ion.Solid superacid catalyst[J].Journal of the American Chemical Society,1979,101(21):6439-6441.

[2]Hiromi M,Daishi S,Kazushi A,et al.Influence of calcination temperature on the surface acidity of the solid superacid of sulfated alumina[J].Reaction Kinetics and Catalysis Letters,2004,81(1):183-188.

[3]Dan Fraenkel,Nicholas R Jentzsch,Christopher A Starr,et al.Acid strength of solids probed by catalytic isobutane conversion[J].Journal of Catalysis,2010,274:29-51.

[6]Sameer Vijay,Wolf E E.A highly active and stable platinum-modified sulfated zirconia catalyst 1.Preparation and activity for n-pentane isomerization[J].Applied Catalysis A:General,2004,264:117-124.

[10]Jong Rack Sohn,Dong Cheol Shin.Environmentally friendly solid acid catalyst prepared by modifying TiO2with cerium sulfate for the removal of volatile organic chemicals[J].Applied Catalysis B:Environmental,2008,77:386-394.

[12]張六一,韓彩蕓,杜東泉,等.硫酸化氧化鋯固體超強酸[J].化學進展,2011,23(5):860-873.

Zhang Liuyi,Han Caiyun,Du Dongquan，et al.Sulfated zirconia——A superacid[J].Progress in Chemistry,2011,23(5):860-873.

[13]Wang J A,Zhou X L,Chen L F,et al.Hydroisomerization of n-heptane on the Pt/H3PW12O40/Zr-MCM-41 catalysts[J].Journal of Molecular Catalysis A:Chemical,2009,299:68-76.

[14]Brito A,García F J,Alvarez-Galvn M C,et al.Catalytic behaviour of Pt or Pd metal nanoparticles-zeolite bifunctional catalysts for n-pentane hydroisomerization[J].Catalysis Communications,2007,(8):2081-2086.

[16]孫晶,王鼎聰,趙杉林,等.TiO2復合氧化物的制備及其在加氫脫硫中的應用[J].工業(yè)催化，2005,13(8):6-14.

Sun Jing,Wang Dingcong,Zhao Shanlin,et al.Preparation of mixed oxides containing titania and their application in hydrodesulfurization(HDS)[J].Industrial Catalysis，2005,13(8):6-14.

[17]Ahmed M A.Surface characterization and catalytic activity of sulfated-hafnia promoted zirconia catalysts for n-butane isomerization[J].Fuel Processing Technology,2011,92:1121-1128.

[18]Sun Yinyong,Stéphane Walspurger,Benot Louis,et al.Investigation of factors influencing catalytic activity for n-butane isomerization in the presence of hydrogen on Al-promoted sulfated zirconia[J].Applied Catalysis A:General,2009,292:200-207.

[19]Hillary A Prescott,Martin Wloka,Erhard Kemnitz.Supported sulfated zirconia catalysts and their properties[J].Journal of Molecular Catalysis A:Chemical,2004,223(1/2):67-74.

[20]Hernandez-Pichardo M L,Montoya de la Fuente J A,Angel P Del,et al.High-throughput study of the iron promotional effect over Pt/WOx-ZrO2catalysts on the skeletal isomerization of n-hexane[J].Applied Catalysis A:General,2012,431-432:69-78.

[21]周亞松,范小虎.納米TiO2-SiO2復合氧化物的制備與性質(zhì)[J].高等學?；瘜W學報,2003,24(7):1266-1270.

Zhou Yasong,Fan Xiaohu.Preparation and properties of the nanometer composite oxide TiO2-SiO2[J].Chemical Journal of Chinese Universities,2003,24(7):1266-1270.

[22]王東輝,董同欣,史喜成,等.納米金催化劑的抗水性能和抗硫中毒性能[J].催化學報,2007,28(7):657-661.

Wang Donghui,Dong Tongxin,Shi Xicheng,et al.Resistance of nano-sized gold catalysts to water and sulfur poisoning[J].Chinese Journal of Catalysis,2007,28(7):657-661.

[23]Felora Heshmatpour,Reza Babadi Aghakhanpour.Synthesis and characterization of superfine pure tetragonal nanocrystalline sulfated zirconia powder by a non-alkoxide sol-gel route[J].Advanced Powder Technology,2012,23(1):80-87.

[24]Rachid Issaadi,Francois Garin,Chems-Eddine Chitour.Study of the acid character of some palladium-modified pillared clay catalysts:use of isopropanol decomposition as test reaction[J].Catalysis Today,2006,113(3/4):166-173.

[25]Sohn Jong Rack,Lee Si Hoon.Effect of TiO2-ZrO2composition on catalytic activity of supported NiSO4for ethylene dimerization[J].Applied Catalysis A:General,2007,321(1):27-34.

[29]宋華,董鵬飛,石洋.Pt含量及活化溫度對固體超強酸催化劑異構(gòu)化性能的影響[J].高等學?；瘜W學報,2011,32(2):355-360.

[31]Pérez-Luna M,Cosultchi A,Toledo-Antonio J A,et al.n-Pentane isomerization over Pt-and Ni-Pt-promoted sulfated zirconia catalysts supported on alumina[J].Catalysis Letters,2009,131(1):285-293.

[32]Belandria L,Marín-Astorga N,García E,et al.Catalytic activity of Pt and Pd catalysts supported on HWP/HMS in the selective hydroisomerization of n-pentane.Effect of reaction temperature[J].Catalysis Today,2011,172(1):2-7.

[33]Herma Dina Setiabudi,Aishah Abdul Jalil,Sugeng Triwahyono,et al.IR study of iridium bonded to perturbed silanol groups of Pt-HZSM5 for n-pentane isomerization[J].Applied Catalysis A:General,2012,417-418:190-199.

[34]Sachin Kumar,Vimal Chandra Srivastava,Badoni R P.Oxidative desulfurization by chromium promoted sulfated zirconia[J].Fuel Processing Technology,2012,93(1):18-25.

Sun Enhao*, Liu Tong, Yan Yibin, Cao Yuanyuan, Jiang Yan, Zhao Zhongyang

(Daqing Petrochemical Research Center of PetroChina, Daqing 163714, Heilongjiang, China)

Abstract:The development,characteristics,application and modification of solid superacid catalysts were introduced.The existing problems of low acid strength,easy deactivation and poor stability of the catalysts,etc. were investigated,and the solutions were put forward.Through the research of domestic and international /MxOy solid superacid catalysts,the effects of rare earth element introduction,molecular sieves,other carrier metals,nano materials,and crosslinking agents on catalytic activity,thermal stability,acidity,surface area and crystal type of solid superacid catalysts were analyzed.Substituting or sulfate for ,the influence of or sulfate as the activity components of the catalysts on catalytic activity,acid strength and structure of the catalysts,and the effects of the introduction of transition metals (precious metals) formed the bifunctional catalysts on structure and catalytic activity of the catalysts were reviewed.The problems such as catalyst life,stability,mechanical strength,synthesis methods,catalytic activity and catalyst regeneration,which restricted the research on and commercial application of solid superacid catalysts,were discussed.

Key words:catalyst engineering; solid superacid; /MxOy catalyst; modification

收稿日期：2015-11-03；修回日期：2016-03-29

作者簡介：孫恩浩,1989年生,男，黑龍江省大慶市人，碩士，工程師，研究方向為工業(yè)催化。

doi:10.3969/j.issn.1008-1143.2016.05.003 10.3969/j.issn.1008-1143.2016.05.003

中圖分類號：TQ426.6;O643.36

文獻標識碼：A

文章編號：1008-1143(2016)05-0013-06

通訊聯(lián)系人：孫恩浩。