碳球表面缺陷密度对其负载铜催化剂甲醇氧化羰基化反应性能的影响
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摘要
采用水热聚合法合成了一系列表面缺陷密度不同的有序微孔碳球(CS),并以其为载体制备了表面负载铜催化剂(Cu/CS),用于催化气相甲醇氧化羰基化合成碳酸二甲酯。结合表征结果,研究了载体表面缺陷密度对Cu/CS催化剂结构及催化性能的影响。结果表明,CS的表面缺陷密度随其粒径增大而增大,且其缺陷密度越大,催化剂中Cu物种分散度越高;同时,较大的表面缺陷密度有利于增强载体与Cu物种间的相互作用力,促进CuO自还原为活性物种Cu2O和Cu,从而提高催化活性。长期评价结果表明,Cu物种的氧化和团聚是造成Cu/CS催化剂失活的原因。CS的表面缺陷抑制了反应过程中活性Cu物种的氧化,且缺陷密度越大,Cu物种抗氧化能力越强;但表面缺陷密度大的催化剂中Cu物种颗粒尺寸小,表面能高,因而更容易发生团聚。
A series of ordered microporous carbon spheres(CS) with different surface defect density were prepared by hydrothermal polymerization method, then the CS surface-supported Cu catalysts were prepared and evaluated for methanol oxidative carbonylation to synthesize dimethyl carbonate. From the characterization results, the influence of surface defect density of CS on the structure and the catalytic performance of Cu/CS were studied. The results indicated that the surface defect density of CS increase with the increase of its particle size, and the dispersion of Cu species became better with the increase of surface defect density. Moreover, the increased surface defect density was conducive to the enhanced interaction between CS and Cu species, and to the auto-reduction of CuO to active species Cu2 O and Cu,and thus improved the catalytic activity. The long-term evaluation results suggested that the oxidation and agglomeration of Cu species resulted in the deactivation of Cu/CS catalysts. The surface defect of CS inhibited the oxidation of active Cu species in the reaction process. The higher surface defect density, the stronger the antioxidant capacity of Cu species. However, the Cu species with small particle size induced by high surface defect density aggregated easily in the reaction process due to their high surface energy.
A series of ordered microporous carbon spheres(CS) with different surface defect density were prepared by hydrothermal polymerization method, then the CS surface-supported Cu catalysts were prepared and evaluated for methanol oxidative carbonylation to synthesize dimethyl carbonate. From the characterization results, the influence of surface defect density of CS on the structure and the catalytic performance of Cu/CS were studied. The results indicated that the surface defect density of CS increase with the increase of its particle size, and the dispersion of Cu species became better with the increase of surface defect density. Moreover, the increased surface defect density was conducive to the enhanced interaction between CS and Cu species, and to the auto-reduction of CuO to active species Cu2 O and Cu,and thus improved the catalytic activity. The long-term evaluation results suggested that the oxidation and agglomeration of Cu species resulted in the deactivation of Cu/CS catalysts. The surface defect of CS inhibited the oxidation of active Cu species in the reaction process. The higher surface defect density, the stronger the antioxidant capacity of Cu species. However, the Cu species with small particle size induced by high surface defect density aggregated easily in the reaction process due to their high surface energy.
引文
[1] FU Z H, ONO Y. Two-step synthesis of diphenyl carbonate from dimethyl carbonate and phenol using MoO3/SiO2catalysts[J]. Journal of Molecular Catalysis A Chemical, 1997, 118(3):293-299.
[2] ONO Y. Catalysis in the production and reactions of dimethyl carbonate, an environmentally benign building block[J]. Applied Catalysis A:General, 1997, 155(2):133-166.
[3] WANG Y J, ZHAO X Q, YUAN B G, et al. Synthesis of dimethyl carbonate by gas-phase oxidative carbonylation of methanol on the supported solid catalystⅠ. Catalyst preparation and catalytic properties[J]. Applied Catalysis A:General, 1998, 171(2):255-260.
[4] FIORANI G, PEROSA A, SELVA M. Dimethyl carbonate:a versatile reagent for a sustainable valorization of renewables[J]. Green Chemistry, 2017, 20(2):288-322.
[5] TUNDO P, SELVA M. The chemistry of dimethyl carbonate[J]. ACC Chem. Res., 2002, 35(9):706-716.
[6]宋一兵,罗爱国,杜玉海,等.甲醇直接气相氧化羰基化合成碳酸二甲酯[J].化学进展, 2008, 20(2):221-226.SONG Y B, LUO A G, DU Y H, et al. Synthesis of dimethyl carbonate by direct vapor-phase oxycarbonylation of methanol[J]. Progress of Chemistry, 2008, 20(2):221-226.
[7] WANG R Y, LI Z, ZHENG H Y. Preparation of chlorine-free Cu/AC catalyst and its catalytic properties for vapor phase oxidative carbonylation of methanol[J]. Chinese Journal of Catalysis, 2010, 31(7):851-856.
[8] LI Z, WEN C M, WANG R Y, et al. Chloride-free Cu2O/AC catalyst prepared by pyrolysis of copper acetate and catalytic oxycarbonylation[J]. Chemical Journal of Chinese Universities, 2009, 30(10):2024-2031.
[9] REN J, WANG W, WANG D L, et al. A theoretical investigation on the mechanism of dimethyl carbonate formation on Cu/AC catalyst[J].Applied Catalysis A:General, 2014, 472(472):47-52.
[10] ZHANG R G, SONG L Z, WANG B J, et al. A density functional theory investigation on the mechanism and kinetics of dimethyl carbonate formation on Cu2O catalyst.[J]. Journal of Computational Chemistry,2012, 33(11):1101-1110.
[11] FU T J, WANG X, ZHENG H Y, et al. Effect of Cu location and dispersion on carbon sphere supported Cu catalysts for oxidative carbonylation of methanol to dimethyl carbonate[J]. Carbon, 2017, 115:363-374.
[12] ZHANG G Q, YAN J F, WANG J J, et al. Effect of carbon support on the catalytic performance of Cu-based nanoparticles for oxidative carbonylation of methanol[J]. Applied Surface Science, 2018, 455:696-704.
[13] DESHMUKH A A, MHLANGA S D, COVILLE N J. Carbon spheres[J].Materials Science&Engineering R, 2010, 70(1/2):1-28.
[14] MORENO C C. Colloidal and micro-carbon spheres derived from lowtemperature polymerization reactions[J]. Advances in Colloid&Interface Science, 2016, 236:113-141.
[15] WANG J, HAO P P, SHI R N, et al. Fabrication of yolk-shell Cu@C nanocomposites as high-performance catalysts in oxidative carbonylation of methanol to dimethyl carbonate[J]. Nanoscale Research Letters, 2017, 12(1):481.
[16] HAO P P, REN J, YANG L L, et al. Direct and generalized synthesis of carbon-based yolk-shell nanocomposites from metal-oleate precursor[J]. Chemical Engineering Journal, 2016, 283:113-141.
[17] LI H X, ZHAO J X, SHI R N, et al. Remarkable activity of nitrogendoped hollow carbon spheres encapsulated Cu on synthesis of dimethyl carbonate:role of effective nitrogen[J]. Applied Surface Science, 2018,436:803-813.
[18] FANG Y, GU D, ZOU Y, et al. A low-concentration hydrothermal synthesis of biocompatible ordered mesoporous carbon nanospheres with tunable and uniform size[J]. Angewandte Chemie, 2010, 49(43):7987-7991.
[19] SING K S W, WILLIAMS R T. Physisorption hysteresis loops and the characterization of nanoporous materials[J]. Adsorption Science&Technology, 2004, 22(10):773-782.
[20] SONG S, JIANG S. Selective catalytic oxidation of ammonia to nitrogen over CuO/CNTs:the promoting effect of the defects of CNTs on the catalytic activity and selectivity[J]. Applied Catalysis B:Environmental, 2012, 117/118(1):346-350.
[21] SUZUKI S, HIBINO H. Characterization of doped single-wall carbon nanotubes by Raman spectroscopy[J]. Carbon, 2011, 49(7):2264-2272.
[22] LIN C R, SU C H, CHANG C Y, et al. Synthesis of nanosized flake carbons by RF-chemical vapor method[J]. Surface&Coatings Technology, 2006, 200(10):3190-3193.
[23] SONG S, YANG H, RAO R, et al. Defects of multi-walled carbon nanotubes as active sites for benzene hydroxylation to phenol in the presence of HO[J]. Catalysis Communications, 2010, 11(8):783-787.
[24] RODRíGUEZMANZO J A, CRETU O, BANHART F. Trapping of metal atoms in vacancies of carbon nanotubes and graphene[J]. ACS Nano, 2010, 4(6):3422-3428.
[25] SONG S, JIANG S, RAO R, et al. Bicomponent VO2-defects/MWCNT catalyst for hydroxylation of benzene to phenol:promoter effect of defects on catalytic performance[J]. Applied Catalysis A:General,2011, 401(1):215-219.
[26] GROBMANN D, DREIER A, LEHMANN C W, et al. Encapsulation of copper and zinc oxide nanoparticles inside small diameter carbon nanotubes[J]. Microporous&Mesoporous Materials, 2015, 202(4):189-197.
[27] YAN B, HUANG S S, WANG S P, et al. Catalytic oxidative carbonylation over Cu2O nanoclusters supported on carbon materials:the role of the carbon support[J]. Chemcatchem, 2014, 6(9):2671-2679.
[28] SONG S Q, RAO R C, YANG H X, et al. Cu2O/MWCNTs prepared by spontaneous redox:growth mechanism and superior catalytic activity[J]. Journal of Physical Chemistry C, 2010, 114(33):13998-14003.
[29] ZHANG Z L, CHE H W, WANG Y L, et al. Template-free synthesis of Cu@Cu2O core-shell microspheres and their application as copperbased catalysts for dimethyldichlorosilane synthesis[J]. Chemical Engineering Journal, 2012, 211(47):421-431.
[30] ZHANG G Q, LI Z, ZHENG H Y, et al. Influence of the surface oxygenated groups of activated carbon on preparation of a nano Cu/AC catalyst and heterogeneous catalysis in the oxidative carbonylation of methanol[J]. Applied Catalysis B:Environmental, 2015, 179:95-105.
[31] HU Q, FAN G L, ZHANG S Y, et al. Gas phase hydrogenation of dimethyl-1, 4-cyclohexane dicarboxylate over highly dispersed and stable supported copper-based catalysts[J]. Journal of Molecular Catalysis A:Chemical, 2015, 397:134-141.
[32] CHAKRABORTY A K, WOOLLEY R A J, BUTENKO Y V, et al. A photoelectron spectroscopy study of ion-irradiation induced defects in single-wall carbon nanotubes[J]. Carbon, 2007, 45(14):2744-2750.
[33] ESPINóS J P, MORALES J, BARRANCO A, et al. Interface effects for Cu, CuO, and Cu2O deposited on SiO2and ZrO2. XPS determination of the valence state of copper in Cu/SiO2and Cu/ZrO2catalysts[J].Journal of Physical Chemistry B, 2002, 106(27):6921-6929.
[34] ZHANG G Q, LI Z, ZHENG H Y, et al. Influence of surface oxygenated groups on the formation of active Cu species and the catalytic activity of Cu/AC catalyst for the synthesis of dimethyl carbonate[J]. Applied Surface Science, 2016, 390:68-77.
[35] HANSEN T W, DELARIVA A T, CHALLA S R, et al. Sintering of catalytic nanoparticles:particle migration or Ostwald ripening[J].Accounts of Chemical Research, 2013, 46(8):1720-1730.
[36] YE R P, LIN L, LI Q H, et al. Recent progress in improving the stability of copper-based catalysts for hydrogenation of carbon-oxygen bonds[J]. Catalysis Science&Technology, 2018, 8(14):3428-3449.
[2] ONO Y. Catalysis in the production and reactions of dimethyl carbonate, an environmentally benign building block[J]. Applied Catalysis A:General, 1997, 155(2):133-166.
[3] WANG Y J, ZHAO X Q, YUAN B G, et al. Synthesis of dimethyl carbonate by gas-phase oxidative carbonylation of methanol on the supported solid catalystⅠ. Catalyst preparation and catalytic properties[J]. Applied Catalysis A:General, 1998, 171(2):255-260.
[4] FIORANI G, PEROSA A, SELVA M. Dimethyl carbonate:a versatile reagent for a sustainable valorization of renewables[J]. Green Chemistry, 2017, 20(2):288-322.
[5] TUNDO P, SELVA M. The chemistry of dimethyl carbonate[J]. ACC Chem. Res., 2002, 35(9):706-716.
[6]宋一兵,罗爱国,杜玉海,等.甲醇直接气相氧化羰基化合成碳酸二甲酯[J].化学进展, 2008, 20(2):221-226.SONG Y B, LUO A G, DU Y H, et al. Synthesis of dimethyl carbonate by direct vapor-phase oxycarbonylation of methanol[J]. Progress of Chemistry, 2008, 20(2):221-226.
[7] WANG R Y, LI Z, ZHENG H Y. Preparation of chlorine-free Cu/AC catalyst and its catalytic properties for vapor phase oxidative carbonylation of methanol[J]. Chinese Journal of Catalysis, 2010, 31(7):851-856.
[8] LI Z, WEN C M, WANG R Y, et al. Chloride-free Cu2O/AC catalyst prepared by pyrolysis of copper acetate and catalytic oxycarbonylation[J]. Chemical Journal of Chinese Universities, 2009, 30(10):2024-2031.
[9] REN J, WANG W, WANG D L, et al. A theoretical investigation on the mechanism of dimethyl carbonate formation on Cu/AC catalyst[J].Applied Catalysis A:General, 2014, 472(472):47-52.
[10] ZHANG R G, SONG L Z, WANG B J, et al. A density functional theory investigation on the mechanism and kinetics of dimethyl carbonate formation on Cu2O catalyst.[J]. Journal of Computational Chemistry,2012, 33(11):1101-1110.
[11] FU T J, WANG X, ZHENG H Y, et al. Effect of Cu location and dispersion on carbon sphere supported Cu catalysts for oxidative carbonylation of methanol to dimethyl carbonate[J]. Carbon, 2017, 115:363-374.
[12] ZHANG G Q, YAN J F, WANG J J, et al. Effect of carbon support on the catalytic performance of Cu-based nanoparticles for oxidative carbonylation of methanol[J]. Applied Surface Science, 2018, 455:696-704.
[13] DESHMUKH A A, MHLANGA S D, COVILLE N J. Carbon spheres[J].Materials Science&Engineering R, 2010, 70(1/2):1-28.
[14] MORENO C C. Colloidal and micro-carbon spheres derived from lowtemperature polymerization reactions[J]. Advances in Colloid&Interface Science, 2016, 236:113-141.
[15] WANG J, HAO P P, SHI R N, et al. Fabrication of yolk-shell Cu@C nanocomposites as high-performance catalysts in oxidative carbonylation of methanol to dimethyl carbonate[J]. Nanoscale Research Letters, 2017, 12(1):481.
[16] HAO P P, REN J, YANG L L, et al. Direct and generalized synthesis of carbon-based yolk-shell nanocomposites from metal-oleate precursor[J]. Chemical Engineering Journal, 2016, 283:113-141.
[17] LI H X, ZHAO J X, SHI R N, et al. Remarkable activity of nitrogendoped hollow carbon spheres encapsulated Cu on synthesis of dimethyl carbonate:role of effective nitrogen[J]. Applied Surface Science, 2018,436:803-813.
[18] FANG Y, GU D, ZOU Y, et al. A low-concentration hydrothermal synthesis of biocompatible ordered mesoporous carbon nanospheres with tunable and uniform size[J]. Angewandte Chemie, 2010, 49(43):7987-7991.
[19] SING K S W, WILLIAMS R T. Physisorption hysteresis loops and the characterization of nanoporous materials[J]. Adsorption Science&Technology, 2004, 22(10):773-782.
[20] SONG S, JIANG S. Selective catalytic oxidation of ammonia to nitrogen over CuO/CNTs:the promoting effect of the defects of CNTs on the catalytic activity and selectivity[J]. Applied Catalysis B:Environmental, 2012, 117/118(1):346-350.
[21] SUZUKI S, HIBINO H. Characterization of doped single-wall carbon nanotubes by Raman spectroscopy[J]. Carbon, 2011, 49(7):2264-2272.
[22] LIN C R, SU C H, CHANG C Y, et al. Synthesis of nanosized flake carbons by RF-chemical vapor method[J]. Surface&Coatings Technology, 2006, 200(10):3190-3193.
[23] SONG S, YANG H, RAO R, et al. Defects of multi-walled carbon nanotubes as active sites for benzene hydroxylation to phenol in the presence of HO[J]. Catalysis Communications, 2010, 11(8):783-787.
[24] RODRíGUEZMANZO J A, CRETU O, BANHART F. Trapping of metal atoms in vacancies of carbon nanotubes and graphene[J]. ACS Nano, 2010, 4(6):3422-3428.
[25] SONG S, JIANG S, RAO R, et al. Bicomponent VO2-defects/MWCNT catalyst for hydroxylation of benzene to phenol:promoter effect of defects on catalytic performance[J]. Applied Catalysis A:General,2011, 401(1):215-219.
[26] GROBMANN D, DREIER A, LEHMANN C W, et al. Encapsulation of copper and zinc oxide nanoparticles inside small diameter carbon nanotubes[J]. Microporous&Mesoporous Materials, 2015, 202(4):189-197.
[27] YAN B, HUANG S S, WANG S P, et al. Catalytic oxidative carbonylation over Cu2O nanoclusters supported on carbon materials:the role of the carbon support[J]. Chemcatchem, 2014, 6(9):2671-2679.
[28] SONG S Q, RAO R C, YANG H X, et al. Cu2O/MWCNTs prepared by spontaneous redox:growth mechanism and superior catalytic activity[J]. Journal of Physical Chemistry C, 2010, 114(33):13998-14003.
[29] ZHANG Z L, CHE H W, WANG Y L, et al. Template-free synthesis of Cu@Cu2O core-shell microspheres and their application as copperbased catalysts for dimethyldichlorosilane synthesis[J]. Chemical Engineering Journal, 2012, 211(47):421-431.
[30] ZHANG G Q, LI Z, ZHENG H Y, et al. Influence of the surface oxygenated groups of activated carbon on preparation of a nano Cu/AC catalyst and heterogeneous catalysis in the oxidative carbonylation of methanol[J]. Applied Catalysis B:Environmental, 2015, 179:95-105.
[31] HU Q, FAN G L, ZHANG S Y, et al. Gas phase hydrogenation of dimethyl-1, 4-cyclohexane dicarboxylate over highly dispersed and stable supported copper-based catalysts[J]. Journal of Molecular Catalysis A:Chemical, 2015, 397:134-141.
[32] CHAKRABORTY A K, WOOLLEY R A J, BUTENKO Y V, et al. A photoelectron spectroscopy study of ion-irradiation induced defects in single-wall carbon nanotubes[J]. Carbon, 2007, 45(14):2744-2750.
[33] ESPINóS J P, MORALES J, BARRANCO A, et al. Interface effects for Cu, CuO, and Cu2O deposited on SiO2and ZrO2. XPS determination of the valence state of copper in Cu/SiO2and Cu/ZrO2catalysts[J].Journal of Physical Chemistry B, 2002, 106(27):6921-6929.
[34] ZHANG G Q, LI Z, ZHENG H Y, et al. Influence of surface oxygenated groups on the formation of active Cu species and the catalytic activity of Cu/AC catalyst for the synthesis of dimethyl carbonate[J]. Applied Surface Science, 2016, 390:68-77.
[35] HANSEN T W, DELARIVA A T, CHALLA S R, et al. Sintering of catalytic nanoparticles:particle migration or Ostwald ripening[J].Accounts of Chemical Research, 2013, 46(8):1720-1730.
[36] YE R P, LIN L, LI Q H, et al. Recent progress in improving the stability of copper-based catalysts for hydrogenation of carbon-oxygen bonds[J]. Catalysis Science&Technology, 2018, 8(14):3428-3449.