Lignin contains abundant aromatic ring structures,which can be converted into green sustainable aviation fuelrange arenes through hydrodeoxygenation(HDO).A series of supported FeMoS/NC catalysts were synthesized by a ...Lignin contains abundant aromatic ring structures,which can be converted into green sustainable aviation fuelrange arenes through hydrodeoxygenation(HDO).A series of supported FeMoS/NC catalysts were synthesized by a hydrothermal method.The HDO performance of the catalysts was evaluated using 4-ethylguaiacol as a model compound at 340℃ under 3 MPa H2.The MoS_(2)/NC catalyst exhibited a deoxygenation degree of 83.4%,whereas the Fe-modified catalyst(Fe_(0.3)MoS/NC)attained complete deoxygenation(100%)with an arenes selectivity of 78.6%.Beyond the optimal ratio,the deoxygenation degree is inversely proportional to the Fe/Mo molar ratio.The catalysts were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),low-temperature nitrogen adsorption(BET method)and X-ray photoelectron spectroscopy(XPS).The characterization results indicated that the introduction of Fe enhanced the uniform dispersion of MoS_(2)on the NC support surface.This modification further increased the acidity of the catalyst surface and raised the concentration of sulfur vacancies,thereby promoting the adsorption of oxygencontaining compounds.Furthermore,the HDO performance of the Fe_(0.3)MoS/NC catalyst was evaluated using actual lignin as a feedstock under the conditions of 340℃,3 MPa H2 and 12 h.The results showed a green hydrocarbon yield of 65.5%,of which the C_(8)-C_(16)fraction accounted for 54.4%of the total hydrocarbons.Within this fraction,aromatic compounds constituted 63.4%,suggesting its potential use as green aviation fuel-range arenes.This work thus establishes a viable catalytic pathway for efficient conversion of lignin to arenes.展开更多
The aim of this research was to synthesize a new totally bio wood adhesive entailing the use of oxidized starch(OST),urea,and oxidized lignin(OL).For this reason,non-modified(L)and oxidized lignin(OL)at different cont...The aim of this research was to synthesize a new totally bio wood adhesive entailing the use of oxidized starch(OST),urea,and oxidized lignin(OL).For this reason,non-modified(L)and oxidized lignin(OL)at different contents(20%,30%,and 40%)were used to prepare the starch-urea-lignin(SUL)and starch-urea-oxidized lignin(SUOL)resin.Sodium persulfate(SPS)as oxidizer was employed to oxidize both starch and lignin.Urea was just used as a low cost and effective crosslinker in the resin composition.The properties of the synthesized resins and the plywood panels bonded with themweremeasured according to relevant standards.The viscosity and gel time of the SUOL resins containing oxidized lignin are respectively higher and faster than for non-modified lignin(SUL).The lignin phenolic hydroxyl groups(-OH)proportion was markedly increased by oxidation as shown by Fourier Transform Infrared(FTIR)spectrometry.The molecular mass and the polydispersity of the lignin did also decrease by its oxidization pretreatment.DSC analysis showed a decrease of the glass transition temperature of the lignin(Tg)due to its oxidation.The thermal analysis of the oxidized lignin SUOL resin also showed that it had a lower peak temperature than the SUL equivalent non-modified lignin resin.The plywood panels bonded with oxidized lignin gave acceptable bending modulus,bending strength,peak temperature by thermal analysis and dry shear strength as well as a better plywood dimensional stability when used in the SUOL formulation.The synthesized SUOL adhesive is a lignin-derived,totally bio,no-aldehyde added,inexpensive resin applicable to bond plywood.展开更多
Lignin,the most abundant natural aromatic polymer globally,has garnered considerable interest due to its rich and diverse active functional groups and its antioxidant,antimicrobial,and adhesive properties.Recent resea...Lignin,the most abundant natural aromatic polymer globally,has garnered considerable interest due to its rich and diverse active functional groups and its antioxidant,antimicrobial,and adhesive properties.Recent research has significantly improved the performance of lignin-based hydrogels,suggesting their substantial potential in fields such as biomedicine,environmental science,and agriculture.This paper reviews the process of lignin extraction,systematically introduces synthesis strategies for preparing lignin-based hydrogels,and discusses the current state of research on these hydrogels in biomedical and environmental protection fields.It concludes by identifying the existing challenges in lignin hydrogel research and envisioning future prospects and development trends.展开更多
Lignin is a significant secondary metabolite produced through the phenylpropanoid pathway.As a vital component of the plant cell wall,lignin affects various fruit characteristics,including size,seed quantity,and firmn...Lignin is a significant secondary metabolite produced through the phenylpropanoid pathway.As a vital component of the plant cell wall,lignin affects various fruit characteristics,including size,seed quantity,and firmness.In this study,we conducted comprehensive identification and phylogenetic analysis of 265 Caffeic acid O-methyltransferase(COMT)genes across ten different plant species,including Vaccinium corymbosum and four other Vaccinium species.The results reveal that VcCOMT38 is a promising structural gene for the biosynthesis of lignin in blueberry.An in vitro enzymatic assay of VcCOMT38 demonstrated that it is a special enzyme in the lignin biosynthesis pathway and prefers to use caffeic acid as a substrate over 5-hydroxyferulic acid.Transient overexpression and silencing of VcCOMT38 in Vaccinium corymbosum‘Northland’fruits demonstrated that VcCOMT38 participates in lignin biosynthesis and contributes to both an increased number of immature seeds and enhanced fruit firmness.The heterologous overexpression of VcCOMT38 in Nicotiana benthamiana revealed that this gene could increase the lignin content and the syringyl/guaiacyl(S/G)ratio,which determines the maximum monomer yield during lignin depolymerization.These results highlight VcCOMT38 as a crucial gene in lignin biosynthesis and its potential for improving lignin production in industry through genetically modified woody plants.展开更多
Near-infrared(NIR)light-responsive shape memory polymers(SMPs)show great promise for biomedical applications,but conventional photothermal agents suffer from high cost,complex preparation,or poor biocompatibility,whil...Near-infrared(NIR)light-responsive shape memory polymers(SMPs)show great promise for biomedical applications,but conventional photothermal agents suffer from high cost,complex preparation,or poor biocompatibility,while lignin-based alternatives exhibit insufficient photothermal conversion efficiency.Herein,we developed a novel strategy to enhance photothermal performance of lignin through sequential demethylation modification and Fe^(3+)complexation for constructing NIR light responsive SMPs.Dealkaline lignin(DL)was first demethylated using iodocyclohexane to produce demethylated lignin(DDL)with increased catechol content,which was then incorporated into polycaprolactone-based polyurethane synthesis followed by Fe^(3+)complexation.Results showed that DDL-Fe^(3+)complexes have significantly enhanced photothermal conversion performance,and the resulting PU-DDL+Fe^(3+)polyurethane with 0.5 wt%DDL content demonstrated a temperature increases of 39.8℃under 0.33 W·cm-2808 nm NIR irradiation.This excellent photothermal performance enables the shape-fixed PU-DDL+Fe^(3+)polyurethane to rapidly recover to its initial shape under NIR light irradiation.Additionally,PU-DDL+Fe^(3+)polyurethane exhibits good mechanical properties and biocompatibility,demonstrating significant biomedical application potential.展开更多
Developing on-demand biomass valorization represents an ideal path to alleviate the double burden of a sustainable energy-environment future,yet exploring tunable lignin-first chemistry to accomplish multifunctional w...Developing on-demand biomass valorization represents an ideal path to alleviate the double burden of a sustainable energy-environment future,yet exploring tunable lignin-first chemistry to accomplish multifunctional water purification remains elusive.Herein,we report a versatile solvent-fractionation to construct heteroatom-doped multicolor lignin carbon quantum dots(CQDs)with the functions of bimodal pollutant sensing,metal-ionic visualization,and photocatalytic antibiotic dissociation.With the aid of oxidation cleavage and biphasic extraction,the underlying lignin features of molecular weight and functional linkages influence the quantum size and core-surface state of CQDs conferring the unique optical-structure-performance.The N,S co-doped blue-emitting CQDs via light-quenching offer the selective identification of Fe^(3+)-ions in a broad response range with an acceptable limit of detection.The addition of L-cysteine can efficiently restore the fluorescence of CQDs by forming a stable Fe^(3+)-L-cys complex.The green-emissive CQDs are facilely embedded into cellulose hydrogel to directly visualize the presence of metal-ions.A red-CQDs modified ternary ZnIn2S4(ZIS)composite is fabricated to achieve photocatalytic antibiotic removal with an efficiency of~85%.The excellent photo-generated electron and storage capabilities of CQDs improve the light-capturing,electron conduction,and charge carrier separation of ZIS.The reactive species are of importance to photocatalytic tetracycline oxidation,wherein the electron holes(h+)function as the main contributor followed by∙O_(2)^(-),1O2 and∙OH.The directly interfacial electron escaping-shuttling with the help of optimized electronic and energy-band structures is confirmed via electrochemical test and theoretical computation.We anticipate that the present work not only sheds substantial light to manipulate polychromatic lignin-based CQDs via a tailored solvent-engineering,but also presents an emerging green route of emphasizing biomass-water nexus.展开更多
Lodging is a major constraint limiting oil flax production efficiency in northern China.Crop lodging susceptibility is closely related to stem lignin content,and the regulatory mechanisms by which nitrogen and potassi...Lodging is a major constraint limiting oil flax production efficiency in northern China.Crop lodging susceptibility is closely related to stem lignin content,and the regulatory mechanisms by which nitrogen and potassium fertilization interactively influence lignin biosynthesis in oil flax stems require further investigation.Therefore,this study aimed to enhance lodging resistance and increase grain yield in oil flax.We examined the interactive effects of different nitrogen (75,150,and 225 kg N ha^(–1)) and potassium (60 and 90 kg K_(2)O ha^(–1)) fertilizer rates on lignin metabolism,lodging resistance,and grain yield during the 2022 and 2023 growing seasons.Results indicated that nitrogen and potassium fertilizer levels and their interactions promoted lignin accumulation,improved lodging resistance,and increased grain yield.Compared to the control (CK),the75–150 kg N ha^(–1) combined with 60 kg K_(2)O ha^(–1) treatments significantly enhanced the activities of key lignin-synthesizing enzymes (tyrosine ammonia-lyase (TAL),phenylalanine ammonia-lyase (PAL),cinnamyl alcohol dehydrogenase (CAD),and peroxidase (POD)) and upregulated the expression of 4CL1 and F5H3 genes,leading to a 29.63–43.30%increase in lignin content,improved stem bending strength and lodging resistance index,and a 23.27–32.34%increase in grain yield.Correlation analysis revealed that nitrogen and potassium fertilizers positively regulated enzyme activities and gene expression related to lignin biosynthesis,thereby facilitating lignin accumulation and enhancing stem mechanical strength and lodging resistance.Positive correlations were observed among lignin-related enzyme activities,gene expression,lodging resistance traits,and grain yield.In summary,the application of 75–150 kg N ha^(–1) in conjunction with 60 kg K_(2)O ha^(–1)promoted lignin biosynthesis and accumulation,enhanced lodging resistance,and increased grain yield in oil flax grown in the dryland farming region of central Gansu,China.Furthermore,this treatment provides a technical basis for cultivating stress-tolerant and high-yield oil flax in arid regions.展开更多
Research-based on lignin as a bioproduct has grown due to its high availability,reactivity,physicochemical sta-bility,and abundance of different aromatic units.Lignin consists of various functional groups,which can re...Research-based on lignin as a bioproduct has grown due to its high availability,reactivity,physicochemical sta-bility,and abundance of different aromatic units.Lignin consists of various functional groups,which can react in various chemical reactions and serve as a raw material in various processes to obtain multiple products.These characteristics make lignin suitable for synthesizing products from natural raw materials,replacing fossil ones.Due to a high aromatic variety and complex structural arrangement,lignin isolation and fractionation are still challenging.The aim and novelty of this work was the modification of severity and enzymatic hydrolysis proce-dure on an industrial pre-treatment to improve by-products of birch processing as a raw material for the potential production of different products.Lignin from birch wood enzymatic hydrolysis was obtained and marked accord-ingly:HS(high severity),MS(medium severity),and LS(low severity)lignin.Samples were characterized by ash content,analytical pyrolysis,solubility,and viscosity.HS lignin was characterized by a relatively high carbohy-drate content(16%)and lower lignin content(77%).Meanwhile,LS lignin showed increased lignin content(83%)and reduced carbohydrate content(9%).It can be concluded that the delignification process greatly influ-ences the properties of the obtained lignin.HS lignin resulted in a lower polydispersity index(PDI)and more condensed structure,while LS lignin showed a higher PDI but a lower content of carbohydrates.Therefore,look-ing for a golden middle way is necessary whilefinding the conditions according to the usefield.展开更多
The growing environmental awareness,the search for alternatives to fossil resources,and the goal of achieving a circular economy have all contributed to the increasing valorization of biowaste to produce bio-based pol...The growing environmental awareness,the search for alternatives to fossil resources,and the goal of achieving a circular economy have all contributed to the increasing valorization of biowaste to produce bio-based polymers and other high-value products.Among the various biowaste materials,lignin has gained significant attention due to its high aromatic carbon content,low cost,and abundance.Lignin is predominantly sourced as a byproduct from the paper industry,available in large quantities from hardwood and softwood,with variations in chemical structure and susceptibility to hydrolysis.This study focuses on softwood lignin obtained through the LignoForce^(TM) technology,comparing the thermal and chemical characteristics,and stability,of a recently produced batch with that of a batch that has been stored for four years.Additionally,the development of lignin-based thermoplastic polymer mixtures using Polyethylene Terephthalate Glycol(PET-G)and a blend of Polycarbonate and Acrylonitrile-Butadiene-Styrene(PC/ABS)with high lignin content(50–60 wt%)is explored,as well as the production of filaments for carbon fiber production.For this purpose,following melt mixing,the lignin-based mixtures were spun into filaments,which were subsequently subjected to thermal stabilization in an oxidative atmosphere.The lignin phase was well distributed in the PET-Gmatrix and the twomaterials presented a good interface,which further improved after thermal treatment under an oxidative atmosphere.After thermal treatment an increase in tensile modulus,tensile strength,and elongation at break of approximately 160%,200%,and 100%,respectively,was observed,confirming the good interface established,and consistent with structural changes such as cross-linking.Conversely,the PC/ABS blend did not form a good interface with the lignin domains after melt mixing.Although the interactions improved after thermal treatment,the tensile strength and elongation at break decreased by approximately 30%,while themodulus increased by approximately 20%.Overall,the good processability of the lignin/polymer mixtures into filaments,and their physical,chemical,and mechanical characterization before and after thermal oxidation are good indicators of the potential as precursors for carbon fiber production.展开更多
With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin...With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable supercapacitors.By depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene lamella.Moreover,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of lignin.All these strategies effectively enhanced the capacitive performance of the electrodes.In addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the electrodes.Flexible electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),respectively.Moreover,their capacitances were well preserved after 1000 times of 600%stretch-release cycling.This study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.展开更多
The emission of organic pollutants from the dye industry and medical treatment represents a significant threat to the quality of water resources and human health.The development of green,environmentally friendly and e...The emission of organic pollutants from the dye industry and medical treatment represents a significant threat to the quality of water resources and human health.The development of green,environmentally friendly and efficient photocatalysts for the removal of organic pollutants from the environment is of paramount importance in addressing these issues.Flower-like lignin-derived carbon(LC)/zinc oxide(ZnO)composites with controllable morphology were synthesized via a direct precipitation method.In this study,alkali lignin was employed as an anionic active agent to alter the molecular arrangement on the liquid surface during the synthesis reaction and to reduce the surface tension between mixtures,thereby forming a special stacked morphology,which was then used for the highly efficient removal of methylidene blue(MB)and tetracycline hydrochloride(TCH)in water under different light conditions.The formation mechanism of LC/ZnO and the degradation characteristics under different reaction conditions were investigated.The loading of LC can form composites with large specific surface area and rich porous structure.In addition,with the help of lignin,the morphology of ZnO was changed from a rod-like structure to a lamellar structure,and LC could effectively reduce the band gap of ZnO,which could improve the electron transfer rate in the photocatalytic process.The·O_(2)^(-)and·OH radicals generated under photoexcitation promoted the decomposition of pollutants.This study presents a simple,economical,and scalable method for the application of photocatalysts and explores new ways for the high-value application of industrial lignin.展开更多
Carbon fibers(CFs)with notable comprehensive properties,such as light weight,high specific strength,and stiffness,have garnered considerable interest in both academic and industrial fields due to their diverse and adv...Carbon fibers(CFs)with notable comprehensive properties,such as light weight,high specific strength,and stiffness,have garnered considerable interest in both academic and industrial fields due to their diverse and advanced applications.However,the commonly utilized precursors,such as polyacrylonitrile and pitch,exhibit a lack of environmental sustainability,and their costs are heavily reliant on fluctuating petroleum prices.To meet the substantial market demand for CFs,significant efforts have been made to develop cost-effective and sustainable CFs derived from biomass.Lignin,the most abundant polyphenolic compound in nature,is emerging as a promising precursor which is well-suited for the production of CFs due to its renewable nature,low cost,high carbon content,and aromatic structures.Nevertheless,the majority of lignin raw materials are currently derived from pulping and biorefining industrial by-products,which are diverse and heterogeneous in nature,restricting the industrialization of lignin-derived CFs.This review classifies fossil-derived and biomass-derived CFs,starting from the sources and chemical structures of raw lignin,and outlines the preparation methods linked to the performance of lignin-derived CFs.A comprehensive discussion is presented on the relationship between the structural characteristics of lignin,spinning preparation,and structure-morphology-property of ligninderived CFs.Additionally,the potential applications of these materials in various domains,including energy,catalysis,composites,and other advanced products,are also described with the objective of spotlighting the unique merits of lignin.Finally,the current challenges faced and future prospects for the advancement of lignin-derived CFs are proposed.展开更多
Electrochemical conversion of lignin for the production of high-value heterocyclic aromatic compounds has great potential.We demonstrate the targeted synthesis and cation modulation of NiCo_(2)O_(4)spinel nanoboxes,sy...Electrochemical conversion of lignin for the production of high-value heterocyclic aromatic compounds has great potential.We demonstrate the targeted synthesis and cation modulation of NiCo_(2)O_(4)spinel nanoboxes,synthesized via cation exchange and calcination oxidation.These catalysts exhibit excellent efficacy in the electrocatalytic conversion of lignin model compounds,specifically 2-phenoxy-1-phenylethanol,into nitrogen-containing aromatics,achieving high conversion rates and selectivities.These catalysts were synthesized via a cation exchange and calcination oxidation process,using Prussian blue nanocubes as precursors.The porous architecture and polymetallic composition of the NiCo_(2)O_(4)spinel demonstrated superior performance in electrocatalytic oxidative coupling,achieving a 99.2 wt%conversion rate of the 2-phenoxy-1-phenylethanol with selectivities of 37.5 wt%for quinoline derivatives and 31.5 wt%for phenol.Key innovations include the development of a sustainable one-pot synthesis method for quinoline derivatives,the elucidation of a multistage reaction pathway involving CAO bond cleavage,hydroxyaldol condensation,and CAN bond formation,and a deeper mechanistic understanding derived from DFT simulations.This work establishes a new strategy for lignin valorization,offering a sustainable route to produce high-value nitrogen-containing aromatics from renewable biomass under mild conditions,without the need for additional reagents.展开更多
Ni-based catalysts are widely applied in the hydrodeoxygenation of lignin derivatives via C-O cleavage for the production of cycloalkanes.However,they often have difficulty in achieving high activity under mild condit...Ni-based catalysts are widely applied in the hydrodeoxygenation of lignin derivatives via C-O cleavage for the production of cycloalkanes.However,they often have difficulty in achieving high activity under mild conditions and exhibit relatively poor stability,and rare studies focus on the cleavage of the stubborn interunit C-C linkages.To address this issue,we developed a Ni@AlPO_(4)/Al_(2)O_(3)catalyst in which the surface of Ni nanoparticles was decorated by AlPO_(4)species,demonstrating excellent catalytic activity and stability in the C-C and C-O cleavages.In the hydrodeoxygenation of guaiacol,this catalyst afforded99.1%conversion and 92.9%yield of cyclohexane under 1 MPa H_(2)at 230℃ for 2 h.More important,this catalyst maintained unchanged performance even after 6 runs with the conversion controlled at about50%,Mecha nistic investigations revealed that the moderate surface coverage of AlPO_(4)on Ni with the formation of Ni^(δ+)-AlPO_(4)interface significantly facilitated the conversion of methoxycyclohexanol and cyclohexanol to cyclohexane,whereas,excess coverage would also block the access to Ni site.Moreover,Ni@AlPO_(4)/Al_(2)O_(3)demonstrated broad applicability in the C-O cleavage of various typical lignin monomers and dimers into cycloalkanes.To our delight,this catalyst also displayed pretty good activity even in the simultaneous cleavage of C-C linkages and C-O bonds for the lignin-derived C-C dimers,achieving cycloalkanes as final products.As a consequence,a 27.1 wt%yield of monocycloalkanes was obtained in the depolymerization of poplar lignin with both C-C and C-O cleavages.展开更多
Many strategies have been proposed to produce arenes from lignin as liquid fuel additives.However,the development of these methods is limited by the low yield of products,low atom utilization,and inefficient lignin de...Many strategies have been proposed to produce arenes from lignin as liquid fuel additives.However,the development of these methods is limited by the low yield of products,low atom utilization,and inefficient lignin depolymerization.Herein,we develop an energy-efficient synthetic method for the production of high-carbon-number arenes from sustainable lignin with a total yield of 23.1 wt%.Particularly,high carbon number arenes are obtained by fully utilizing the formaldehyde stabilizing additive and the methoxy group in lignin.The process begins with the reductive depolymerization of formaldehyde-stabilized lignin,followed by transmethylation between lignin monomers over Au/Nb_(2)O_(5) catalyst,and the Ru/Nb2O5-catalyzed hydrodeoxygenation.This work demonstrates the potential of value-added arenes production directly from lignin.展开更多
Carbon quantum dots are a new type of fluorescent nanomaterials with broad applications in drug delivery,bioimaging,solar cells,and photocatalysis due to their unique biocompatibility,optical properties and easy funct...Carbon quantum dots are a new type of fluorescent nanomaterials with broad applications in drug delivery,bioimaging,solar cells,and photocatalysis due to their unique biocompatibility,optical properties and easy functionalization.In the meantime,because of its high carbon content,renewable nature,and environmental friendliness,lignin has drawn the attention of researchers as a desirable raw material for creating carbon quantum dots.Here we review the synthesis of carbon quantum dots from lignin,focusing on synthetic methods,properties,and applications in energy,and photocatalysis.Later,we propose some new development prospects from preparation methods,luminescence mechanism research,application,and commercial cost of lignin carbon quantum dots.Finally,based on this,the development prospects of this field are prospected and summarized.展开更多
Lignin has been proved to be a promising precursor for producing carbon foam.The thermal and chemistry properties of lignin during its thermal conversion make it quite unique comparing with other precursors,and the co...Lignin has been proved to be a promising precursor for producing carbon foam.The thermal and chemistry properties of lignin during its thermal conversion make it quite unique comparing with other precursors,and the conversion parameters can clearly affect the properties of the derived products.Therefore,this study systematically investigated the effects of key carbonization parameters on the properties of the resulting carbon foam materials.The findings demonstrate that the performance of the self-shaping lignin-derived carbon foam is simultaneously influenced by the factors that carbonization temperature,heating rate,and carbonization duration.Specifically,the carbonization temperature and carbonization duration have a significant impact on the mechanical performance,where higher temperatures and long carbonization time improve compressive strength and specific strength.Moreover,the data revealed that elevated temperatures,rapid heating rates,and shortened carbonization periods collectively promoted the development of higher porosities and larger pore diameters within the carbon foam structure.Conversely,lower carbonization temperatures,slower heating rates,and extended carbonization durations facilitated the formation of microporous in the carbon foam.This study provides a scientific foundation for optimizing the production of lignin-derived carbon foam with tailored properties and performance characteristics.展开更多
As the most abundant aromatic bio-based polymer,lignin has great potential as a sustainable feedstock for building crosslinked thermoset polymers as bio-based adhesives.However,the potential of hardwood kraft lignin(H...As the most abundant aromatic bio-based polymer,lignin has great potential as a sustainable feedstock for building crosslinked thermoset polymers as bio-based adhesives.However,the potential of hardwood kraft lignin(HKL)is limited due to its poor crosslinking reactivity.Hence,for the first time,the present study reports the facile oxidation of HKL involving a redox reaction with silver-ammonia complexes([(AgNH3)2]+),primarily focusing on oxidation to produce reactive quinones and promote C-C linkages during reaction.This study aims to increases reactivity of oxidized HKL for effective crosslinking with monoethanolamine(MEA)for the development of bio-based wood adhesives.The characterization,including 13C-nuclear magnetic resonance(NMR)and Fourier transform infrared(FT-IR)spectroscopy,confirms the oxidation reaction,such as the formation of quinones(C=O)and subsequent crosslinking between the oxidized HKL molecules and MEA.Additionally,gel permeation chromatography(GPC)confirms the C-C and C-O linkages with increased molecular weight after oxidation,and is supported by differential scanning calorimetry(DSC)which shows the exothermic reaction due to the crosslinking of the oxidized HKL molecules via condensation to form C-C and C-O linkages.The crosslinked HKL/MEA-based adhesives underwent mild reaction and achieved a maximum dry shear strength of 0.77 MPa,which exceeds the standard requirement of 0.6 MPa.These findings demonstrate not only a one-pot oxidation for improving the reactivity of HKL using silver complexes,but also its facile crosslinking with MEA for sustainable bio-based wood adhesives.展开更多
Oxidative catalysis enables lignin depolymerization to yield carbonyl-containing aromatic chemicals for sustainable lignocellulose valorization.The oxidative depolymerization of lignin requires high oxygen pressure an...Oxidative catalysis enables lignin depolymerization to yield carbonyl-containing aromatic chemicals for sustainable lignocellulose valorization.The oxidative depolymerization of lignin requires high oxygen pressure and harsh conditions to trade off lignin’s structural complexity and limited solubility.Herein,we developed an oxidation system for lignin depolymerization using a single phosphomolybdic acid(H_(3)PMo_(12)O_(40))catalyst in acetic acid solvent to address the aforementioned issues.The entire catalytic system was operated under only 0.1 MPa O_(2) pressure,providing over 20 wt% of aromatic compounds containing aldehydes and carboxylic acids.Theoretical calculations combined with experimental analyses reveal structural transformations and redox behavior driven by the synergistic interaction between H_(3)PMo_(12)O_(40) and acetic acid.Mechanistic studies detected superoxide radicals,confirming the joint role of catalyst and solvent in oxygen activation,radicals stabilization,and enhanced reaction efficiency.A low-cost,commercially available catalyst with minimal oxygen demand offers a promising route to industrial-scale biomass refining.展开更多
Developing favorable bio-based polymers that replace petroleum-based plastics is an essential environmental demand.Lignin is a by-product of the chemical pulping industry.It is a natural UV protection ingredient in br...Developing favorable bio-based polymers that replace petroleum-based plastics is an essential environmental demand.Lignin is a by-product of the chemical pulping industry.It is a natural UV protection ingredient in broad-spectrum(UVA and UVB)sunscreens.It could be partially and selectively acetylated in a simple,fast,and more reliable process.In this work,a composite film was prepared with UV-resistant properties through a casting method.Bio-based cellulose acetate(CA)was employed as a major matrix while nano-acetylated kraft lignin(AL-NPs)was used as filler during synthesizing UV-shielding films loaded with various amounts(1–5 wt.%)of AL-NPs.Kraft lignin was acetylated through a simple and fast microwave-assisted process using acetic acid as a solvent and acetylating agent.The physicochemical and morphological characteristics of the prepared films were evaluated using different methods,including scanning electron microscopy(SEM),Fourier Transform Infrared Spectroscopy(FTIR),X-ray diffraction analysis(XRD),mechanical testing and contact angle measurement.The UV-Vis spectroscopy optical investigation of the prepared films revealed that AL-NPs in the CA matrix showed strong UV absorption.This feature demonstrated the effectiveness of our research in developing UV-resistant bio-based polymer films.Hence,the prepared films can be considered as successful candidates to be applied in packaging applications.展开更多
基金Supported by grants from National Key Research and Development Program of China(2024YFB4205903)the National Natural Science Foundation of China(52274308,U22B20144,22278440 and 22078362)Shandong Provincial Technology Innovation Guidance Plan(YDZX2023060)。
文摘Lignin contains abundant aromatic ring structures,which can be converted into green sustainable aviation fuelrange arenes through hydrodeoxygenation(HDO).A series of supported FeMoS/NC catalysts were synthesized by a hydrothermal method.The HDO performance of the catalysts was evaluated using 4-ethylguaiacol as a model compound at 340℃ under 3 MPa H2.The MoS_(2)/NC catalyst exhibited a deoxygenation degree of 83.4%,whereas the Fe-modified catalyst(Fe_(0.3)MoS/NC)attained complete deoxygenation(100%)with an arenes selectivity of 78.6%.Beyond the optimal ratio,the deoxygenation degree is inversely proportional to the Fe/Mo molar ratio.The catalysts were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),low-temperature nitrogen adsorption(BET method)and X-ray photoelectron spectroscopy(XPS).The characterization results indicated that the introduction of Fe enhanced the uniform dispersion of MoS_(2)on the NC support surface.This modification further increased the acidity of the catalyst surface and raised the concentration of sulfur vacancies,thereby promoting the adsorption of oxygencontaining compounds.Furthermore,the HDO performance of the Fe_(0.3)MoS/NC catalyst was evaluated using actual lignin as a feedstock under the conditions of 340℃,3 MPa H2 and 12 h.The results showed a green hydrocarbon yield of 65.5%,of which the C_(8)-C_(16)fraction accounted for 54.4%of the total hydrocarbons.Within this fraction,aromatic compounds constituted 63.4%,suggesting its potential use as green aviation fuel-range arenes.This work thus establishes a viable catalytic pathway for efficient conversion of lignin to arenes.
基金funded by Semnan University,research grant No.226/1403/T140211.
文摘The aim of this research was to synthesize a new totally bio wood adhesive entailing the use of oxidized starch(OST),urea,and oxidized lignin(OL).For this reason,non-modified(L)and oxidized lignin(OL)at different contents(20%,30%,and 40%)were used to prepare the starch-urea-lignin(SUL)and starch-urea-oxidized lignin(SUOL)resin.Sodium persulfate(SPS)as oxidizer was employed to oxidize both starch and lignin.Urea was just used as a low cost and effective crosslinker in the resin composition.The properties of the synthesized resins and the plywood panels bonded with themweremeasured according to relevant standards.The viscosity and gel time of the SUOL resins containing oxidized lignin are respectively higher and faster than for non-modified lignin(SUL).The lignin phenolic hydroxyl groups(-OH)proportion was markedly increased by oxidation as shown by Fourier Transform Infrared(FTIR)spectrometry.The molecular mass and the polydispersity of the lignin did also decrease by its oxidization pretreatment.DSC analysis showed a decrease of the glass transition temperature of the lignin(Tg)due to its oxidation.The thermal analysis of the oxidized lignin SUOL resin also showed that it had a lower peak temperature than the SUL equivalent non-modified lignin resin.The plywood panels bonded with oxidized lignin gave acceptable bending modulus,bending strength,peak temperature by thermal analysis and dry shear strength as well as a better plywood dimensional stability when used in the SUOL formulation.The synthesized SUOL adhesive is a lignin-derived,totally bio,no-aldehyde added,inexpensive resin applicable to bond plywood.
基金supported by the National Natural Science Foundation of China(21706052,22278114)Natural Science Foundation of Henan Province(242300421575).
文摘Lignin,the most abundant natural aromatic polymer globally,has garnered considerable interest due to its rich and diverse active functional groups and its antioxidant,antimicrobial,and adhesive properties.Recent research has significantly improved the performance of lignin-based hydrogels,suggesting their substantial potential in fields such as biomedicine,environmental science,and agriculture.This paper reviews the process of lignin extraction,systematically introduces synthesis strategies for preparing lignin-based hydrogels,and discusses the current state of research on these hydrogels in biomedical and environmental protection fields.It concludes by identifying the existing challenges in lignin hydrogel research and envisioning future prospects and development trends.
文摘Lignin is a significant secondary metabolite produced through the phenylpropanoid pathway.As a vital component of the plant cell wall,lignin affects various fruit characteristics,including size,seed quantity,and firmness.In this study,we conducted comprehensive identification and phylogenetic analysis of 265 Caffeic acid O-methyltransferase(COMT)genes across ten different plant species,including Vaccinium corymbosum and four other Vaccinium species.The results reveal that VcCOMT38 is a promising structural gene for the biosynthesis of lignin in blueberry.An in vitro enzymatic assay of VcCOMT38 demonstrated that it is a special enzyme in the lignin biosynthesis pathway and prefers to use caffeic acid as a substrate over 5-hydroxyferulic acid.Transient overexpression and silencing of VcCOMT38 in Vaccinium corymbosum‘Northland’fruits demonstrated that VcCOMT38 participates in lignin biosynthesis and contributes to both an increased number of immature seeds and enhanced fruit firmness.The heterologous overexpression of VcCOMT38 in Nicotiana benthamiana revealed that this gene could increase the lignin content and the syringyl/guaiacyl(S/G)ratio,which determines the maximum monomer yield during lignin depolymerization.These results highlight VcCOMT38 as a crucial gene in lignin biosynthesis and its potential for improving lignin production in industry through genetically modified woody plants.
基金supported by the National Natural Science Foundation of China(Nos.51603005,52403186 and 52573150)Fujian Provincial Natural Science Foundation of China(No.2024J011447)+1 种基金Natural Science Foundation of Xiamen,China(No.3502Z20227305)the Postdoctoral Fellowship Program of CPSF(No.GZC20240095)。
文摘Near-infrared(NIR)light-responsive shape memory polymers(SMPs)show great promise for biomedical applications,but conventional photothermal agents suffer from high cost,complex preparation,or poor biocompatibility,while lignin-based alternatives exhibit insufficient photothermal conversion efficiency.Herein,we developed a novel strategy to enhance photothermal performance of lignin through sequential demethylation modification and Fe^(3+)complexation for constructing NIR light responsive SMPs.Dealkaline lignin(DL)was first demethylated using iodocyclohexane to produce demethylated lignin(DDL)with increased catechol content,which was then incorporated into polycaprolactone-based polyurethane synthesis followed by Fe^(3+)complexation.Results showed that DDL-Fe^(3+)complexes have significantly enhanced photothermal conversion performance,and the resulting PU-DDL+Fe^(3+)polyurethane with 0.5 wt%DDL content demonstrated a temperature increases of 39.8℃under 0.33 W·cm-2808 nm NIR irradiation.This excellent photothermal performance enables the shape-fixed PU-DDL+Fe^(3+)polyurethane to rapidly recover to its initial shape under NIR light irradiation.Additionally,PU-DDL+Fe^(3+)polyurethane exhibits good mechanical properties and biocompatibility,demonstrating significant biomedical application potential.
基金the National Natural Science Foundation of China(32171728 and 22008159)Wuhan Knowledge Innovation Project(2022020801020312).
文摘Developing on-demand biomass valorization represents an ideal path to alleviate the double burden of a sustainable energy-environment future,yet exploring tunable lignin-first chemistry to accomplish multifunctional water purification remains elusive.Herein,we report a versatile solvent-fractionation to construct heteroatom-doped multicolor lignin carbon quantum dots(CQDs)with the functions of bimodal pollutant sensing,metal-ionic visualization,and photocatalytic antibiotic dissociation.With the aid of oxidation cleavage and biphasic extraction,the underlying lignin features of molecular weight and functional linkages influence the quantum size and core-surface state of CQDs conferring the unique optical-structure-performance.The N,S co-doped blue-emitting CQDs via light-quenching offer the selective identification of Fe^(3+)-ions in a broad response range with an acceptable limit of detection.The addition of L-cysteine can efficiently restore the fluorescence of CQDs by forming a stable Fe^(3+)-L-cys complex.The green-emissive CQDs are facilely embedded into cellulose hydrogel to directly visualize the presence of metal-ions.A red-CQDs modified ternary ZnIn2S4(ZIS)composite is fabricated to achieve photocatalytic antibiotic removal with an efficiency of~85%.The excellent photo-generated electron and storage capabilities of CQDs improve the light-capturing,electron conduction,and charge carrier separation of ZIS.The reactive species are of importance to photocatalytic tetracycline oxidation,wherein the electron holes(h+)function as the main contributor followed by∙O_(2)^(-),1O2 and∙OH.The directly interfacial electron escaping-shuttling with the help of optimized electronic and energy-band structures is confirmed via electrochemical test and theoretical computation.We anticipate that the present work not only sheds substantial light to manipulate polychromatic lignin-based CQDs via a tailored solvent-engineering,but also presents an emerging green route of emphasizing biomass-water nexus.
基金funded by the National Natural Science Foundation of China (31760363)the Earmarked Fund for CARS (CARS-14-1-16)+1 种基金the Gansu Education Science and Technology Innovation Industry Support Program,China (2021CYZC-38)the Gansu Provincial Key Laboratory of Arid Land Crop Science,Gansu Agricultural University,China (GSCS-2020-Z6)。
文摘Lodging is a major constraint limiting oil flax production efficiency in northern China.Crop lodging susceptibility is closely related to stem lignin content,and the regulatory mechanisms by which nitrogen and potassium fertilization interactively influence lignin biosynthesis in oil flax stems require further investigation.Therefore,this study aimed to enhance lodging resistance and increase grain yield in oil flax.We examined the interactive effects of different nitrogen (75,150,and 225 kg N ha^(–1)) and potassium (60 and 90 kg K_(2)O ha^(–1)) fertilizer rates on lignin metabolism,lodging resistance,and grain yield during the 2022 and 2023 growing seasons.Results indicated that nitrogen and potassium fertilizer levels and their interactions promoted lignin accumulation,improved lodging resistance,and increased grain yield.Compared to the control (CK),the75–150 kg N ha^(–1) combined with 60 kg K_(2)O ha^(–1) treatments significantly enhanced the activities of key lignin-synthesizing enzymes (tyrosine ammonia-lyase (TAL),phenylalanine ammonia-lyase (PAL),cinnamyl alcohol dehydrogenase (CAD),and peroxidase (POD)) and upregulated the expression of 4CL1 and F5H3 genes,leading to a 29.63–43.30%increase in lignin content,improved stem bending strength and lodging resistance index,and a 23.27–32.34%increase in grain yield.Correlation analysis revealed that nitrogen and potassium fertilizers positively regulated enzyme activities and gene expression related to lignin biosynthesis,thereby facilitating lignin accumulation and enhancing stem mechanical strength and lodging resistance.Positive correlations were observed among lignin-related enzyme activities,gene expression,lodging resistance traits,and grain yield.In summary,the application of 75–150 kg N ha^(–1) in conjunction with 60 kg K_(2)O ha^(–1)promoted lignin biosynthesis and accumulation,enhanced lodging resistance,and increased grain yield in oil flax grown in the dryland farming region of central Gansu,China.Furthermore,this treatment provides a technical basis for cultivating stress-tolerant and high-yield oil flax in arid regions.
文摘Research-based on lignin as a bioproduct has grown due to its high availability,reactivity,physicochemical sta-bility,and abundance of different aromatic units.Lignin consists of various functional groups,which can react in various chemical reactions and serve as a raw material in various processes to obtain multiple products.These characteristics make lignin suitable for synthesizing products from natural raw materials,replacing fossil ones.Due to a high aromatic variety and complex structural arrangement,lignin isolation and fractionation are still challenging.The aim and novelty of this work was the modification of severity and enzymatic hydrolysis proce-dure on an industrial pre-treatment to improve by-products of birch processing as a raw material for the potential production of different products.Lignin from birch wood enzymatic hydrolysis was obtained and marked accord-ingly:HS(high severity),MS(medium severity),and LS(low severity)lignin.Samples were characterized by ash content,analytical pyrolysis,solubility,and viscosity.HS lignin was characterized by a relatively high carbohy-drate content(16%)and lower lignin content(77%).Meanwhile,LS lignin showed increased lignin content(83%)and reduced carbohydrate content(9%).It can be concluded that the delignification process greatly influ-ences the properties of the obtained lignin.HS lignin resulted in a lower polydispersity index(PDI)and more condensed structure,while LS lignin showed a higher PDI but a lower content of carbohydrates.Therefore,look-ing for a golden middle way is necessary whilefinding the conditions according to the usefield.
基金funded by Project Better Plastics—Plastics in a Circular Economy—PPS4(Circularity by Alternative Feedstocks)Grant agreement ID:POCI-01-0247-FEDER-046091RR was funded by FCT through the PhD grant with reference UI/BD/154446/2022.
文摘The growing environmental awareness,the search for alternatives to fossil resources,and the goal of achieving a circular economy have all contributed to the increasing valorization of biowaste to produce bio-based polymers and other high-value products.Among the various biowaste materials,lignin has gained significant attention due to its high aromatic carbon content,low cost,and abundance.Lignin is predominantly sourced as a byproduct from the paper industry,available in large quantities from hardwood and softwood,with variations in chemical structure and susceptibility to hydrolysis.This study focuses on softwood lignin obtained through the LignoForce^(TM) technology,comparing the thermal and chemical characteristics,and stability,of a recently produced batch with that of a batch that has been stored for four years.Additionally,the development of lignin-based thermoplastic polymer mixtures using Polyethylene Terephthalate Glycol(PET-G)and a blend of Polycarbonate and Acrylonitrile-Butadiene-Styrene(PC/ABS)with high lignin content(50–60 wt%)is explored,as well as the production of filaments for carbon fiber production.For this purpose,following melt mixing,the lignin-based mixtures were spun into filaments,which were subsequently subjected to thermal stabilization in an oxidative atmosphere.The lignin phase was well distributed in the PET-Gmatrix and the twomaterials presented a good interface,which further improved after thermal treatment under an oxidative atmosphere.After thermal treatment an increase in tensile modulus,tensile strength,and elongation at break of approximately 160%,200%,and 100%,respectively,was observed,confirming the good interface established,and consistent with structural changes such as cross-linking.Conversely,the PC/ABS blend did not form a good interface with the lignin domains after melt mixing.Although the interactions improved after thermal treatment,the tensile strength and elongation at break decreased by approximately 30%,while themodulus increased by approximately 20%.Overall,the good processability of the lignin/polymer mixtures into filaments,and their physical,chemical,and mechanical characterization before and after thermal oxidation are good indicators of the potential as precursors for carbon fiber production.
基金supported by Natural Science and Engineering Research Council of Canada(RGPIN-2017-06737)Canada Research Chairs program,the National Key Research and Development Program of China(2017YFD0601005,2022YFD0904201)+1 种基金the National Natural Science Foundation of China(51203075)the China Scholarship Council(Grant No.CSC202208320361).
文摘With the rapid development of flexible wearable electronics,the demand for stretchable energy storage devices has surged.In this work,a novel gradient-layered architecture was design based on single-pore hollow lignin nanospheres(HLNPs)-intercalated two-dimensional transition metal carbide(Ti_(3)C_(2)T_(x) MXene)for fabricating highly stretchable and durable supercapacitors.By depositing and inserting HLNPs in the MXene layers with a bottom-up decreasing gradient,a multilayered porous MXene structure with smooth ion channels was constructed by reducing the overstacking of MXene lamella.Moreover,the micro-chamber architecture of thin-walled lignin nanospheres effectively extended the contact area between lignin and MXene to improve ion and electron accessibility,thus better utilizing the pseudocapacitive property of lignin.All these strategies effectively enhanced the capacitive performance of the electrodes.In addition,HLNPs,which acted as a protective phase for MXene layer,enhanced mechanical properties of the wrinkled stretchable electrodes by releasing stress through slip and deformation during the stretch-release cycling and greatly improved the structural integrity and capacitive stability of the electrodes.Flexible electrodes and symmetric flexible all-solid-state supercapacitors capable of enduring 600%uniaxial tensile strain were developed with high specific capacitances of 1273 mF cm^(−2)(241 F g^(−1))and 514 mF cm^(−2)(95 F g^(−1)),respectively.Moreover,their capacitances were well preserved after 1000 times of 600%stretch-release cycling.This study showcased new possibilities of incorporating biobased lignin nanospheres in energy storage devices to fabricate stretchable devices leveraging synergies among various two-dimensional nanomaterials.
基金financial support of the National Natural Science Foundation of China(U23A6005,22038004 and 22178069).
文摘The emission of organic pollutants from the dye industry and medical treatment represents a significant threat to the quality of water resources and human health.The development of green,environmentally friendly and efficient photocatalysts for the removal of organic pollutants from the environment is of paramount importance in addressing these issues.Flower-like lignin-derived carbon(LC)/zinc oxide(ZnO)composites with controllable morphology were synthesized via a direct precipitation method.In this study,alkali lignin was employed as an anionic active agent to alter the molecular arrangement on the liquid surface during the synthesis reaction and to reduce the surface tension between mixtures,thereby forming a special stacked morphology,which was then used for the highly efficient removal of methylidene blue(MB)and tetracycline hydrochloride(TCH)in water under different light conditions.The formation mechanism of LC/ZnO and the degradation characteristics under different reaction conditions were investigated.The loading of LC can form composites with large specific surface area and rich porous structure.In addition,with the help of lignin,the morphology of ZnO was changed from a rod-like structure to a lamellar structure,and LC could effectively reduce the band gap of ZnO,which could improve the electron transfer rate in the photocatalytic process.The·O_(2)^(-)and·OH radicals generated under photoexcitation promoted the decomposition of pollutants.This study presents a simple,economical,and scalable method for the application of photocatalysts and explores new ways for the high-value application of industrial lignin.
基金National Natural Science Foundation of China,Grant/Award Numbers:32171717,32271814Natural Science Foundation of Tianjin Municipality,Grant/Award Numbers:24JCJQJC00030,22JCYBJC01560,23JCZDJC00630China Postdoctoral Science Foundation,Grant/Award Number:2023M740562。
文摘Carbon fibers(CFs)with notable comprehensive properties,such as light weight,high specific strength,and stiffness,have garnered considerable interest in both academic and industrial fields due to their diverse and advanced applications.However,the commonly utilized precursors,such as polyacrylonitrile and pitch,exhibit a lack of environmental sustainability,and their costs are heavily reliant on fluctuating petroleum prices.To meet the substantial market demand for CFs,significant efforts have been made to develop cost-effective and sustainable CFs derived from biomass.Lignin,the most abundant polyphenolic compound in nature,is emerging as a promising precursor which is well-suited for the production of CFs due to its renewable nature,low cost,high carbon content,and aromatic structures.Nevertheless,the majority of lignin raw materials are currently derived from pulping and biorefining industrial by-products,which are diverse and heterogeneous in nature,restricting the industrialization of lignin-derived CFs.This review classifies fossil-derived and biomass-derived CFs,starting from the sources and chemical structures of raw lignin,and outlines the preparation methods linked to the performance of lignin-derived CFs.A comprehensive discussion is presented on the relationship between the structural characteristics of lignin,spinning preparation,and structure-morphology-property of ligninderived CFs.Additionally,the potential applications of these materials in various domains,including energy,catalysis,composites,and other advanced products,are also described with the objective of spotlighting the unique merits of lignin.Finally,the current challenges faced and future prospects for the advancement of lignin-derived CFs are proposed.
基金National Natural Science Foundation of China (U23A6005 and 22078069)Project funded by China Postdoctoral Science Foundation (GZB20230172 and 2023M740748)。
文摘Electrochemical conversion of lignin for the production of high-value heterocyclic aromatic compounds has great potential.We demonstrate the targeted synthesis and cation modulation of NiCo_(2)O_(4)spinel nanoboxes,synthesized via cation exchange and calcination oxidation.These catalysts exhibit excellent efficacy in the electrocatalytic conversion of lignin model compounds,specifically 2-phenoxy-1-phenylethanol,into nitrogen-containing aromatics,achieving high conversion rates and selectivities.These catalysts were synthesized via a cation exchange and calcination oxidation process,using Prussian blue nanocubes as precursors.The porous architecture and polymetallic composition of the NiCo_(2)O_(4)spinel demonstrated superior performance in electrocatalytic oxidative coupling,achieving a 99.2 wt%conversion rate of the 2-phenoxy-1-phenylethanol with selectivities of 37.5 wt%for quinoline derivatives and 31.5 wt%for phenol.Key innovations include the development of a sustainable one-pot synthesis method for quinoline derivatives,the elucidation of a multistage reaction pathway involving CAO bond cleavage,hydroxyaldol condensation,and CAN bond formation,and a deeper mechanistic understanding derived from DFT simulations.This work establishes a new strategy for lignin valorization,offering a sustainable route to produce high-value nitrogen-containing aromatics from renewable biomass under mild conditions,without the need for additional reagents.
基金supported by National Natural Science Foundation of China(22178258,22308254)China Postdoctoral Science Foundation(2023M742593,2024T170642)+1 种基金Independent Innova-tion Fund of Tianjin University(2024XQM-0021)the Open Fund of the Key Laboratory of Functional Molecular Solids(FMS2023006)。
文摘Ni-based catalysts are widely applied in the hydrodeoxygenation of lignin derivatives via C-O cleavage for the production of cycloalkanes.However,they often have difficulty in achieving high activity under mild conditions and exhibit relatively poor stability,and rare studies focus on the cleavage of the stubborn interunit C-C linkages.To address this issue,we developed a Ni@AlPO_(4)/Al_(2)O_(3)catalyst in which the surface of Ni nanoparticles was decorated by AlPO_(4)species,demonstrating excellent catalytic activity and stability in the C-C and C-O cleavages.In the hydrodeoxygenation of guaiacol,this catalyst afforded99.1%conversion and 92.9%yield of cyclohexane under 1 MPa H_(2)at 230℃ for 2 h.More important,this catalyst maintained unchanged performance even after 6 runs with the conversion controlled at about50%,Mecha nistic investigations revealed that the moderate surface coverage of AlPO_(4)on Ni with the formation of Ni^(δ+)-AlPO_(4)interface significantly facilitated the conversion of methoxycyclohexanol and cyclohexanol to cyclohexane,whereas,excess coverage would also block the access to Ni site.Moreover,Ni@AlPO_(4)/Al_(2)O_(3)demonstrated broad applicability in the C-O cleavage of various typical lignin monomers and dimers into cycloalkanes.To our delight,this catalyst also displayed pretty good activity even in the simultaneous cleavage of C-C linkages and C-O bonds for the lignin-derived C-C dimers,achieving cycloalkanes as final products.As a consequence,a 27.1 wt%yield of monocycloalkanes was obtained in the depolymerization of poplar lignin with both C-C and C-O cleavages.
文摘Many strategies have been proposed to produce arenes from lignin as liquid fuel additives.However,the development of these methods is limited by the low yield of products,low atom utilization,and inefficient lignin depolymerization.Herein,we develop an energy-efficient synthetic method for the production of high-carbon-number arenes from sustainable lignin with a total yield of 23.1 wt%.Particularly,high carbon number arenes are obtained by fully utilizing the formaldehyde stabilizing additive and the methoxy group in lignin.The process begins with the reductive depolymerization of formaldehyde-stabilized lignin,followed by transmethylation between lignin monomers over Au/Nb_(2)O_(5) catalyst,and the Ru/Nb2O5-catalyzed hydrodeoxygenation.This work demonstrates the potential of value-added arenes production directly from lignin.
基金Sponsorship Program by CAST(2023QNRC001)University-Industry Collaborative Education Program(220901115200913,220901115201954)+2 种基金Hunan Provincial Natural Science Foundation of China(2022JJ40007)Jiangsu Agricultural Science and Technology Innovation Fund(CX(22)3047)the National Natural Science Foundation of China(32201491)。
文摘Carbon quantum dots are a new type of fluorescent nanomaterials with broad applications in drug delivery,bioimaging,solar cells,and photocatalysis due to their unique biocompatibility,optical properties and easy functionalization.In the meantime,because of its high carbon content,renewable nature,and environmental friendliness,lignin has drawn the attention of researchers as a desirable raw material for creating carbon quantum dots.Here we review the synthesis of carbon quantum dots from lignin,focusing on synthetic methods,properties,and applications in energy,and photocatalysis.Later,we propose some new development prospects from preparation methods,luminescence mechanism research,application,and commercial cost of lignin carbon quantum dots.Finally,based on this,the development prospects of this field are prospected and summarized.
基金funding support from Taishan Scholars Program of Shandong Province(tsqn201909132)National Natural Science Foundation of China(22208183)+1 种基金Startup Foundation from Qingdao Agricultural University(663-1120040,665-1119020)Technology development project from Jinan Shengquan Company(20233702031771)。
文摘Lignin has been proved to be a promising precursor for producing carbon foam.The thermal and chemistry properties of lignin during its thermal conversion make it quite unique comparing with other precursors,and the conversion parameters can clearly affect the properties of the derived products.Therefore,this study systematically investigated the effects of key carbonization parameters on the properties of the resulting carbon foam materials.The findings demonstrate that the performance of the self-shaping lignin-derived carbon foam is simultaneously influenced by the factors that carbonization temperature,heating rate,and carbonization duration.Specifically,the carbonization temperature and carbonization duration have a significant impact on the mechanical performance,where higher temperatures and long carbonization time improve compressive strength and specific strength.Moreover,the data revealed that elevated temperatures,rapid heating rates,and shortened carbonization periods collectively promoted the development of higher porosities and larger pore diameters within the carbon foam structure.Conversely,lower carbonization temperatures,slower heating rates,and extended carbonization durations facilitated the formation of microporous in the carbon foam.This study provides a scientific foundation for optimizing the production of lignin-derived carbon foam with tailored properties and performance characteristics.
基金supported by the National Research Foundation(NRF)of Korea,funded by the Korean Government(MSIT)(Grant No.RS-2023-00240043).
文摘As the most abundant aromatic bio-based polymer,lignin has great potential as a sustainable feedstock for building crosslinked thermoset polymers as bio-based adhesives.However,the potential of hardwood kraft lignin(HKL)is limited due to its poor crosslinking reactivity.Hence,for the first time,the present study reports the facile oxidation of HKL involving a redox reaction with silver-ammonia complexes([(AgNH3)2]+),primarily focusing on oxidation to produce reactive quinones and promote C-C linkages during reaction.This study aims to increases reactivity of oxidized HKL for effective crosslinking with monoethanolamine(MEA)for the development of bio-based wood adhesives.The characterization,including 13C-nuclear magnetic resonance(NMR)and Fourier transform infrared(FT-IR)spectroscopy,confirms the oxidation reaction,such as the formation of quinones(C=O)and subsequent crosslinking between the oxidized HKL molecules and MEA.Additionally,gel permeation chromatography(GPC)confirms the C-C and C-O linkages with increased molecular weight after oxidation,and is supported by differential scanning calorimetry(DSC)which shows the exothermic reaction due to the crosslinking of the oxidized HKL molecules via condensation to form C-C and C-O linkages.The crosslinked HKL/MEA-based adhesives underwent mild reaction and achieved a maximum dry shear strength of 0.77 MPa,which exceeds the standard requirement of 0.6 MPa.These findings demonstrate not only a one-pot oxidation for improving the reactivity of HKL using silver complexes,but also its facile crosslinking with MEA for sustainable bio-based wood adhesives.
文摘Oxidative catalysis enables lignin depolymerization to yield carbonyl-containing aromatic chemicals for sustainable lignocellulose valorization.The oxidative depolymerization of lignin requires high oxygen pressure and harsh conditions to trade off lignin’s structural complexity and limited solubility.Herein,we developed an oxidation system for lignin depolymerization using a single phosphomolybdic acid(H_(3)PMo_(12)O_(40))catalyst in acetic acid solvent to address the aforementioned issues.The entire catalytic system was operated under only 0.1 MPa O_(2) pressure,providing over 20 wt% of aromatic compounds containing aldehydes and carboxylic acids.Theoretical calculations combined with experimental analyses reveal structural transformations and redox behavior driven by the synergistic interaction between H_(3)PMo_(12)O_(40) and acetic acid.Mechanistic studies detected superoxide radicals,confirming the joint role of catalyst and solvent in oxygen activation,radicals stabilization,and enhanced reaction efficiency.A low-cost,commercially available catalyst with minimal oxygen demand offers a promising route to industrial-scale biomass refining.
文摘Developing favorable bio-based polymers that replace petroleum-based plastics is an essential environmental demand.Lignin is a by-product of the chemical pulping industry.It is a natural UV protection ingredient in broad-spectrum(UVA and UVB)sunscreens.It could be partially and selectively acetylated in a simple,fast,and more reliable process.In this work,a composite film was prepared with UV-resistant properties through a casting method.Bio-based cellulose acetate(CA)was employed as a major matrix while nano-acetylated kraft lignin(AL-NPs)was used as filler during synthesizing UV-shielding films loaded with various amounts(1–5 wt.%)of AL-NPs.Kraft lignin was acetylated through a simple and fast microwave-assisted process using acetic acid as a solvent and acetylating agent.The physicochemical and morphological characteristics of the prepared films were evaluated using different methods,including scanning electron microscopy(SEM),Fourier Transform Infrared Spectroscopy(FTIR),X-ray diffraction analysis(XRD),mechanical testing and contact angle measurement.The UV-Vis spectroscopy optical investigation of the prepared films revealed that AL-NPs in the CA matrix showed strong UV absorption.This feature demonstrated the effectiveness of our research in developing UV-resistant bio-based polymer films.Hence,the prepared films can be considered as successful candidates to be applied in packaging applications.
