Catalytic hydrogenolysis of diphenyl ether over Ru supported on amorphous silicon-aluminum-TiO2
-
摘要: 采用蒸汽辅助法合成了无定形硅铝(ASA)-TiO2复合载体,并在此基础上制备了双功能催化剂Ru5/ASA-TiO2。利用X-射线衍射(XRD)、吡啶吸附红外(Py-FTIR)、氨-程序升温脱附(NH3-TPD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和X射线光电子能谱(XPS)等手段对所制备催化剂的结构和酸性进行了详细表征。以二苯醚为褐煤模型化合物,在温和条件下考察了催化剂Ru5/ASA-TiO2加氢解聚4–O–5类型醚键的反应活性,二苯醚的转化率高于98%,苯收率为67.1%。弱Brønsted酸和/或Lewis酸而非强Brønsted酸是提高二苯醚的加氢解聚转化率和苯收率的主要因素,并且反应温度能够影响各类型酸的相对含量从而显著影响二苯醚加氢解聚产物的选择性。Abstract: A bifunctional catalyst of Ru5/ASA-TiO2 was prepared by using a novel silicon-aluminum (ASA)-TiO2 amorphous composite, which was synthesized by a steam-assisted method, as the support. X-ray diffraction (XRD), pyridine adsorption infrared (Py-FTIR), ammonia-temperature-programmed desorption (NH3-TPD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and other methods were used to characterize the structure and the acidity of the prepared catalyst. Using diphenyl ether as the lignite-related model compound, the reaction activity of the Ru5/ASA-TiO2 for the catalytic hydrogenolysis of 4–O–5 type ether bonds was investigated under a mild condition. The results show that the weak acid and/or the Lewis acid rather than the strong Brønsted acid mainly contribute to improve the conversion rate and the benzene yield of the catalytic hydrogenolysis of diphenyl ether. The reaction temperature can influence the relative content of various types of acids to significantly affect the selectivity of the hydrogenolysis products of diphenyl ether. The conversion rate of diphenyl ether is greater than 98% while the benzene yield is 67.1%.
-
Key words:
- hydrogenolysis /
- catalyst /
- lignite /
- model compound /
- ether linkage
-
Table 1 Number of BA and LA sites in different supports a
Sample Relative amount /% cacid /(mmol·g−1)b LA1/LA2d BA/LAd LA1 LA2 ASA-TiO2 59.39 40.61 0.42 1.46 0.30 HZSM-5 0 100 0.50 0 1.22 HZSM-5c 0 100 1.58 0 4.89 TiO2 100 0 0.25 − 0 Ru5/ASA-TiO2 69.11 30.89 0.49 2.24 0.26 a Py-FTIR characterization was performed at 150 °C; b NH3-TPD profiles were obtained in the temperature range of 50−550 °C; c commercial molecular sieve; d relative content of Lewis and Brønsted sites were calculated according to the areas of the absorption peaks and their corresponding extinction coefficients Table 2 Validation tests for the production of benzene over Ru5/ASA-TiO2
Reactant Conv. /% Yield /% 97.0 42.8 7.0 4.5 − 3.9 88.3 30.0 7.0 − 4.8 9.7 92.0 52.1 2.8 2.9 0.5 4.1 > 99% 1.8 6.2 1.4 67.4 − Reaction conditions: reactant (0.2 mmol), catalyst (0.02 g), water (5 mL), 250 °C, 0.2 MPa H2+0.6 MPa N2; a reaction was performed at 160 °C -
[1] THIELEMANN T, SCHMIDT S, GERLING J P. Lignite and hard coal: Energy suppliers for world needs until the year 2100 – an outlook[J]. Int J Coal Geol,2007,72(1):1−14. doi: 10.1016/j.coal.2007.04.003 [2] NOLAN P, SHIPMAN A, RUI H. Coal liquefaction, Shenhua group, and China’s energy security[J]. Eur Manag J,2004,22(2):150−164. doi: 10.1016/j.emj.2004.01.014 [3] DONG L, YUAN Q, YUAN H. Changes of chemical properties of humic acids from crude and fungal transformed lignite[J]. Fuel,2006,85(17/18):2402−2407. doi: 10.1016/j.fuel.2006.05.027 [4] XIE J X, CAO J P, ZHAO X Y, JIANG W, ZHAO L, ZHAO M, BAI H C. Selective cleavage of the diphenyl ether C–O bond over a Ni catalyst supported on AC with different pore structures and hydrophilicities[J]. Energy Fuels,2021,35(11):9599−9608. doi: 10.1021/acs.energyfuels.1c00809 [5] CAO J P, XIE T, ZHAO X Y, ZHU C, JIANG W, ZHAO M, ZHAO Y P, WEI X Y. Selective cleavage of ether C–O bond in lignin-derived compounds over Ru system under different H-sources[J]. Fuel,2021,284:119027. doi: 10.1016/j.fuel.2020.119027 [6] ZHAO C, LERCHER J A. Upgrading pyrolysis oil over Ni/HZSM-5 by cascade reactions[J]. Angew Chem Int Ed,2012,51(24):5935−5940. doi: 10.1002/anie.201108306 [7] TAN Q, WANG G, NIE L, DINSE A, BUDA C, SHABAKER J, RESASCO D E. Different product distributions and mechanistic aspects of the hydrodeoxygenation of m-cresol over platinum and ruthenium catalysts[J]. ACS Catal,2015,5(11):6271−6283. doi: 10.1021/acscatal.5b00765 [8] LUO Z, WANG Y M, HE M Y, ZHAO C. Precise oxygen scission of lignin derived aryl ethers to quantitatively produce aromatic hydrocarbons in water[J]. Green Chem,2015,18(2):433−441. [9] ZAKI M I, HASAN M A, PASUPULETY L. Surface reactions of acetone on Al2O3, TiO2, ZrO2, and CeO2: IR spectroscopic assessment of impacts of the surface acid-base properties[J]. Langmuir,2001,17(3):768−774. doi: 10.1021/la000976p [10] ZAKI M I, HASAN M A, AL-SAGHEE F A, PASUPULETY L. In situ FTIR spectra of pyridine adsorbed on SiO2-Al2O3, TiO2, ZrO2 and CeO2: General considerations for the identification of acid sites on surfaces of finely divided metal oxides[J]. Colloids Surf A Physicochem Eng Asp,2001,190(3):261−274. doi: 10.1016/S0927-7757(01)00690-2 [11] GRIFFIN M B, FERGUSON G A, RUDDY D A, BIDDY M J, SCHAIDLE J A. Role of the support and reaction conditions on the vapor-phase deoxygenation of m-cresol over Pt/C and Pt/TiO2 catalysts[J]. ACS Catal,2016,6(4):2715−2727. doi: 10.1021/acscatal.5b02868 [12] BOONYASUWAT S, OMOTOSO T, RESASCO D E, CROSSLEY S P. Conversion of guaiacol over supported Ru catalysts[J]. Catal Lett,2013,143(8):783−791. doi: 10.1007/s10562-013-1033-3 [13] KARIM W, SPREAFICO C, KLEIBERT A, GOBRECHT J, VANDEVONDELE J, EKINCI Y, VAN BOKHOVEN J A. Catalyst support effects on hydrogen spillover[J]. Nature,2017,541(7635):68−71. doi: 10.1038/nature20782 [14] ALMEIDA A R, MOULIJN J A, MUL G. Photocatalytic oxidation of cyclohexane over TiO2: Evidence for a Mars-van Krevelen mechanism[J]. J Phys Chem C,2011,115(4):1330−1338. doi: 10.1021/jp107290r [15] VOLCKMAR C E, BRON M, BENTRUP U, MARTIN A, CLAUS P. Influence of the support composition on the hydrogenation of acrolein over Ag/SiO2-Al2O3 catalysts[J]. J Catal,2009,261(1):1−8. doi: 10.1016/j.jcat.2008.10.012 [16] NAITO N, KATADA N, NIWA M. Tungsten oxide monolayer loaded on zirconia: Determination of acidity generated on the monolayer[J]. J Phys Chem B,1999,103(34):7206−7213. doi: 10.1021/jp9906381 [17] LI L, LIU G N, QI S P, LIU X D, GU L Y, LOU Y B, CHEN J X, ZHAO Y X. Highly efficient colloidal MnxCd1−xS nanorod solid solution for photocatalytic hydrogen generation[J]. J Mater Chem A,2018,6(46):23683−23689. doi: 10.1039/C8TA08458K [18] NEIMARK A V, RAVIKOVITCH P I, GRÜN M, SCHÜTH F, UNGER K K. Pore size analysis of MCM-41 type adsorbents by means of nitrogen and argon adsorption[J]. J Colloid Interface Sci,1998,207(1):159−169. doi: 10.1006/jcis.1998.5748 [19] SHAMZHY M, PŘECH J, ZHANG J, RUAUX V, EL-SIBLANI H, MINTOVA S. Quantification of Lewis acid sites in 3D and 2D TS-1 zeolites: FTIR spectroscopic study[J]. Catal Today,2020,345:80−87. doi: 10.1016/j.cattod.2019.10.011 [20] VALDÉS-MARTÍNEZ O U, SUÁREZ-TORIELLO V A, REYES J A, PAWELEC B, FIERRO J. Support effect and metals interactions for NiRu/Al2O3, TiO2 and ZrO2 catalysts in the hydrodeoxygenation of phenol[J]. Catal Today,2017,296:219−227. doi: 10.1016/j.cattod.2017.04.007 [21] KANG Y, WEI X Y, LI J, JIN H, LI T, LU C Y, MA X R, ZONG Z. Green and effective catalytic hydroconversion of an extractable portion from an oil sludge to clean jet and diesel fuels over a mesoporous Y zeolite-supported nickel catalyst[J]. Fuel,2021,287:119396. doi: 10.1016/j.fuel.2020.119396 [22] DENG X, WEI Z, CUI C, LIU Q, WANG C, MA J. Oxygen-deficient anatase TiO2@C nanospindles with pseudocapacitive contribution for enhancing lithium storage[J]. J Mater Chem A,2018,6(9):4013−4022. doi: 10.1039/C7TA11301C [23] HERY, HAERUDIN, STEPHAN, BERTEL, REINHARD, KRAMER. Surface stoichiometry of 'titanium suboxide' Part I volumetric and FTIR study[J]. J Chem Soc, Faraday Trans,1998,94(10):1481−1487. doi: 10.1039/a707714i [24] HUANG Y, YAN L, CHEN M, GUO Q, FU Y. Selective hydrogenolysis of phenols and phenyl ethers to arenes through direct C–O cleavage over ruthenium-tungsten bifunctional catalysts[J]. Green Chem,2015,17(5):3010−3017. doi: 10.1039/C5GC00326A [25] NELSON R C, BAEK B, RUIZ P, GOUNDIE B, BROOKS A, WHEELER M C, AUSTIN R N. Experimental and theoretical insights into the hydrogen-efficient direct hydrodeoxygenation mechanism of phenol over Ru/TiO2[J]. ACS Catal,2015,5(11):6509−6523. doi: 10.1021/acscatal.5b01554