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
A CuSiAlO_(x)catalyst was prepared through infrared-heating calcination and employed to catalyze vapor furfural(FFR)hydrogenation in a fixed-bed reactor.Its catalytic performance was systematically evaluated and compa...A CuSiAlO_(x)catalyst was prepared through infrared-heating calcination and employed to catalyze vapor furfural(FFR)hydrogenation in a fixed-bed reactor.Its catalytic performance was systematically evaluated and compared to that of a catalyst derived from the same precursor but calcined using an electric oven.The hydrogenation tests were performed at temperatures varying in 140~180℃,H_(2)/FFR(mol/mol)ratios in 4:1~8:1,and liquid hourly space velocity(LHSVs)in 0.6~1.0 h^(-1).The catalyst CuSiAlO_(x)-IH(prepared by infrared-heating calcination)demonstrated higher FFR conversion than CuSiAlO_(x)-EH(prepared by electric-oven heating)did.Under the conditions of a H_(2)/FFR ratio of 6:1,a temperature of 140℃,and an LHSV of 0.6 h^(-1),the CuSiAlO_(x)-IH catalyst achieved a 99.70%FFR conversion and 95.72%selectivity to furfur alcohol(FOL)in a continuous test for 18 h.This time duration with good stability was twice longer than that enabled by CuSiAlO_(x)-EH.Characterization of the fresh,reduced,and spent catalysts revealed that the catalyst CuSiAlO_(x)-IH,compared to CuSiAlO_(x)-EH,possessed more Cu defects,a higher BET surface area,a smaller average size,and the narrower size distribution of active-species particles.These structural advantages thus rendered the CuSiAlO_(x)-IH catalyst superior in its catalysis of the FFR hydrogenation reactions.展开更多
Oat husks,a byproduct of oat milling operations with limited economic value,present a promising feedstock for biorefinery processes due to their chemical composition.This study investigates the conversion of C5 carboh...Oat husks,a byproduct of oat milling operations with limited economic value,present a promising feedstock for biorefinery processes due to their chemical composition.This study investigates the conversion of C5 carbohydrates in oat husks into furfural through hydrothermal pretreatment using various phosphate-based catalysts,including H_(3)PO_(4),NH_(4)H_(2)PO_(4),NaH_(2)PO_(4),KH_(2)PO_(4),K_(2)HPO_(4) and K_(3)PO_(4) as catalyst.The catalysts’effectiveness in promoting furfural production was evaluated under identical hydrothermal conditions(treatment time for 60 min at a constant temperature of 170℃ and a catalyst amount).Continuous water steam was used to strip furfural from the reaction zone and minimize its degradation.Results indicated that H_(3)PO_(4) was the most effective catalyst,achieving a furfural yield of 13.99 wt.%,which corresponds to approximately 57%of the theoretical yield.NH4H2PO4 also showed moderate effectiveness,while sodium and potassium phosphate salts were significantly less effective.A scanning electron microscope analysis shows that catalysts with lower pH may disrupt the oat husks external layer thus providing a higher C5 carbohydrates conversion rate into furfural.The chemical complexity of oat husk contributes to side reactions between its carbohydrates and lignin during the hydrothermal treatment.This results in an increase in acid-insoluble lignin and inorganic matter in the oat husk lignocellulosic residue,which can reduce the effectiveness of further cellulose saccharification by enzymatic hydrolysis.展开更多
Transition-state shape selectivity plays a crucial role in catalytic systems where reactants and products exhibit comparable molecular dimensions,as it restricts the accessible configuration space of reaction intermed...Transition-state shape selectivity plays a crucial role in catalytic systems where reactants and products exhibit comparable molecular dimensions,as it restricts the accessible configuration space of reaction intermediates.Herein,we designed a Cu@MFI catalyst by encapsulating Cu active sites within the well-defined micropores of MFI zeolite through a pore confinement strategy.This architecture preserves the zeolite framework integrity while maintaining unhindered internal mass transport,thereby enabling precise spatial control over transition-state configurations.Employing furfural hydrogenation as a probe reaction,the metal-zeolite synergy in Cu@MFI endowed the catalyst with exceptional activity(100%furfural conversion)and quantitative selectivity(100%furfuryl alcohol)at 70℃,sustained across a broad temperature window.Mechanistic studies reveal that the transition-state shape selectivity effectively prevented H2O interaction with the furan ring,offering valuable insights for other reaction systems seeking to exploit shape selectivity for specific transformations.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
The electrocatalytic furfural oxidation reaction(FFOR)represents an economical and promising technology to replace conventional oxygen evolution reaction,enabling the co-production of high value chemicals and H_(2).Re...The electrocatalytic furfural oxidation reaction(FFOR)represents an economical and promising technology to replace conventional oxygen evolution reaction,enabling the co-production of high value chemicals and H_(2).Regulating the adsorption of furfural(FF)and OH^(-)species holds paramount importance in enhancing the overall performance.Herein,we have developed a unique CuO catalyst enriched with oxygen vacancies(O_(v)-CuO)resulting from the electrochemical reconstruction ofα-Cu_(2)S,which demonstrates exceptional FFOR performance,with a conversion of 95.3%,near-perfect selectivity and Faraday efficiency(FE)for furoic acid(FA)at 1.475 V vs.RHE.The study provides detailed comparison of the structural evolution of different sulfide precatalysts and their impact on FFOR.Furthermore,it delves into the structure-activity relationship through a combination of characterization and theoretical calculations.The O_(v)-CuO not only enhances OH^(-)adsorption,changes the rate-determining step,but also reduces the reaction energy barrier toward FFOR.Additionally,a much lower cell voltage is required to coproduce FA and hydrogen in the two-electrode co-electrolysis system.This work would provide valuable insights into the reaction mechanism of FFOR on Cu based catalysts and establish guidelines for designing defective electrocatalysts for biomass conversion.展开更多
The reductive transformation of furfural （FAL） into furfuryl alcohol （FOL） is an attractive route for the use of renewable bio‐sources but it suffers from the heavy use of H2. We describe here a highly efficient ...The reductive transformation of furfural （FAL） into furfuryl alcohol （FOL） is an attractive route for the use of renewable bio‐sources but it suffers from the heavy use of H2. We describe here a highly efficient reduction protocol for converting aqueous FAL to FOL. A single phase rutile TiO2 support with a gold catalyst （Au/TiO2‐R） that used CO/H2O as the hydrogen source catalyze this reduction efficiently under mild conditions. By eliminating the consumption of fossil fuel‐derived H2, our pro‐cess has the benefit afforded by using CO as a convenient and cost competitive reducing reagent.展开更多
Photocatalytic hydrogenation of furfural offers an ideal method for selective biomass upgrading into value-added chemicals or fuel additives under mild conditions. However, it is still challenging to control the produ...Photocatalytic hydrogenation of furfural offers an ideal method for selective biomass upgrading into value-added chemicals or fuel additives under mild conditions. However, it is still challenging to control the product selectivity due to side reactions of functional groups and reactive radical intermediates.Herein, photocatalytic transfer hydrogenation of furfural was studied using the TiO_(2)-based photocatalysts with alcohols as both the solvent and hydrogen donor. Ultralow loading metal supported on TiO_(2),together with adding a small amount of water in the system, were demonstrated to greatly increase the selectivity of furfuryl alcohol product. Electron paramagnetic resonance(EPR), ultraviolet-visible spectroscopy(UV-Vis) and photoluminescence(PL) measurements gave evidence that ultralow loading Pt or Pd on TiO_(2)increase the oxygen vacancy concentration and the photogenerated charge separation efficiency, which accelerates the photocatalytic reduction of furfural. In situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS) and mechanistic studies confirmed that photogenerated holes and electrons are active species, with dissociatively adsorbed methanol being directly oxidized by holes,furfural hydrogenated by protons and electrons and H_(2)O modifying the intermediate diffusion which contributes to high selectivity of furfuryl alcohol. This work demonstrates a simple approach to design photocatalysts and tune product selectivity in biomass valorization.展开更多
From both fundamental and practical perspectives, the production of chemicals from biomass re-sources using high-efficiency non-precious metal catalysts is important. However, many processes require addition of stoic...From both fundamental and practical perspectives, the production of chemicals from biomass re-sources using high-efficiency non-precious metal catalysts is important. However, many processes require addition of stoichiometric or excess quantities of base, which leads to high energy consump-tion, leaching problems, and side reactions. In this study, we investigated the high-efficiency oxida-tive esterification of furfural to methylfuroate by molecular oxygen with a Co-N-C/MgO catalyst. The catalyst was prepared by direct pyrolysis of a cobalt（Ⅱ） phenanthroline complex on MgO at 800℃ under N2 atmosphere. From furfural, 93.0% conversion and 98.5% selectivity toward methylfuroate were achieved under 0.5 MPa O2 with reaction at 100 ℃ for 12 h without a basic additive. The con-version and selectivity were much higher than those obtained with cobalt catalysts produced by pyrolysis of a cobalt（Ⅱ） phenanthroline complex on activated carbon or typical basic supports, in-cluding NaX, NaY, and CaO. X-ray photoelectron spectroscopy, X-ray diffraction, transmission elec-tron microscopy, and experimental results revealed that the high efficiency of Co-N-C/MgO for pro-duction of methylfuroate was closely related to the cobalt-nitrogen-doped carbon species and its catalytic ability in hydrogen abstraction. In contrast, Co-N-C（HCl） that synthesized by removing MgO with HCl from Co-N-C/MgO, as the catalyst produced mainly an acetal as a condensation prod-uct, and chloride ions had a negative effect on the oxidative esterification. Although the catalytic performance of the cobalt-nitrogen-doped carbon species was greatly affected by HCl treatment, it could be recovered to a great extent by addition of MgO. Moreover, changes in the oxygen pressure hardly affected the oxidative esterification of furfural with Co-N-C/MgO. This study not only pro-vides an effective approach to prepare methylfuroate, but also for designing high-performance non-precious metal catalysts for the oxidative esterification of biomass-derived compounds.展开更多
Renewable resources based polymers provides a sustainable alternative to petroleum derived polymeric materials.As a part of our series on synthesis of vanillin based renewable polymers,we report the synthesis of poly(...Renewable resources based polymers provides a sustainable alternative to petroleum derived polymeric materials.As a part of our series on synthesis of vanillin based renewable polymers,we report the synthesis of poly(hydrovanilloin-furfural)[poly(HVL-Fur)]and poly(hydrovanilloin–5-hydromethylfurfural)[poly(HVL-5-HMF)].Vanillin was dimerized to a mixtures of meso/DL-hydrovanilloins with 94%meso product by electrochemical reductive coupling in aqueous sodium hydroxide using lead electrodes in quantitative yield.Then sodium hydroxide catalyzed condensation of hydrovanilloin with furfural in water at 80℃for 72 h was used to synthesize poly(HVL-Fur)with Mw=8600 g mol^(−1),PDI=1.28 in 78%yield.Similarly,condensation of hydrovanilloin with 5-hydroxymethylfurfural at 80℃for 48 h produced poly(HVL-5-HMF)with Mw=12,100 g mol−1,PDI=1.27 in 68%yield.poly(HVL-Fur)and poly(HVL-5-HMF)showed similar Tg values of 59℃and 60℃,respectively;whereas melting behaviors are dissimilar with Tm 171℃–173℃and 148℃–182℃,respectively.展开更多
The gas-phase hydrogenation of furfural to furfuralcohol over Cr-free Cu-based catalysts has attracted increasing attention due to its environmentally friendly nature and mild operating conditions.Although reduced pur...The gas-phase hydrogenation of furfural to furfuralcohol over Cr-free Cu-based catalysts has attracted increasing attention due to its environmentally friendly nature and mild operating conditions.Although reduced pure nano-sized CuO exhibits complete furfural hydrogenation and nearly 100%furfuralcohol selectivity,it suffers from rapid deactivation caused by sintering.In this study,we conducted comparative investigations on the catalytic performance and stability of two Cu-based catalysts:90%CuO-10%SiO_(2) and 90%CuO-5%CaO-5%SiO_(2),in the gas-phase furfural hydrogenation.The reaction is carried out under various conditions,including temperatures ranging from 120 to 170℃,LHSVs of 1 to 2.2 h^(-1),and H_(2) to furfural molar ratios of 3.5 to 12.5.The results indicate that under optimal conditions,the Ca-modified catalyst achieves nearly complete furfural conversion and almost 100%furfuralcohol selectivity for a test duration of 31 h.In contrast,the unmodified catalyst exhibits stable performance for only seven hours despite the similar initial performance.XRD analysis confirms that the gradual deactivation of both catalysts is attributed to the oxidation of reduced metallic Cu sites to Cu oxides.Further characterizations of the two spent catalysts using HRTEM and XPS analyses,along with DFT calculations,suggest that the presence of Ca in Cu lattices prevents the loss of electrons from low-valence Cu sites or the reduced metallic Cu sites,thus inhibiting their oxidation to high-valence Cu oxides.This phenomenon contributes to suppressing the deactivation of Cu-catalysts in the gas-phase furfural hydrogenation process.展开更多
A series of Cu-Mg-Al hydrotalcites derived oxides with a(Cu+Mg)/Al mole ratio of 3 and varied Cu/Mg mole ratio(from 0.07 to 0.30) were prepared by co-precipitation and calcination methods, then they were introduced to...A series of Cu-Mg-Al hydrotalcites derived oxides with a(Cu+Mg)/Al mole ratio of 3 and varied Cu/Mg mole ratio(from 0.07 to 0.30) were prepared by co-precipitation and calcination methods, then they were introduced to the hydrogenation of furfural in aqueous-phase. Effects of Cu/Mg mole ratio, reaction temperature, initial hydrogen pressure, reaction time and catalyst amount on the conversion rate of furfural as well as the selectivity toward desired product cyclopentanol were systematically investigated. The conversion of furfural over calcined hydrotalcite catalyst with a Cu/Mg mole ratio of 0.2 was up to 98.5% when the reaction was carried out under 140 ?C and the initial hydrogen pressure of 4 MPa for 10 h, while the selectivity toward cyclopentanol was up to 94.8%. The catalysts were characterized by XRD and SEM. XRD diffraction of all the samples showed characteristic pattern of hydrotalcite with varied peak intensity as a result of different Cu content. The catalytic activity was improved gradually with the increase of Cu component in the hydrotalcite.展开更多
As an industrial byproduct of oil refining,furfural extract oil from reduced-pressure route Ⅱ with high aromatic content was used to prepare heat-resistant condensed polynuclear aromatic（COPNA） resin for the first ...As an industrial byproduct of oil refining,furfural extract oil from reduced-pressure route Ⅱ with high aromatic content was used to prepare heat-resistant condensed polynuclear aromatic（COPNA） resin for the first time.The basic properties of furfural extract oil and the resultant COPNA resin were characterized by infrared spectroscopy（FT-IR）,nuclear magnetic resonance spectroscopy（1H-NMR）,thermogravimetric analysis（TGA） and elemental analysis（EA）.The result showed that heat treated furfural extract oil was successfully used for the synthesis of heat-resistant COPNA resin.The average structural parameters of raw materials and prepared resin were calculated by the improved Brown-Ladner method,and the averaged molecular structure of the resin was obtained.The reaction mechanism for the synthesis of COPNA resin was suggested as an acid-catalyzed positive ion type polymerization.展开更多
Tandem catalysis for the hydrogenation rearrangement of furfural(FA)provides an attractive solution for manufacturing cyclopentanone(CPO)from renewable biomass resources.The Cu-Ni/Al-MCM-41 catalyst was synthesized an...Tandem catalysis for the hydrogenation rearrangement of furfural(FA)provides an attractive solution for manufacturing cyclopentanone(CPO)from renewable biomass resources.The Cu-Ni/Al-MCM-41 catalyst was synthesized and afforded excellent catalytic performance with 99.0%conversion and 97.7%selectivity to CPO in a near-neutral solution under 2.0 MPa H2 at 160℃ for 5 h,much higher than those on other molecular sieve supports including MCM-41,SBA-15,HY,and ZSM-5.A small amount of Al highly dispersed in MCM-41 plays an anchoring role and ensures the formation of highly dispersed CuNi bimetallic nanoparticles(NPs).The remarkably improved catalytic performance may be attributed to the bimetallic synergistic and charge transfer effects.In addition,the initial FA concentration and the aqueous system pH required precise control to minimize polymerization and achieve high selectivity of CPO.Fourier transform infrared spectroscopy and mass spectra results indicated that polymerization was sensitive to pH values.Under acidic conditions,FA and intermediate furfuryl alcohol polymerize,while the intermediate 4-hydroxy-2-cyclopentenone mainly polymerizes under alkaline conditions,blocking the cascade of multiple reactions.Therefore,near-neutral conditions are most suitable for minimizing the impact of polymerization.This study provides a useful solution for the current universal problems of polymerization side reactions and low carbon balance for biomass conversion.展开更多
Spinel ferrites NiFeOsupported Ru catalysts have been prepared via a simple sol–gel route and applied for converting biomass-derived furfural to 2-methylfuran. The as-prepared catalysts were characterized by thermogr...Spinel ferrites NiFeOsupported Ru catalysts have been prepared via a simple sol–gel route and applied for converting biomass-derived furfural to 2-methylfuran. The as-prepared catalysts were characterized by thermogravimetric analysis（TG）, Nadsorption–desorption, X-ray diffraction（XRD）, scanning electronic microscopy（SEM）, and X-ray photoelectron spectroscopy（XPS）. Results showed that the catalysts had well-dispersed Ru active sites and large surface area for calcination temperature ranging from 300 to 500 ℃. The conversion of biomass-derived furfural into 2-methylfuran was conducted over Ru/NiFeOthrough catalytic transfer hydrogenation in liquid-phase with 2-propanol as the hydrogen source. A significantly enhanced activity and increased 2-methylfuran yield have been achieved in this study. Under mild conditions（180 ℃ and 2.1 MPa N）, the conversion of furfural exceeds 97% and 2-methylfuran yield was up to 83% over the catalyst containing 8 wt% Ru. After five repeated uses, the catalytic activity and the corresponding product yield remained almost unchanged. The excellent catalytic activity and recycling performance provide a broad prospects for various practical applications.展开更多
To solve soil shortage in reclaiming subsided land of coal mines, the principal chemical properties of artificial soil formed by mixing organic furfural residue and inorganic fly ash were examined. The results indicat...To solve soil shortage in reclaiming subsided land of coal mines, the principal chemical properties of artificial soil formed by mixing organic furfural residue and inorganic fly ash were examined. The results indicated that the artificial soil was suitable for agriculture use after irrigation and desalination, the available nutrients in the artificial soil could satisfy the growth demand of plants, and the pH tended to the neutrality.展开更多
Phosphoric acid treated niobic acid(NbP)was used for the dehydration of xylose to furfural in biphasic solvent system,which was found to exhibit the best performance among the tested catalysts.The excellent performanc...Phosphoric acid treated niobic acid(NbP)was used for the dehydration of xylose to furfural in biphasic solvent system,which was found to exhibit the best performance among the tested catalysts.The excellent performance of NbP could be explained by the better synergistic cooperation between Bro¨nsted and Lewis acid sites.Moreover,NbP showed good stability and no obvious deactivation or leaching of Nb could be observed after six continuous recycles.展开更多
An environmentally benign processing approach for furfural production from xylose and xylan under very mild conditions（353–373 K） was developed with the addition of metal chlorides in ChCl–oxalic acid（a deep eute...An environmentally benign processing approach for furfural production from xylose and xylan under very mild conditions（353–373 K） was developed with the addition of metal chlorides in ChCl–oxalic acid（a deep eutectic solvent（DES）） synthesized from cheap and renewable starting materials）. ChCl–oxalic acid acted as both a Br？nsted acid catalyst and a reaction medium in this catalytic route. In addition, a biphasic system with methyl isobutyl ketone as an extracting reagent（DES/MIBK） to further increase furfural yield was also proposed. This processing approach for producing furfural eliminated the large energy consumption for high pressure saturated steam and the generation of acidic effluent, which was very difficult to handle. The whole catalytic system was more environmentally friendly compared with the commercial process for furfural production.展开更多
Furfural is an important inhibitor in ethanol fermentation process using lignocellulosic hydrolysates as raw materials. In order to find out the furfural concentration range in which furfural inhibits the fermentation...Furfural is an important inhibitor in ethanol fermentation process using lignocellulosic hydrolysates as raw materials. In order to find out the furfural concentration range in which furfural inhibits the fermentation process, we used one strain Saccharomyces kluyveri selected from soil and cultured in several different furfural content media under low glucose concentration condition. Experiment results showed that microorganism growth was stimulated and dry cell weight decreased when furfural concentration in the medium was 0.25 mg/ml. Furfural had negative effect on cell growth when its concentration was above 1.00 mg/ml. At the same time, the strain growed better and had a higher glucose consumption rate in 5% original glucose concentration condition than in 3% original glucose concentration condition. The results showed that appropriate exaltation of original glucose concentration in stalk hydrolysates will increase the strain resistance to furfural.展开更多
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supported by Youth Fund of National Natural Science Foundation of China(NO.22108175)Natural Science Foundation of Liaoning province(2021-NLTS-12-09)+2 种基金Liaoning Innovation Talents Program in University(Liao[2020]389)Liaoning Revitalization Tal-ents Program(XLYC1907029)Shenyang Young and Middle-aged Sci-ence&Technology Talents Program(RC210365).
文摘A CuSiAlO_(x)catalyst was prepared through infrared-heating calcination and employed to catalyze vapor furfural(FFR)hydrogenation in a fixed-bed reactor.Its catalytic performance was systematically evaluated and compared to that of a catalyst derived from the same precursor but calcined using an electric oven.The hydrogenation tests were performed at temperatures varying in 140~180℃,H_(2)/FFR(mol/mol)ratios in 4:1~8:1,and liquid hourly space velocity(LHSVs)in 0.6~1.0 h^(-1).The catalyst CuSiAlO_(x)-IH(prepared by infrared-heating calcination)demonstrated higher FFR conversion than CuSiAlO_(x)-EH(prepared by electric-oven heating)did.Under the conditions of a H_(2)/FFR ratio of 6:1,a temperature of 140℃,and an LHSV of 0.6 h^(-1),the CuSiAlO_(x)-IH catalyst achieved a 99.70%FFR conversion and 95.72%selectivity to furfur alcohol(FOL)in a continuous test for 18 h.This time duration with good stability was twice longer than that enabled by CuSiAlO_(x)-EH.Characterization of the fresh,reduced,and spent catalysts revealed that the catalyst CuSiAlO_(x)-IH,compared to CuSiAlO_(x)-EH,possessed more Cu defects,a higher BET surface area,a smaller average size,and the narrower size distribution of active-species particles.These structural advantages thus rendered the CuSiAlO_(x)-IH catalyst superior in its catalysis of the FFR hydrogenation reactions.
基金funded by the Latvian State Institute of Wood Chemistry Bioeconomic Research Grant No.09-24 titled“Selective Valorization of Lignocellulosic Biomass(SeVaLi)”.
文摘Oat husks,a byproduct of oat milling operations with limited economic value,present a promising feedstock for biorefinery processes due to their chemical composition.This study investigates the conversion of C5 carbohydrates in oat husks into furfural through hydrothermal pretreatment using various phosphate-based catalysts,including H_(3)PO_(4),NH_(4)H_(2)PO_(4),NaH_(2)PO_(4),KH_(2)PO_(4),K_(2)HPO_(4) and K_(3)PO_(4) as catalyst.The catalysts’effectiveness in promoting furfural production was evaluated under identical hydrothermal conditions(treatment time for 60 min at a constant temperature of 170℃ and a catalyst amount).Continuous water steam was used to strip furfural from the reaction zone and minimize its degradation.Results indicated that H_(3)PO_(4) was the most effective catalyst,achieving a furfural yield of 13.99 wt.%,which corresponds to approximately 57%of the theoretical yield.NH4H2PO4 also showed moderate effectiveness,while sodium and potassium phosphate salts were significantly less effective.A scanning electron microscope analysis shows that catalysts with lower pH may disrupt the oat husks external layer thus providing a higher C5 carbohydrates conversion rate into furfural.The chemical complexity of oat husk contributes to side reactions between its carbohydrates and lignin during the hydrothermal treatment.This results in an increase in acid-insoluble lignin and inorganic matter in the oat husk lignocellulosic residue,which can reduce the effectiveness of further cellulose saccharification by enzymatic hydrolysis.
文摘Transition-state shape selectivity plays a crucial role in catalytic systems where reactants and products exhibit comparable molecular dimensions,as it restricts the accessible configuration space of reaction intermediates.Herein,we designed a Cu@MFI catalyst by encapsulating Cu active sites within the well-defined micropores of MFI zeolite through a pore confinement strategy.This architecture preserves the zeolite framework integrity while maintaining unhindered internal mass transport,thereby enabling precise spatial control over transition-state configurations.Employing furfural hydrogenation as a probe reaction,the metal-zeolite synergy in Cu@MFI endowed the catalyst with exceptional activity(100%furfural conversion)and quantitative selectivity(100%furfuryl alcohol)at 70℃,sustained across a broad temperature window.Mechanistic studies reveal that the transition-state shape selectivity effectively prevented H2O interaction with the furan ring,offering valuable insights for other reaction systems seeking to exploit shape selectivity for specific transformations.
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.
基金supported by the Natural Science Foundation of Zhejiang Province(ZCLZ24B0301)the Lhasa Central Government Guiding Local Science and Technology Development Funds(No.LSKJ202458)the National Natural Science Foundation of China(No.22472150)。
文摘The electrocatalytic furfural oxidation reaction(FFOR)represents an economical and promising technology to replace conventional oxygen evolution reaction,enabling the co-production of high value chemicals and H_(2).Regulating the adsorption of furfural(FF)and OH^(-)species holds paramount importance in enhancing the overall performance.Herein,we have developed a unique CuO catalyst enriched with oxygen vacancies(O_(v)-CuO)resulting from the electrochemical reconstruction ofα-Cu_(2)S,which demonstrates exceptional FFOR performance,with a conversion of 95.3%,near-perfect selectivity and Faraday efficiency(FE)for furoic acid(FA)at 1.475 V vs.RHE.The study provides detailed comparison of the structural evolution of different sulfide precatalysts and their impact on FFOR.Furthermore,it delves into the structure-activity relationship through a combination of characterization and theoretical calculations.The O_(v)-CuO not only enhances OH^(-)adsorption,changes the rate-determining step,but also reduces the reaction energy barrier toward FFOR.Additionally,a much lower cell voltage is required to coproduce FA and hydrogen in the two-electrode co-electrolysis system.This work would provide valuable insights into the reaction mechanism of FFOR on Cu based catalysts and establish guidelines for designing defective electrocatalysts for biomass conversion.
基金supported by the National Natural Science Foundation of China (21273044, 21473035, 91545108)the Research Fund for the Doctoral Program of Higher Education (2012007000011)+2 种基金SINOPEC (X514005)Science & Technology Commission of Shanghai Municipality (08DZ2270500)the Open Project of State Key Laboratory of Chemical Engineering (SKL-ChE-15C02)~~
文摘The reductive transformation of furfural （FAL） into furfuryl alcohol （FOL） is an attractive route for the use of renewable bio‐sources but it suffers from the heavy use of H2. We describe here a highly efficient reduction protocol for converting aqueous FAL to FOL. A single phase rutile TiO2 support with a gold catalyst （Au/TiO2‐R） that used CO/H2O as the hydrogen source catalyze this reduction efficiently under mild conditions. By eliminating the consumption of fossil fuel‐derived H2, our pro‐cess has the benefit afforded by using CO as a convenient and cost competitive reducing reagent.
基金supported by the Ministry of Science and Technology of the People’s Republic of China, China (2018YFE0118100)the National Natural Science Foundation of China, China (21905275, 22025206, 21721004, 21991090)+5 种基金the Liaoning Revitalization Talents Program, China (XLYC2002012)the Joint Fund of the Yulin University and the Dalian National Laboratory for Clean Energy, China (Grant. YLU-DNL Fund 2021019)the CAS-NSTDA Joint Research Project, China (GJHZ2075)Dalian Institute of Chemical Physics, CAS, China (Grant: DICP I202131)the Science and Technology Commission of Shanghai Municipality, China (19DZ2271100)support of the Liaoning Key Laboratory of Biomass Conversion for Energy and Material。
文摘Photocatalytic hydrogenation of furfural offers an ideal method for selective biomass upgrading into value-added chemicals or fuel additives under mild conditions. However, it is still challenging to control the product selectivity due to side reactions of functional groups and reactive radical intermediates.Herein, photocatalytic transfer hydrogenation of furfural was studied using the TiO_(2)-based photocatalysts with alcohols as both the solvent and hydrogen donor. Ultralow loading metal supported on TiO_(2),together with adding a small amount of water in the system, were demonstrated to greatly increase the selectivity of furfuryl alcohol product. Electron paramagnetic resonance(EPR), ultraviolet-visible spectroscopy(UV-Vis) and photoluminescence(PL) measurements gave evidence that ultralow loading Pt or Pd on TiO_(2)increase the oxygen vacancy concentration and the photogenerated charge separation efficiency, which accelerates the photocatalytic reduction of furfural. In situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS) and mechanistic studies confirmed that photogenerated holes and electrons are active species, with dissociatively adsorbed methanol being directly oxidized by holes,furfural hydrogenated by protons and electrons and H_(2)O modifying the intermediate diffusion which contributes to high selectivity of furfuryl alcohol. This work demonstrates a simple approach to design photocatalysts and tune product selectivity in biomass valorization.
基金the National Basic Research Program of China，the National Natural Science Foundation of China，the Key Research Program of the Chinese Academy of Sciences，the Creative Foundation of President of Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences
基金supported by the National Natural Science Foundation of China(21233008,21643013,21690084)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB17020300)the Youth Innovation Promotion Association CAS(2013121)~~
文摘From both fundamental and practical perspectives, the production of chemicals from biomass re-sources using high-efficiency non-precious metal catalysts is important. However, many processes require addition of stoichiometric or excess quantities of base, which leads to high energy consump-tion, leaching problems, and side reactions. In this study, we investigated the high-efficiency oxida-tive esterification of furfural to methylfuroate by molecular oxygen with a Co-N-C/MgO catalyst. The catalyst was prepared by direct pyrolysis of a cobalt（Ⅱ） phenanthroline complex on MgO at 800℃ under N2 atmosphere. From furfural, 93.0% conversion and 98.5% selectivity toward methylfuroate were achieved under 0.5 MPa O2 with reaction at 100 ℃ for 12 h without a basic additive. The con-version and selectivity were much higher than those obtained with cobalt catalysts produced by pyrolysis of a cobalt（Ⅱ） phenanthroline complex on activated carbon or typical basic supports, in-cluding NaX, NaY, and CaO. X-ray photoelectron spectroscopy, X-ray diffraction, transmission elec-tron microscopy, and experimental results revealed that the high efficiency of Co-N-C/MgO for pro-duction of methylfuroate was closely related to the cobalt-nitrogen-doped carbon species and its catalytic ability in hydrogen abstraction. In contrast, Co-N-C（HCl） that synthesized by removing MgO with HCl from Co-N-C/MgO, as the catalyst produced mainly an acetal as a condensation prod-uct, and chloride ions had a negative effect on the oxidative esterification. Although the catalytic performance of the cobalt-nitrogen-doped carbon species was greatly affected by HCl treatment, it could be recovered to a great extent by addition of MgO. Moreover, changes in the oxygen pressure hardly affected the oxidative esterification of furfural with Co-N-C/MgO. This study not only pro-vides an effective approach to prepare methylfuroate, but also for designing high-performance non-precious metal catalysts for the oxidative esterification of biomass-derived compounds.
基金funded by United States National Science Foundation(NSF)Grant HRD-1036593USDA-NIFA Grant 12684238:Award No.2020-65209-31474United States Department of Energy Grant DE-SC0023345.
文摘Renewable resources based polymers provides a sustainable alternative to petroleum derived polymeric materials.As a part of our series on synthesis of vanillin based renewable polymers,we report the synthesis of poly(hydrovanilloin-furfural)[poly(HVL-Fur)]and poly(hydrovanilloin–5-hydromethylfurfural)[poly(HVL-5-HMF)].Vanillin was dimerized to a mixtures of meso/DL-hydrovanilloins with 94%meso product by electrochemical reductive coupling in aqueous sodium hydroxide using lead electrodes in quantitative yield.Then sodium hydroxide catalyzed condensation of hydrovanilloin with furfural in water at 80℃for 72 h was used to synthesize poly(HVL-Fur)with Mw=8600 g mol^(−1),PDI=1.28 in 78%yield.Similarly,condensation of hydrovanilloin with 5-hydroxymethylfurfural at 80℃for 48 h produced poly(HVL-5-HMF)with Mw=12,100 g mol−1,PDI=1.27 in 68%yield.poly(HVL-Fur)and poly(HVL-5-HMF)showed similar Tg values of 59℃and 60℃,respectively;whereas melting behaviors are dissimilar with Tm 171℃–173℃and 148℃–182℃,respectively.
基金financially supported by Youth Fund of National Natural Science Foundation of China(NO.22108175)National Natural Science Foundation of China(U190310)+3 种基金Natural Science Foundation of Liaoning province(2021-NLTS-12-09)Liaoning Innovation Talents Program in University(Liao[2020]389)Liaoning Revitalization Talents Program(XLYC1907029)Shenyang Young and Middle-aged Science&Technology Talents Program(RC210365).
文摘The gas-phase hydrogenation of furfural to furfuralcohol over Cr-free Cu-based catalysts has attracted increasing attention due to its environmentally friendly nature and mild operating conditions.Although reduced pure nano-sized CuO exhibits complete furfural hydrogenation and nearly 100%furfuralcohol selectivity,it suffers from rapid deactivation caused by sintering.In this study,we conducted comparative investigations on the catalytic performance and stability of two Cu-based catalysts:90%CuO-10%SiO_(2) and 90%CuO-5%CaO-5%SiO_(2),in the gas-phase furfural hydrogenation.The reaction is carried out under various conditions,including temperatures ranging from 120 to 170℃,LHSVs of 1 to 2.2 h^(-1),and H_(2) to furfural molar ratios of 3.5 to 12.5.The results indicate that under optimal conditions,the Ca-modified catalyst achieves nearly complete furfural conversion and almost 100%furfuralcohol selectivity for a test duration of 31 h.In contrast,the unmodified catalyst exhibits stable performance for only seven hours despite the similar initial performance.XRD analysis confirms that the gradual deactivation of both catalysts is attributed to the oxidation of reduced metallic Cu sites to Cu oxides.Further characterizations of the two spent catalysts using HRTEM and XPS analyses,along with DFT calculations,suggest that the presence of Ca in Cu lattices prevents the loss of electrons from low-valence Cu sites or the reduced metallic Cu sites,thus inhibiting their oxidation to high-valence Cu oxides.This phenomenon contributes to suppressing the deactivation of Cu-catalysts in the gas-phase furfural hydrogenation process.
基金supported by the National Hi-tech Research and Development Program of China(863 Program)(2012AA051801)the Fundamenta lResearch Funds for the Central Universities(No.CXZZ13 0112)
文摘A series of Cu-Mg-Al hydrotalcites derived oxides with a(Cu+Mg)/Al mole ratio of 3 and varied Cu/Mg mole ratio(from 0.07 to 0.30) were prepared by co-precipitation and calcination methods, then they were introduced to the hydrogenation of furfural in aqueous-phase. Effects of Cu/Mg mole ratio, reaction temperature, initial hydrogen pressure, reaction time and catalyst amount on the conversion rate of furfural as well as the selectivity toward desired product cyclopentanol were systematically investigated. The conversion of furfural over calcined hydrotalcite catalyst with a Cu/Mg mole ratio of 0.2 was up to 98.5% when the reaction was carried out under 140 ?C and the initial hydrogen pressure of 4 MPa for 10 h, while the selectivity toward cyclopentanol was up to 94.8%. The catalysts were characterized by XRD and SEM. XRD diffraction of all the samples showed characteristic pattern of hydrotalcite with varied peak intensity as a result of different Cu content. The catalytic activity was improved gradually with the increase of Cu component in the hydrotalcite.
基金financially supported by the National Natural Science Foundation of China (Nos. 20876176, 51172285, 51372277)the Natural Science Foundation of Shandong Province (ZR2011EL030)the Fundamental Research Funds for the Central Universities (14CX02060A)
文摘As an industrial byproduct of oil refining,furfural extract oil from reduced-pressure route Ⅱ with high aromatic content was used to prepare heat-resistant condensed polynuclear aromatic（COPNA） resin for the first time.The basic properties of furfural extract oil and the resultant COPNA resin were characterized by infrared spectroscopy（FT-IR）,nuclear magnetic resonance spectroscopy（1H-NMR）,thermogravimetric analysis（TGA） and elemental analysis（EA）.The result showed that heat treated furfural extract oil was successfully used for the synthesis of heat-resistant COPNA resin.The average structural parameters of raw materials and prepared resin were calculated by the improved Brown-Ladner method,and the averaged molecular structure of the resin was obtained.The reaction mechanism for the synthesis of COPNA resin was suggested as an acid-catalyzed positive ion type polymerization.
文摘Tandem catalysis for the hydrogenation rearrangement of furfural(FA)provides an attractive solution for manufacturing cyclopentanone(CPO)from renewable biomass resources.The Cu-Ni/Al-MCM-41 catalyst was synthesized and afforded excellent catalytic performance with 99.0%conversion and 97.7%selectivity to CPO in a near-neutral solution under 2.0 MPa H2 at 160℃ for 5 h,much higher than those on other molecular sieve supports including MCM-41,SBA-15,HY,and ZSM-5.A small amount of Al highly dispersed in MCM-41 plays an anchoring role and ensures the formation of highly dispersed CuNi bimetallic nanoparticles(NPs).The remarkably improved catalytic performance may be attributed to the bimetallic synergistic and charge transfer effects.In addition,the initial FA concentration and the aqueous system pH required precise control to minimize polymerization and achieve high selectivity of CPO.Fourier transform infrared spectroscopy and mass spectra results indicated that polymerization was sensitive to pH values.Under acidic conditions,FA and intermediate furfuryl alcohol polymerize,while the intermediate 4-hydroxy-2-cyclopentenone mainly polymerizes under alkaline conditions,blocking the cascade of multiple reactions.Therefore,near-neutral conditions are most suitable for minimizing the impact of polymerization.This study provides a useful solution for the current universal problems of polymerization side reactions and low carbon balance for biomass conversion.
基金supported by the National Natural Science Foundation of China(21573031 and 21428301)the Fundamental Research Funds for the Central Universities(DUT15ZD106)
文摘Spinel ferrites NiFeOsupported Ru catalysts have been prepared via a simple sol–gel route and applied for converting biomass-derived furfural to 2-methylfuran. The as-prepared catalysts were characterized by thermogravimetric analysis（TG）, Nadsorption–desorption, X-ray diffraction（XRD）, scanning electronic microscopy（SEM）, and X-ray photoelectron spectroscopy（XPS）. Results showed that the catalysts had well-dispersed Ru active sites and large surface area for calcination temperature ranging from 300 to 500 ℃. The conversion of biomass-derived furfural into 2-methylfuran was conducted over Ru/NiFeOthrough catalytic transfer hydrogenation in liquid-phase with 2-propanol as the hydrogen source. A significantly enhanced activity and increased 2-methylfuran yield have been achieved in this study. Under mild conditions（180 ℃ and 2.1 MPa N）, the conversion of furfural exceeds 97% and 2-methylfuran yield was up to 83% over the catalyst containing 8 wt% Ru. After five repeated uses, the catalytic activity and the corresponding product yield remained almost unchanged. The excellent catalytic activity and recycling performance provide a broad prospects for various practical applications.
文摘To solve soil shortage in reclaiming subsided land of coal mines, the principal chemical properties of artificial soil formed by mixing organic furfural residue and inorganic fly ash were examined. The results indicated that the artificial soil was suitable for agriculture use after irrigation and desalination, the available nutrients in the artificial soil could satisfy the growth demand of plants, and the pH tended to the neutrality.
基金supported by the Natural Science Foundation of China (No.21106143)100-talent project of Dalian Institute of Chemical Physics (DICP)the Independent Innovation Foundation of State Key Laboratory of Catalysis (No.R201113)
文摘Phosphoric acid treated niobic acid(NbP)was used for the dehydration of xylose to furfural in biphasic solvent system,which was found to exhibit the best performance among the tested catalysts.The excellent performance of NbP could be explained by the better synergistic cooperation between Bro¨nsted and Lewis acid sites.Moreover,NbP showed good stability and no obvious deactivation or leaching of Nb could be observed after six continuous recycles.
基金the Major National Science & Technology Projects of China on Water Pollution Control and Treatment (No. 2012ZX07501002-001)for the financial support
文摘An environmentally benign processing approach for furfural production from xylose and xylan under very mild conditions（353–373 K） was developed with the addition of metal chlorides in ChCl–oxalic acid（a deep eutectic solvent（DES）） synthesized from cheap and renewable starting materials）. ChCl–oxalic acid acted as both a Br？nsted acid catalyst and a reaction medium in this catalytic route. In addition, a biphasic system with methyl isobutyl ketone as an extracting reagent（DES/MIBK） to further increase furfural yield was also proposed. This processing approach for producing furfural eliminated the large energy consumption for high pressure saturated steam and the generation of acidic effluent, which was very difficult to handle. The whole catalytic system was more environmentally friendly compared with the commercial process for furfural production.
基金Project supported by the National Key Technology Research and Development Program of China(No.2006BAD07A01,2006BAD10B05-02).
文摘Furfural is an important inhibitor in ethanol fermentation process using lignocellulosic hydrolysates as raw materials. In order to find out the furfural concentration range in which furfural inhibits the fermentation process, we used one strain Saccharomyces kluyveri selected from soil and cultured in several different furfural content media under low glucose concentration condition. Experiment results showed that microorganism growth was stimulated and dry cell weight decreased when furfural concentration in the medium was 0.25 mg/ml. Furfural had negative effect on cell growth when its concentration was above 1.00 mg/ml. At the same time, the strain growed better and had a higher glucose consumption rate in 5% original glucose concentration condition than in 3% original glucose concentration condition. The results showed that appropriate exaltation of original glucose concentration in stalk hydrolysates will increase the strain resistance to furfural.
