Developing biomass platform compounds into high value-added chemicals is a key step in renewable resource utilization.Herein,we report porous carbon-supported Ni-ZnO nanoparticles catalyst(Ni-ZnO/AC)synthesized via lo...Developing biomass platform compounds into high value-added chemicals is a key step in renewable resource utilization.Herein,we report porous carbon-supported Ni-ZnO nanoparticles catalyst(Ni-ZnO/AC)synthesized via low-temperature coprecipitation,exhibiting excellent performance for the selective hydrogenation of 5-hydroxymethylfurfural(HMF).A linear correlation is first observed between solvent polarity(E_(T)(30))and product selectivity within both polar aprotic and protic solvent classes,suggesting that solvent properties play a vital role in directing reaction pathways.Among these,1,4-dioxane(aprotic)favors the formation of 2,5-bis(hydroxymethyl)furan(BHMF)with 97.5%selectivity,while isopropanol(iPrOH,protic)promotes 2,5-dimethylfuran production with up to 99.5%selectivity.Mechanistic investigations further reveal that beyond polarity,proton-donating ability is critical in facilitating hydrodeoxygenation.iPrOH enables a hydrogen shuttle mechanism where protons assist in hydroxyl group removal,lowering the activation barrier.In contrast,1,4-dioxane,lacking hydrogen bond donors,stabilizes BHMF and hinders further conversion.Density functional theory calculations confirm a lower activation energy in iPrOH(0.60 eV)compared to 1,4-dioxane(1.07 eV).This work offers mechanistic insights and a practical strategy for solvent-mediated control of product selectivity in biomass hydrogenation,highlighting the decisive role of solvent-catalyst-substrate interactions.展开更多
The selective hydrogenation ofα,β-unsaturated aldehydes/ketones enables precise control over product structures and properties by regulating hydrogen transport pathways and bond cleavage sequences to selectively red...The selective hydrogenation ofα,β-unsaturated aldehydes/ketones enables precise control over product structures and properties by regulating hydrogen transport pathways and bond cleavage sequences to selectively reduce C=C or C=O bonds while preserving other functional groups within the molecule.This approach serves as a critical strategy for the directional synthesis of high-value molecules.However,achieving such selectivity remains challenging due to the thermodynamic equilibrium and kinetic competition between C=O and C=C bonds inα,β-unsaturated systems.Consequently,constructing precisely targeted catalytic systems is essential to overcome these limitations,offering both fundamental scientific significance and industrial application potential.Metal-organic frameworks(MOFs)and their derivatives have emerged as innovative platforms for designing such systems,owing to their programmable topology,tunable pore microenvironments,spatially controllable active sites,and modifiable electronic structures.This review systematically summarizes the research progress of MOF-based catalysts for selec-tive hydrogenation ofα,β-unsaturated aldehydes/ketones in the last decade,with emphasis on the design strategy,conformational relationship,and catalytic mechanism,aiming to provide new ideas for the design of targeted catalyt-ic systems for the selective hydrogenation ofα,β-unsaturated aldehydes/ketones.展开更多
The aqueous-phase hydrogenation of furfural to furfuryl alcohol using non-noble metal catalysts is constrained by the low activity of catalysts,necessitating high temperatures and high hydrogen pressures,and posing ch...The aqueous-phase hydrogenation of furfural to furfuryl alcohol using non-noble metal catalysts is constrained by the low activity of catalysts,necessitating high temperatures and high hydrogen pressures,and posing challenges in controlling furfuryl alcohol selectivity.Herein,a Co nanoparticle catalyst supported on nitrogendoped carbon derived from MOFs is reported,which adopts a synergistic strategy to enhance catalytic perfor-mance.The nitrogen doping simultaneously promotes hydrogen spillover on the catalyst surface and reduces surface acidity,thereby suppressing acid-catalyzed side reactions.This dual function enables the selective hy-drogenation of-C=O groups to-CH_(2)OH groups in water under mild conditions.Furfural reached 98%con-version with 95%selectivity of furfuryl alcohol at 135℃ and under hydrogen pressure close to atmospheric(0.4 MPa)in 2 h.This study allows a low energy-consuming method for producing furfuryl alcohol from hemicellulose-derived furfural,and provides a promising strategy for the conversion of renewable biomassderived compounds into high value-added chemicals.展开更多
Hierarchical Ni/ZSM-22-SBA-15 meso-microporous catalysts(Ni/ZS-x)with different acid properties and diffusion characteristics(acid-diffusion)properties were synthesized successfully and applied to the production of hi...Hierarchical Ni/ZSM-22-SBA-15 meso-microporous catalysts(Ni/ZS-x)with different acid properties and diffusion characteristics(acid-diffusion)properties were synthesized successfully and applied to the production of high-quality jet fuel by the efficient one-step hydrogenation(hydrodeoxygenation,isomerization,and cracking)of oleic acid.The acid-diffusion properties of the catalysts are modulated by tuning the ZSM-22 seed content,and their effects on the hydrogenation reactions were investigated.Acid properties affect the extent of isomerization and cleavage reactions,whereas diffusion properties affect the accessibility of active centers.The balanced acid-diffusion properties are conducive to efficient hydrogenation reactions of oleic acid.The optimal Ni/ZS-3 exhibits the highest jet fuel yield(56.3%,340°C)and superior iso/n-alkane ratio(i/n=3.12)because of its well-balanced acid-diffusion properties.Besides,the possible hydrogenation mechanism of oleic acid is proposed.展开更多
Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of C=C over C=O.Herein,a novel Al_(2)O_(3)/C-u hybrid catalyst,...Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of C=C over C=O.Herein,a novel Al_(2)O_(3)/C-u hybrid catalyst,composed of N-modified dendritic carbon networks supporting Al_(2)O_(3)nanoparticles,was successfully prepared via carbonizing the freeze-dried gel from spontaneous cross-linking of alginate,Al3+and urea.The obtained carbon-supported Al_(2)O_(3)hybrid catalyst has a high ratio (31%) of Al species in pentahedral-coordinated state.The introduction of urea enhances the surface N content,the ratio of pyrrolic N,and specific surface area of catalyst,leading to improved adsorption capacity of C=O and the accessibility of active sites.In the furfural hydrogenation reaction with isopropyl alcohol as hydrogen donor,Al_(2)O_(3)/C-u catalyst achieved a 90%conversion of furfural with 98.0% selectivity to furfuryl alcohol,outperforming that of commercial γ-Al_(2)O_(3).Moreover,Al_(2)O_(3)/C-u demonstrates excellent catalytic stability in the recycling tests attributed to the synergistic effect of abundant weak Lewis acid sites and the anchoring effect of the carbon network on Al_(2)O_(3)nanoparticles.This work provides an innovative and facile strategy for fabrication of carbon-supported Al_(2)O_(3)hybrid catalysts with rich AlVspecies,serving as a high selective hydrogenation catalyst through MPV reaction route.展开更多
Pd/C catalysts were prepared by deposited Pd nanoparticles (NPs) on different carbon supports including activated carbon (AC), graphite oxide (GO), and reduced graphite oxide (rGO) using sol-immobilization met...Pd/C catalysts were prepared by deposited Pd nanoparticles (NPs) on different carbon supports including activated carbon (AC), graphite oxide (GO), and reduced graphite oxide (rGO) using sol-immobilization method. Through transmission electron microscopy, powder X-ray di raction, and X-ray photoelectron spectroscopy, the role of the carbon supports for the catalytic performances of Pd/C catalysts was examined in selective hydrogenation of acetylene. The results indicate that Pd/AC exhibited higher activity and selectivity than Pd/GO and Pd/rGO in the gas phase selective hydrogenation of acetylene. Thermal and chemical treatment of AC supports also have some effect on the catalytic performance of Pd/AC catalysts. The differences in the activity and selectivity of various Pd/C catalysts were partly attributed to the metal-support interaction.展开更多
A catalyst consisting of platinum nanoparticles on a ZIF-8 support(Pt@ZIF-8) was synthesized in a straightforward one-step procedure,by adding a nanostructured platinum sol during the formation of ZIF-8 at room temp...A catalyst consisting of platinum nanoparticles on a ZIF-8 support(Pt@ZIF-8) was synthesized in a straightforward one-step procedure,by adding a nanostructured platinum sol during the formation of ZIF-8 at room temperature.Pt@ZIF-8 was highly porous and well crystallized.The Pt nanoparticles were well dispersed within the ZIF-8 support.In the hydrogenation of 1,4-butynediol,Pt@ZIF-8 exhibited high activity,excellent selectivity for 1,4-butenediol of greater than 94%,and reusability.The Pt@ZIF-8 catalyst did not require further additives.The favorable catalytic performance was attributed primarily to the modification of the ZIF-8 support by the platinum nanoparticles.展开更多
The IB metal(Au,Ag and Cu)alloyed Pd single atom catalysts had been proved to be efficient in promoting the selectivity for hydrogenation of acetylene to ethylene.As a base metal in the same group as Pd,the Ni-based c...The IB metal(Au,Ag and Cu)alloyed Pd single atom catalysts had been proved to be efficient in promoting the selectivity for hydrogenation of acetylene to ethylene.As a base metal in the same group as Pd,the Ni-based catalysts are also active for hydrogenation reactions.Herein,the effects of the IB metals on the Ni/SiO2 catalyst for the selective hydrogenation of acetylene were systematically studied.Different from the Pd/SiO2 catalyst,the monometallic Ni/SiO2 catalyst is not active at low temperatures.The addition of the IB metals to the Ni/SiO2 catalysts can greatly enhance the activity.Besides,the catalytic activity of the AuNix/SiO2 and CuNix/SiO2 catalysts increase with the reduction temperature,while the AgNix/SiO2 catalysts are not sensitive to the pretreatment temperature.The origin of the effect of the different IB metals on the Ni-based catalysts for selective hydrogenation of acetylene is discussed based on the characterizations by XRD,TPR and microcalorimetric measurements.展开更多
An efficient heterogeneous catalyst,Pd@MIL‐101(Cr)‐NH2,is prepared through a direct pathway of anionic exchange followed by hydrogen reduction with amino‐containing MIL‐101as the host matrix.The composite is therm...An efficient heterogeneous catalyst,Pd@MIL‐101(Cr)‐NH2,is prepared through a direct pathway of anionic exchange followed by hydrogen reduction with amino‐containing MIL‐101as the host matrix.The composite is thermally stable up to350°C and the Pd nanoparticles uniformly disperse on the matal organic framework(MOF)support,which are attributed to the presence of the amino groups in the frameworks of MIL‐101(Cr)‐NH2.The selective hydrogenation of biomass‐based furfural to tetrahydrofurfuryl alcohol is investigated by using this multifunctional catalyst Pd@MIL‐101(Cr)‐NH2in water media.A complete hydrogenation of furfural is achieved at a low temperature of40°C with the selectivity of tetrahydrofurfuryl alcohol close to100%.The amine‐functionalized MOF improves the hydrogen bonding interactions between the intermediate furfuryl alcohol and the support,which is conducive for the further hydrogenation of furfuryl alcohol to tetrahydrofurfuryl alcohol in good coordination with the metal sites.展开更多
The effect of La on the performance of a supported RuB amorphous alloy catalyst for benzene selective hydrogenation was studied by means of activity and selectivity tests, such as HRTEM, SAED, XPS, and XRD. The result...The effect of La on the performance of a supported RuB amorphous alloy catalyst for benzene selective hydrogenation was studied by means of activity and selectivity tests, such as HRTEM, SAED, XPS, and XRD. The results show that the addition of La to RuB amorphous alloy catalyst can evidently increase the activity and improve the thermal stability of RuB amorphous alloy to refrain its crystallization. The promoting effect of La on the activity of RuB amorphous alloy catalyst is because of the high dispersion of the active components.展开更多
A novel nanosized amorphous Ru-Fe-B/ZrO2 alloy catalyst for benzene selective hydrogenation to cyclohexene was investigated. The superior properties of this catalyst were attributed to the combination of the nanosize ...A novel nanosized amorphous Ru-Fe-B/ZrO2 alloy catalyst for benzene selective hydrogenation to cyclohexene was investigated. The superior properties of this catalyst were attributed to the combination of the nanosize and the amorphous character as well as to its textural character. In addition, the concentration of zinc ions, the content of ZrO2 in the slurry, and the pretreatment of the catalyst were found to be effective in improving the activity and the selectivity of the catalyst.展开更多
Cyclohexanol is an important intermediate in the synthesis of Nylon-6 and plasticizers. In this work,cobalt oxide nanoparticles(NPs) supported on porous carbon(Co Ox@CN) were fabricated by one-pot method and the h...Cyclohexanol is an important intermediate in the synthesis of Nylon-6 and plasticizers. In this work,cobalt oxide nanoparticles(NPs) supported on porous carbon(Co Ox@CN) were fabricated by one-pot method and the hybrids could efficiently and selectively hydrogenate phenol to cyclohexanol with a high yield of 98%. The high catalytic performance of Co Ox@CN was associate with the high surface area(340 m2/g) and uniformly dispersed NPs. Furthurmore, by detailed analysing the relationship between catalytic activity and catalysts composition, it clearly indicated that the Co3O4 in Co Ox@CN played an important role for the adsorption and activation of phenol and the in situ gernerated Co was responsible for hydrogen adsorption and dissociation. These findings provide a fundamental insight into the real active sites in hydrogenation of phenol using Co-based catalysts.展开更多
Conversion of alkynes to alkenes by photocatalysis has inspired extensive interest but it is still challenging to obtain both high conversion and selectivity.Here we first demonstrate the photocatalytic conversion of ...Conversion of alkynes to alkenes by photocatalysis has inspired extensive interest but it is still challenging to obtain both high conversion and selectivity.Here we first demonstrate the photocatalytic conversion of phenylacetylene(PLE)to styrene(STE)with both high conversion and selectivity by using the titania(TiO2)supported platinum(Pt)as photocatalyst under 385 nm monochromatic light irradiation.It is demonstrated that the conversion rate of PLE is strongly dependent on the content of Pt cocatalyst loaded on the surface of TiO2.Based on our optimization,the conversion of PLE and the selectivity towards STE on the 1 wt%Pt/TiO2 photocatalyst can unexpectedly reach as high as 92.4%and 91.3%,respectively.The highly selective photocatalytic hydrogenation can well be extended to the conversion of other typical alkynes to alkenes,demonstrating the generality of selective hydrogenation of C≡C over the Pt/TiO2 photocatalyst.展开更多
The selective hydrogenation of phenol to cyclohexanone is an important process in the chemical industry.However,achieving high selectivity at high conversion rates is highly challenging,particularly under continuous r...The selective hydrogenation of phenol to cyclohexanone is an important process in the chemical industry.However,achieving high selectivity at high conversion rates is highly challenging,particularly under continuous reaction conditions.Here,we found that the presence of Na alkaline additives(NaX,X=CO3^2–,HCO^3–,or OH^–)on Pd/Al2O3 not only promoted the phenol conversion from 8.3%to>99%but also increased the cyclohexanone selectivity from 89%to>97%during the continuous hydrogenation of phenol on a fixed bed reactor.After 1200 h of continuous reaction,no activity or selectivity attenuation was observed and the turnover number was approximately 2.9×10^5.Density functional theory calculations,spectroscopic,and dynamics studies demonstrated that the addition of NaX greatly promoted phenol adsorption and hydrogen activation,thereby improving catalytic activity.Simultaneously,the formation of a“-C=O-Na-”intermediate inhibited the excessive hydrogenation and intermolecular coupling of cyclohexanone,leading to high selectivity.展开更多
Ru-Ce catalysts were prepared by a co-precipitation method.The effects of Ce precursors with different valences and Ce contents on the catalytic performance of Ru-Ce catalysts were investigated in the presence of ZnSO...Ru-Ce catalysts were prepared by a co-precipitation method.The effects of Ce precursors with different valences and Ce contents on the catalytic performance of Ru-Ce catalysts were investigated in the presence of ZnSO4.The Ce species in the catalysts prepared with different valences of the Ce precursors all exist as CeO2 on the Ru surface.The promoter CeO2alone could not improve the selectivity to cyclohexene of Ru catalysts.However,almost all the CeO2 in the catalysts could react with the reaction modifier ZnSO4 to form(Zn(OH)2)3(ZnSO4)(H2O)3 salt.The amount of the chemisorbed salt increased with the CeO2 loading,resulting in the decrease of the activity and the increase of the selectivity to cyclohexene of Ru catalyst.The Ru-Ce catalyst with the optimum Ce/Ru molar ratio of 0.19 gave a maximum cyclohexene yield of 57.4%.Moreover,this catalyst had good stability and excellent reusability.展开更多
Ru-based catalysts promoted with Mn and Zn were prepared by a co-precipitation method. In liquid-phase hydrogenation of benzene, the Ru-Mn-Zn catalysts exhibited superior catalytic performance to the catalysts promote...Ru-based catalysts promoted with Mn and Zn were prepared by a co-precipitation method. In liquid-phase hydrogenation of benzene, the Ru-Mn-Zn catalysts exhibited superior catalytic performance to the catalysts promoted with Zn or Mn alone. The optimum Mn/Zn molar ratio was determined to be 0.3. With the addition of 0.5 g NaOH, the Ru-Mn-Zn-0.3 catalyst, which was reduced at 150 ? C, afforded a cyclohexene selectivity of 81.1% at a benzene conversion of 60.2% at 5 min and a maximum cyclohexene yield of 59.9% at 20 min. Based on characterizations, the excellent performance of Ru-Mn-Zn catalyst was ascribed to the suitable pore structure, the appropriate reducibility and the homogenous chemical environment of the catalyst.展开更多
Although the selective hydrogenation ofα,β-unsaturated aldehyde to unsaturated alcohol(UOL)is an extremely important transformation,it is still a great challenge to achieve high selectivity to UOL due to thermodynam...Although the selective hydrogenation ofα,β-unsaturated aldehyde to unsaturated alcohol(UOL)is an extremely important transformation,it is still a great challenge to achieve high selectivity to UOL due to thermodynamic favoring of the C=C hydrogenation over the C=O hydrogenation.Herein,we report that iridium nanoclusters(Ir NCs)confined within hollow MIL-101(Fe)expresses satisfied reaction activity(93.9%)and high selectivity(96.2%)for the hydrogenation of cinnamaldehyde(CAL)to cinnamyl alcohol(COL)under 1 bar H;atmosphere and room temperature.The unique hollow structure of MIL-101(Fe)benefits for the fast transport of reactant,ensuring the comparable reaction activity and better recyclability of Ir@MIL-101(Fe)than the counterparts which Ir NCs were on the surface of MIL-101(Fe).Furthermore,The X-ray photoelectron spectroscopy data indicates the electropositive Ir NCs,owing to the electron transfer from Ir to MIL-101(Fe),can interact with oxygen lone pairs,and Fourier transform infrared spectrum shows the Lewis acid sites in MIL-101(Fe)can strongly interact with C=O bond,which contributes to a high selectivity for COL.This work suggests the considerable potential of synergetic effect between hollow MOFs and metal nanoclusters for selective hydrogenation reactions.展开更多
The catalytic activity of metal catalysts can be modulated by confinement within the channels of carbon nanotubes(CNTs).Here,we show that the product distribution of cinnamaldehyde hydrogenation can be modified by con...The catalytic activity of metal catalysts can be modulated by confinement within the channels of carbon nanotubes(CNTs).Here,we show that the product distribution of cinnamaldehyde hydrogenation can be modified by confinement of Ru nanoparticles in CNTs.A catalyst composed of Ru nanoparticles dispersed on the exterior walls of CNTs gave hydrocinnamaldehyde as product.In contrast,confinement of the Ru nanoparticles within CNT channels facilitated hydrogenation of C=O bonds and complete hydrogenation,and both cinnamyl alcohol and hydrocinnamyl alcohol formed in addition to hydrocinnamaldehyde.High‐resolution transmission electron microscopy,Raman spectroscopy,hydrogen temperature‐programmed reduction,and hydrogen temperature‐programmed desorption were used to investigate the characteristics of the catalysts.The results indicate that the different interactions between the confined Ru nanoparticles and the exterior and interior walls of the CNTs,as well as spatial restriction and enrichment within the narrow channels likely play important roles in modulation of the product distribution.展开更多
Anatase TiO_(2)nanospindles containing 89%exposed{101}facets(TIO_(2)-101)and nanosheets with 77%exposed{001}facets(TiO_(2)-001)were hydrothermally synthesized and used as supports for Pd catalysts.The effects of the T...Anatase TiO_(2)nanospindles containing 89%exposed{101}facets(TIO_(2)-101)and nanosheets with 77%exposed{001}facets(TiO_(2)-001)were hydrothermally synthesized and used as supports for Pd catalysts.The effects of the TiO_(2)materials on the catalytic performance of Pd/TiO_(2)-101 and Pd/TiO_(2)-001 catalysts were investigated in the selective hydrogenation of acetylene to polymer-grade ethylene.The PdfTiO_(2)-101 catalyst exhibited enhanced performance in terms of acetylene conversion and ethylene yield.To understand these effects,the catalysts were characterized by H_(2)temperature-programmed desorption(H_(2)-TPD),H_(2)temperature-programmed reduction(H=-TPR),transmission electron microscopy(TEM),pulse CO chemisorption,X-ray photoelectron spectroscopy(XPS),and thermogravimetric analysis(TGA).The TEM and CO chemisorption results confirmed that Pd nanoparticles(NPs)on the TiO_(2)-101 support had a smaller average particle size(1.53 nm)and a higher dispersion(15.95%)than those on the TiO_(2)-001 support(average particle size of 4.36 nm and dispersion of 9.06%).The smaller particle size and higher dispersion of Pd on the Pd/TiO_(2)-101 catalyst provided more reaction active sites,which contributed to the improved catalytic activity of this supported catalyst.展开更多
Halogenated anilines have a wide range of applications in the production of pharmaceuticals and agrochemical substances, and thus it is of great importance to develop highly active and selective catalysts for the hydr...Halogenated anilines have a wide range of applications in the production of pharmaceuticals and agrochemical substances, and thus it is of great importance to develop highly active and selective catalysts for the hydrogenation of halogenated nitrobenzenes. We approach this challenge by probing noble metal/non-noble metal oxide nanoparticles(NPs) catalysts. Carbon-supported Pd/SnO2catalysts were synthesized by the chemical reduction method, and their catalytic activity was evaluated by the hydrogenation reaction of 2,4-difluoronitrobenzene(DFNB) to the corresponding 2,4-difluoroaniline(DFAN), showing a remarkable synergistic effect of the Pd and SnO2 NPs. The as-prepared Pd/SnO2/C catalysts were characterized using TEM, XRD, H2 TPD and XPS techniques. Modifications to the electronic structure of the Pd atoms through the use of SnO2 led to the suppression of the hydrogenolysis of the C–F bond and the acceleration of nitrosobenzene(DFNSB) conversion and consequently, resulted in the inhibition of the formation of reactive by-products and may be responsible for the enhancements observed in selectivity.展开更多
基金the National Nature Science Foundation of China for Excellent Young Scientists Fund(32222058)Fundamental Research Foundation of CAF(CAFYBB2022QB001).
文摘Developing biomass platform compounds into high value-added chemicals is a key step in renewable resource utilization.Herein,we report porous carbon-supported Ni-ZnO nanoparticles catalyst(Ni-ZnO/AC)synthesized via low-temperature coprecipitation,exhibiting excellent performance for the selective hydrogenation of 5-hydroxymethylfurfural(HMF).A linear correlation is first observed between solvent polarity(E_(T)(30))and product selectivity within both polar aprotic and protic solvent classes,suggesting that solvent properties play a vital role in directing reaction pathways.Among these,1,4-dioxane(aprotic)favors the formation of 2,5-bis(hydroxymethyl)furan(BHMF)with 97.5%selectivity,while isopropanol(iPrOH,protic)promotes 2,5-dimethylfuran production with up to 99.5%selectivity.Mechanistic investigations further reveal that beyond polarity,proton-donating ability is critical in facilitating hydrodeoxygenation.iPrOH enables a hydrogen shuttle mechanism where protons assist in hydroxyl group removal,lowering the activation barrier.In contrast,1,4-dioxane,lacking hydrogen bond donors,stabilizes BHMF and hinders further conversion.Density functional theory calculations confirm a lower activation energy in iPrOH(0.60 eV)compared to 1,4-dioxane(1.07 eV).This work offers mechanistic insights and a practical strategy for solvent-mediated control of product selectivity in biomass hydrogenation,highlighting the decisive role of solvent-catalyst-substrate interactions.
文摘The selective hydrogenation ofα,β-unsaturated aldehydes/ketones enables precise control over product structures and properties by regulating hydrogen transport pathways and bond cleavage sequences to selectively reduce C=C or C=O bonds while preserving other functional groups within the molecule.This approach serves as a critical strategy for the directional synthesis of high-value molecules.However,achieving such selectivity remains challenging due to the thermodynamic equilibrium and kinetic competition between C=O and C=C bonds inα,β-unsaturated systems.Consequently,constructing precisely targeted catalytic systems is essential to overcome these limitations,offering both fundamental scientific significance and industrial application potential.Metal-organic frameworks(MOFs)and their derivatives have emerged as innovative platforms for designing such systems,owing to their programmable topology,tunable pore microenvironments,spatially controllable active sites,and modifiable electronic structures.This review systematically summarizes the research progress of MOF-based catalysts for selec-tive hydrogenation ofα,β-unsaturated aldehydes/ketones in the last decade,with emphasis on the design strategy,conformational relationship,and catalytic mechanism,aiming to provide new ideas for the design of targeted catalyt-ic systems for the selective hydrogenation ofα,β-unsaturated aldehydes/ketones.
基金supported by National Natural Science Foundation of China(22379131,22278049,22278049,and U24A20559)China Postdoctoral Science Foundation(2023M733216)+1 种基金Henan Science and Technology Department(242300421355)the Dalian High-Level Talent Innovation Program(2024RJ017).
文摘The aqueous-phase hydrogenation of furfural to furfuryl alcohol using non-noble metal catalysts is constrained by the low activity of catalysts,necessitating high temperatures and high hydrogen pressures,and posing challenges in controlling furfuryl alcohol selectivity.Herein,a Co nanoparticle catalyst supported on nitrogendoped carbon derived from MOFs is reported,which adopts a synergistic strategy to enhance catalytic perfor-mance.The nitrogen doping simultaneously promotes hydrogen spillover on the catalyst surface and reduces surface acidity,thereby suppressing acid-catalyzed side reactions.This dual function enables the selective hy-drogenation of-C=O groups to-CH_(2)OH groups in water under mild conditions.Furfural reached 98%con-version with 95%selectivity of furfuryl alcohol at 135℃ and under hydrogen pressure close to atmospheric(0.4 MPa)in 2 h.This study allows a low energy-consuming method for producing furfuryl alcohol from hemicellulose-derived furfural,and provides a promising strategy for the conversion of renewable biomassderived compounds into high value-added chemicals.
基金sponsored by the National Natural Science Foundation of China(Grant Nos.22308381 and 22522818)Science Foundation of China University of Petroleum-Beijing(Grant Nos.2462023QNXZ002 and 2462023QNXZ005)+1 种基金Beijing Nova Program(Grant No.20220484096)the National Key R&D Program of China(Grant No.2021YFA1501201).
文摘Hierarchical Ni/ZSM-22-SBA-15 meso-microporous catalysts(Ni/ZS-x)with different acid properties and diffusion characteristics(acid-diffusion)properties were synthesized successfully and applied to the production of high-quality jet fuel by the efficient one-step hydrogenation(hydrodeoxygenation,isomerization,and cracking)of oleic acid.The acid-diffusion properties of the catalysts are modulated by tuning the ZSM-22 seed content,and their effects on the hydrogenation reactions were investigated.Acid properties affect the extent of isomerization and cleavage reactions,whereas diffusion properties affect the accessibility of active centers.The balanced acid-diffusion properties are conducive to efficient hydrogenation reactions of oleic acid.The optimal Ni/ZS-3 exhibits the highest jet fuel yield(56.3%,340°C)and superior iso/n-alkane ratio(i/n=3.12)because of its well-balanced acid-diffusion properties.Besides,the possible hydrogenation mechanism of oleic acid is proposed.
基金China Postdoctoral Science Foundation (2023M733451)Dalian Innovation Team in Key Areas(2020RT06)Engineering Research Center for Key Aromatic Compounds and LiaoNing Key Laboratory,Liaoning Provincial Natural Science Foundation (Doctoral Research Start-up Fund 2024-BSBA-37)。
文摘Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of C=C over C=O.Herein,a novel Al_(2)O_(3)/C-u hybrid catalyst,composed of N-modified dendritic carbon networks supporting Al_(2)O_(3)nanoparticles,was successfully prepared via carbonizing the freeze-dried gel from spontaneous cross-linking of alginate,Al3+and urea.The obtained carbon-supported Al_(2)O_(3)hybrid catalyst has a high ratio (31%) of Al species in pentahedral-coordinated state.The introduction of urea enhances the surface N content,the ratio of pyrrolic N,and specific surface area of catalyst,leading to improved adsorption capacity of C=O and the accessibility of active sites.In the furfural hydrogenation reaction with isopropyl alcohol as hydrogen donor,Al_(2)O_(3)/C-u catalyst achieved a 90%conversion of furfural with 98.0% selectivity to furfuryl alcohol,outperforming that of commercial γ-Al_(2)O_(3).Moreover,Al_(2)O_(3)/C-u demonstrates excellent catalytic stability in the recycling tests attributed to the synergistic effect of abundant weak Lewis acid sites and the anchoring effect of the carbon network on Al_(2)O_(3)nanoparticles.This work provides an innovative and facile strategy for fabrication of carbon-supported Al_(2)O_(3)hybrid catalysts with rich AlVspecies,serving as a high selective hydrogenation catalyst through MPV reaction route.
文摘Pd/C catalysts were prepared by deposited Pd nanoparticles (NPs) on different carbon supports including activated carbon (AC), graphite oxide (GO), and reduced graphite oxide (rGO) using sol-immobilization method. Through transmission electron microscopy, powder X-ray di raction, and X-ray photoelectron spectroscopy, the role of the carbon supports for the catalytic performances of Pd/C catalysts was examined in selective hydrogenation of acetylene. The results indicate that Pd/AC exhibited higher activity and selectivity than Pd/GO and Pd/rGO in the gas phase selective hydrogenation of acetylene. Thermal and chemical treatment of AC supports also have some effect on the catalytic performance of Pd/AC catalysts. The differences in the activity and selectivity of various Pd/C catalysts were partly attributed to the metal-support interaction.
基金supported by the National Natural Science Foundation of China(21573031 and 21428301)the Fundamental Research Funds for the Central Universities(DUT15ZD106 and DUT15RC(4)09)~~
文摘A catalyst consisting of platinum nanoparticles on a ZIF-8 support(Pt@ZIF-8) was synthesized in a straightforward one-step procedure,by adding a nanostructured platinum sol during the formation of ZIF-8 at room temperature.Pt@ZIF-8 was highly porous and well crystallized.The Pt nanoparticles were well dispersed within the ZIF-8 support.In the hydrogenation of 1,4-butynediol,Pt@ZIF-8 exhibited high activity,excellent selectivity for 1,4-butenediol of greater than 94%,and reusability.The Pt@ZIF-8 catalyst did not require further additives.The favorable catalytic performance was attributed primarily to the modification of the ZIF-8 support by the platinum nanoparticles.
文摘The IB metal(Au,Ag and Cu)alloyed Pd single atom catalysts had been proved to be efficient in promoting the selectivity for hydrogenation of acetylene to ethylene.As a base metal in the same group as Pd,the Ni-based catalysts are also active for hydrogenation reactions.Herein,the effects of the IB metals on the Ni/SiO2 catalyst for the selective hydrogenation of acetylene were systematically studied.Different from the Pd/SiO2 catalyst,the monometallic Ni/SiO2 catalyst is not active at low temperatures.The addition of the IB metals to the Ni/SiO2 catalysts can greatly enhance the activity.Besides,the catalytic activity of the AuNix/SiO2 and CuNix/SiO2 catalysts increase with the reduction temperature,while the AgNix/SiO2 catalysts are not sensitive to the pretreatment temperature.The origin of the effect of the different IB metals on the Ni-based catalysts for selective hydrogenation of acetylene is discussed based on the characterizations by XRD,TPR and microcalorimetric measurements.
文摘An efficient heterogeneous catalyst,Pd@MIL‐101(Cr)‐NH2,is prepared through a direct pathway of anionic exchange followed by hydrogen reduction with amino‐containing MIL‐101as the host matrix.The composite is thermally stable up to350°C and the Pd nanoparticles uniformly disperse on the matal organic framework(MOF)support,which are attributed to the presence of the amino groups in the frameworks of MIL‐101(Cr)‐NH2.The selective hydrogenation of biomass‐based furfural to tetrahydrofurfuryl alcohol is investigated by using this multifunctional catalyst Pd@MIL‐101(Cr)‐NH2in water media.A complete hydrogenation of furfural is achieved at a low temperature of40°C with the selectivity of tetrahydrofurfuryl alcohol close to100%.The amine‐functionalized MOF improves the hydrogen bonding interactions between the intermediate furfuryl alcohol and the support,which is conducive for the further hydrogenation of furfuryl alcohol to tetrahydrofurfuryl alcohol in good coordination with the metal sites.
文摘The effect of La on the performance of a supported RuB amorphous alloy catalyst for benzene selective hydrogenation was studied by means of activity and selectivity tests, such as HRTEM, SAED, XPS, and XRD. The results show that the addition of La to RuB amorphous alloy catalyst can evidently increase the activity and improve the thermal stability of RuB amorphous alloy to refrain its crystallization. The promoting effect of La on the activity of RuB amorphous alloy catalyst is because of the high dispersion of the active components.
文摘A novel nanosized amorphous Ru-Fe-B/ZrO2 alloy catalyst for benzene selective hydrogenation to cyclohexene was investigated. The superior properties of this catalyst were attributed to the combination of the nanosize and the amorphous character as well as to its textural character. In addition, the concentration of zinc ions, the content of ZrO2 in the slurry, and the pretreatment of the catalyst were found to be effective in improving the activity and the selectivity of the catalyst.
基金Financial support from the key program supported by the Natural Science Foundation of Zhejiang Province, China (No. LZ18B060002)the National Natural Science Foundation of China (No. 21622308)+2 种基金the Specialized Research Fund for the Doctoral Program of Higher Education (No. J20130060)the Fundamental Research Funds for the Central Universitiesthe Program for Zhejiang Leading Team of S&T Innovation are greatly appreciated
文摘Cyclohexanol is an important intermediate in the synthesis of Nylon-6 and plasticizers. In this work,cobalt oxide nanoparticles(NPs) supported on porous carbon(Co Ox@CN) were fabricated by one-pot method and the hybrids could efficiently and selectively hydrogenate phenol to cyclohexanol with a high yield of 98%. The high catalytic performance of Co Ox@CN was associate with the high surface area(340 m2/g) and uniformly dispersed NPs. Furthurmore, by detailed analysing the relationship between catalytic activity and catalysts composition, it clearly indicated that the Co3O4 in Co Ox@CN played an important role for the adsorption and activation of phenol and the in situ gernerated Co was responsible for hydrogen adsorption and dissociation. These findings provide a fundamental insight into the real active sites in hydrogenation of phenol using Co-based catalysts.
基金supported by the National Natural Science Foundation of China(21633009)Dalian Science Foundation for Distinguished Young Scholars(2017RJ02)the Liaoning Revitalization Talents Program(XLYC1807241)~~
文摘Conversion of alkynes to alkenes by photocatalysis has inspired extensive interest but it is still challenging to obtain both high conversion and selectivity.Here we first demonstrate the photocatalytic conversion of phenylacetylene(PLE)to styrene(STE)with both high conversion and selectivity by using the titania(TiO2)supported platinum(Pt)as photocatalyst under 385 nm monochromatic light irradiation.It is demonstrated that the conversion rate of PLE is strongly dependent on the content of Pt cocatalyst loaded on the surface of TiO2.Based on our optimization,the conversion of PLE and the selectivity towards STE on the 1 wt%Pt/TiO2 photocatalyst can unexpectedly reach as high as 92.4%and 91.3%,respectively.The highly selective photocatalytic hydrogenation can well be extended to the conversion of other typical alkynes to alkenes,demonstrating the generality of selective hydrogenation of C≡C over the Pt/TiO2 photocatalyst.
基金supported by the National Natural Science Foundation of China (21622308)Key Program Supported by the Natural Science Foundation of Zhejiang Province, China (LZ18B060002)the Fundamental Research Funds for the Central Universities (2017XZZX002-16)~~
文摘The selective hydrogenation of phenol to cyclohexanone is an important process in the chemical industry.However,achieving high selectivity at high conversion rates is highly challenging,particularly under continuous reaction conditions.Here,we found that the presence of Na alkaline additives(NaX,X=CO3^2–,HCO^3–,or OH^–)on Pd/Al2O3 not only promoted the phenol conversion from 8.3%to>99%but also increased the cyclohexanone selectivity from 89%to>97%during the continuous hydrogenation of phenol on a fixed bed reactor.After 1200 h of continuous reaction,no activity or selectivity attenuation was observed and the turnover number was approximately 2.9×10^5.Density functional theory calculations,spectroscopic,and dynamics studies demonstrated that the addition of NaX greatly promoted phenol adsorption and hydrogen activation,thereby improving catalytic activity.Simultaneously,the formation of a“-C=O-Na-”intermediate inhibited the excessive hydrogenation and intermolecular coupling of cyclohexanone,leading to high selectivity.
基金supported by the National Nature Science Foundation of China(21273205)the Innovation Found for Technology Based Firms of China(10C26214104505)+1 种基金the Chinese Post-doctorate Science Fund 51th batch of surface subsidizes(2012M511125)the Scientific Research Foundation of Graduate School of Zhengzhou University
文摘Ru-Ce catalysts were prepared by a co-precipitation method.The effects of Ce precursors with different valences and Ce contents on the catalytic performance of Ru-Ce catalysts were investigated in the presence of ZnSO4.The Ce species in the catalysts prepared with different valences of the Ce precursors all exist as CeO2 on the Ru surface.The promoter CeO2alone could not improve the selectivity to cyclohexene of Ru catalysts.However,almost all the CeO2 in the catalysts could react with the reaction modifier ZnSO4 to form(Zn(OH)2)3(ZnSO4)(H2O)3 salt.The amount of the chemisorbed salt increased with the CeO2 loading,resulting in the decrease of the activity and the increase of the selectivity to cyclohexene of Ru catalyst.The Ru-Ce catalyst with the optimum Ce/Ru molar ratio of 0.19 gave a maximum cyclohexene yield of 57.4%.Moreover,this catalyst had good stability and excellent reusability.
文摘Ru-based catalysts promoted with Mn and Zn were prepared by a co-precipitation method. In liquid-phase hydrogenation of benzene, the Ru-Mn-Zn catalysts exhibited superior catalytic performance to the catalysts promoted with Zn or Mn alone. The optimum Mn/Zn molar ratio was determined to be 0.3. With the addition of 0.5 g NaOH, the Ru-Mn-Zn-0.3 catalyst, which was reduced at 150 ? C, afforded a cyclohexene selectivity of 81.1% at a benzene conversion of 60.2% at 5 min and a maximum cyclohexene yield of 59.9% at 20 min. Based on characterizations, the excellent performance of Ru-Mn-Zn catalyst was ascribed to the suitable pore structure, the appropriate reducibility and the homogenous chemical environment of the catalyst.
基金supported by National Key R&D Program of China(No.2018YFA0108300)the Overseas High-level Talents Plan of China and Guangdong Province+3 种基金the 100 Talents Plan Foundation of Sun Yat-sen Universitythe Fundamental Research Funds for the Central Universitiesthe Program for Guangdong Introducing Innovative and Entrepreneurial Teams(No.2017ZT07C069)the NSFC Projects(Nos.21905315 and 22075321)。
文摘Although the selective hydrogenation ofα,β-unsaturated aldehyde to unsaturated alcohol(UOL)is an extremely important transformation,it is still a great challenge to achieve high selectivity to UOL due to thermodynamic favoring of the C=C hydrogenation over the C=O hydrogenation.Herein,we report that iridium nanoclusters(Ir NCs)confined within hollow MIL-101(Fe)expresses satisfied reaction activity(93.9%)and high selectivity(96.2%)for the hydrogenation of cinnamaldehyde(CAL)to cinnamyl alcohol(COL)under 1 bar H;atmosphere and room temperature.The unique hollow structure of MIL-101(Fe)benefits for the fast transport of reactant,ensuring the comparable reaction activity and better recyclability of Ir@MIL-101(Fe)than the counterparts which Ir NCs were on the surface of MIL-101(Fe).Furthermore,The X-ray photoelectron spectroscopy data indicates the electropositive Ir NCs,owing to the electron transfer from Ir to MIL-101(Fe),can interact with oxygen lone pairs,and Fourier transform infrared spectrum shows the Lewis acid sites in MIL-101(Fe)can strongly interact with C=O bond,which contributes to a high selectivity for COL.This work suggests the considerable potential of synergetic effect between hollow MOFs and metal nanoclusters for selective hydrogenation reactions.
基金supported by the National Natural Science Foundation of China (21621063,21425312)~~
文摘The catalytic activity of metal catalysts can be modulated by confinement within the channels of carbon nanotubes(CNTs).Here,we show that the product distribution of cinnamaldehyde hydrogenation can be modified by confinement of Ru nanoparticles in CNTs.A catalyst composed of Ru nanoparticles dispersed on the exterior walls of CNTs gave hydrocinnamaldehyde as product.In contrast,confinement of the Ru nanoparticles within CNT channels facilitated hydrogenation of C=O bonds and complete hydrogenation,and both cinnamyl alcohol and hydrocinnamyl alcohol formed in addition to hydrocinnamaldehyde.High‐resolution transmission electron microscopy,Raman spectroscopy,hydrogen temperature‐programmed reduction,and hydrogen temperature‐programmed desorption were used to investigate the characteristics of the catalysts.The results indicate that the different interactions between the confined Ru nanoparticles and the exterior and interior walls of the CNTs,as well as spatial restriction and enrichment within the narrow channels likely play important roles in modulation of the product distribution.
文摘Anatase TiO_(2)nanospindles containing 89%exposed{101}facets(TIO_(2)-101)and nanosheets with 77%exposed{001}facets(TiO_(2)-001)were hydrothermally synthesized and used as supports for Pd catalysts.The effects of the TiO_(2)materials on the catalytic performance of Pd/TiO_(2)-101 and Pd/TiO_(2)-001 catalysts were investigated in the selective hydrogenation of acetylene to polymer-grade ethylene.The PdfTiO_(2)-101 catalyst exhibited enhanced performance in terms of acetylene conversion and ethylene yield.To understand these effects,the catalysts were characterized by H_(2)temperature-programmed desorption(H_(2)-TPD),H_(2)temperature-programmed reduction(H=-TPR),transmission electron microscopy(TEM),pulse CO chemisorption,X-ray photoelectron spectroscopy(XPS),and thermogravimetric analysis(TGA).The TEM and CO chemisorption results confirmed that Pd nanoparticles(NPs)on the TiO_(2)-101 support had a smaller average particle size(1.53 nm)and a higher dispersion(15.95%)than those on the TiO_(2)-001 support(average particle size of 4.36 nm and dispersion of 9.06%).The smaller particle size and higher dispersion of Pd on the Pd/TiO_(2)-101 catalyst provided more reaction active sites,which contributed to the improved catalytic activity of this supported catalyst.
基金supported by the National Natural Science Foundation of China (Nos. 20976164, 21176221 and 21136001)National Basic Research Program of China (973 Program) (Nos. 2011CB710803 and 2013CB733500)
文摘Halogenated anilines have a wide range of applications in the production of pharmaceuticals and agrochemical substances, and thus it is of great importance to develop highly active and selective catalysts for the hydrogenation of halogenated nitrobenzenes. We approach this challenge by probing noble metal/non-noble metal oxide nanoparticles(NPs) catalysts. Carbon-supported Pd/SnO2catalysts were synthesized by the chemical reduction method, and their catalytic activity was evaluated by the hydrogenation reaction of 2,4-difluoronitrobenzene(DFNB) to the corresponding 2,4-difluoroaniline(DFAN), showing a remarkable synergistic effect of the Pd and SnO2 NPs. The as-prepared Pd/SnO2/C catalysts were characterized using TEM, XRD, H2 TPD and XPS techniques. Modifications to the electronic structure of the Pd atoms through the use of SnO2 led to the suppression of the hydrogenolysis of the C–F bond and the acceleration of nitrosobenzene(DFNSB) conversion and consequently, resulted in the inhibition of the formation of reactive by-products and may be responsible for the enhancements observed in selectivity.