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Nitrogen-doped Co_(3)O_(4) nanowires enable high-efficiency electrochemical oxidation of 5-hydroxymethylfurfural

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Chinese Chemical Letters 2022年第1期33卷 385-389页

作者： Mengxiao Sun Yue Wang Chunsen Sun Yan Qi Jia Cheng Yumei Song Lixue Zhang College of Chemistry and Chemical Engineering State Key Laboratory of Bio-fibers and Eco-textilesQingdao UniversityQingdao 266071China Guangdong Provincial Key Laboratory of Emergency Test for Dangerous Chemicals Institute of AnalysisGuangdong Academy of SciencesGuangzhou 510070China

Developing highly efficient and cost-effective catalysts for electrochemically oxidizing biomass-derived 5-hydroxymethylfurfural(hmf)into value-added 2,5-furandicarboxylic acid(FDCA)is of great importance.Herein,we report a controllable nitrogen doping strategy to significantly improve the catalytic activity of Co_(3)O_(4)nanowires for highly selective electro-oxidation of hmf into FDCA.The nitrogen doping leads to the generation of defects including nitrogen dopants and oxygen vacancies in Co_(3)O_(4)nanowires,which is conducive to the formation of catalytically active sites.As a result,the electro-oxidation potential for hmf is only 1.38 V(vs.RHE)when the current density reaches 50 mA/cm^(2).More importantly,the conversion rate of hmf is as high as 99.5%,and the yield of FDCA is up to 96.4%.

关键词： Electrochemical oxidation hmf FDCA Co_(3)O_(4) Nitrogen doping

Rh掺杂的Cu纳米线催化剂促进5-羟甲基糠醛电催化加氢

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Science Bulletin 2023年第19期68卷 2190-2199,M0004页

作者：张文飞齐宴宾赵渊葛胜鑫董磊沈建华江宏亮李春忠 Shanghai Engineering Research Center of Hierarchical Nanomaterials School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

生物质是世界上广泛存在的可再生资源,可以转化成高价值燃料和化学品.基于可再生能源产生的电力,将生物质衍生的5-羟甲基糠醛(hmf)电催化转化为2,5-呋喃二甲醇(Bhmf)具有重要的研究意义和应用价值.hmf在电转化过程中容易发生二聚反应,... 详细信息

生物质是世界上广泛存在的可再生资源,可以转化成高价值燃料和化学品.基于可再生能源产生的电力,将生物质衍生的5-羟甲基糠醛(hmf)电催化转化为2,5-呋喃二甲醇(Bhmf)具有重要的研究意义和应用价值.hmf在电转化过程中容易发生二聚反应,从而导致Bhmf的选择性较低,产物分离难度大.因此,探索获得高选择性Bhmf的高效催化体系极为重要.在此,本文报道了Rh掺杂的Cu纳米线催化剂,其在hmf电还原为Bhmf反应中表现出较高的转化率,且有效抑制了二聚反应的发生.动力学实验和原位光谱研究表明,Rh的引入可以有效促进水解离形成活性氢物种,促进5-羟甲基糠醛电催化加氢并抑制其二聚.此催化剂设计策略可以拓展到其他生物质衍生分子的电催化转化过程中.

关键词：催化剂设计高选择性活性氢水解离 hmf 可再生能源可再生资源催化转化

Etherification of hmf to biodiesel additives: The role of NH4+ confinement in Beta zeolites

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Journal of Energy Chemistry 2019年第9期28卷 114-121页

作者： Paola Lanzafame Georgia Papanikolaou Katia Barbera Gabriele Centi Siglinda Perathoner Departments of ChiBioFarAm and MIFT-Section of Industrial Chemistry University of Messina ERIC aisbl and CASPE-INSTM

The role of NH4^+ ion confinement in the catalytic etherification of hmf(5-hydroxymethylfurfural) with ethanol to biodiesel additives was evidenced by studying the catalytic behavior of NH4^+-Beta zeolites with SiO2/Al2O3 ratios of 25 and 75.In order to affect the strength and distribution of the acidic sites, as well as the mobility of NH4^+ ions in the zeolites cages, a secondary level of porosity was introduced in the NH4^+-Beta, presenting a different stability versus alkaline treatment, by using a thermal or an ultrasound assisted method.By analyzing the catalytic behavior in these two series of samples with respect to the changes in porosity by nonlocal density functional theory, structure by XRD, amount of acid sites by FT-IR and mobility of NH4^+ cations by measurements of reversible NH4^+ exchange capacity, was evidenced a decrease in catalytic performances both in terms of rate of hmf depletion and productivity to the main products, when confinement of the ammonium ions is lost due to the introduction of mesoporosity.The high capability of ammonium ions release, associated to the mono-dentate configuration,and the minor confinement effect inside the zeolite pore system, due to the more opened pores structure of mesoporous zeolites, hinders both the direct etherification of hmf to EMF [5-(ethoxymethyl)furan-2-carbaldehyde] and the parallel reaction pathway via acetalization, favoring the rapid desorption of the hmfDEA [5-(hydroxymethyl)furfural diethyl acetal] product out of the crystal and the consequent inhibition of the consecutive reactions to EMFDEA [5-(ethoxymethyl)furfural diethyl acetal] and EMF.

关键词： Ammonium ion Beta zeolite hmf etherification Confinement effect 5-(ethoxymethyl)furan-2-carbaldehyde

CFD simulation of homogeneous reaction characteristics of dehydration of fructose to hmf in micro-channel reactors

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Chinese Journal of Chemical Engineering 2018年第6期26卷 1340-1349页

作者： Xin Zhang Hui Liu Amar Samb Guofeng Wang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China Beijing Key Laboratory of Energy Environmental Catalysis Beijing University of Chemical Technology Beijing 100029 China China Tianchen Engineering Corporation (Beijing Branch) Beijing 100029 China

In this work the applicability of the micro-channel reactor technique to the production of promising platform chemical 5-hydroxymethyl furan(hmf) from fructose in aqueous solution is systemically investigated by performing CFD simulations.Influential factors including solvents,residence time distribution of reaction mixtures,heat transfer conditions and micro-channel configurations are evaluated in terms of the reaction performance indices,i.e.,conversion of fructose,hmf selectivity and yield.A scale-up method from a single channel to a multiple channel reactor is also proposed.It is demonstrated that:1) at the single channel scale,controlling residence times and temperature distribution of the reaction mixture within the channel is crucial for enhancing the reaction performance,while different channel configurations lead to marginal improvements;2) for the scaling-up of the reaction process,a reactor module containing 15 circular parallel channels could be used as module blocks,which can be stacked one by one to meet the required reactor performance and production capacity.The present results show that micro-reactors are quite suitable for hmf production.

关键词：反应特征 hmf CFD 反应堆隧道果糖脱水同类

One-pot synthesis of 5-hydroxymethylfurfural from glucose over zirconium doped mesoporous KIT-6

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Chinese Journal of Chemical Engineering 2018年第6期26卷 1270-1277页

作者： Chongwen Jiang Jundong Zhu Bing Wang Lu Li Hong Zhong College of Chemistry and Chemical Engineering Central South University Changsha 410083 China Hunan Provincial Key Laboratory of Efficient and Clean Utilization of Manganese Resources Central South University Changsha 410083 China

Zirconium doped mesoporous KIT-6 samples with different Si/Zr ratios were synthesized by the direct hydrothermal method.Various characterization techniques confirm that highly distributed ZrO_2 nanoparticles and multicoordinated Zr^(4+) species are incorporated in the mesoporous composites.One-pot synthesis of 5-hydroxymethylfurfura(hmf) from glucose was examined in the presence of Zr-KIT-6(20) the molar ratio of Si to Zr is 20 under aqueous system.The effects of temperature,reaction time,catalyst dosage and biphasic solvent system on the conversion of glucose and the hmf yield were investigated.It was found that the glucose conversion and the hmf yield have been improved from 54.8% to 79.0% and from 19.5% to 34.5% in the biphasic MIBK-water system,respectively.Both the acidity of Zr-KIT-6(20) and the biphasic MIBK-water system are responsible for the improved performance of glucose dehydration to hmf.

关键词：葡萄糖合成锆反应时间分布式 hmf 催化剂热水

Activity origin and alkalinity effect of electrocatalytic biomass oxidation on nickel nitride

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Journal of Energy Chemistry 2021年第10期30卷 179-185,I0006页

作者： Bo Zhou Chung-Li Dong Yu-Cheng Huang Nana Zhang Yandong Wu Yuxuan Lu Xu Yue Zhaohui Xiao Yuqin Zou Shuangyin Wang State Key Laboratory of Chem/Bio-Sensing and Chemometrics Provincial Hunan Key Laboratory for Graphene Materials and DevicesCollege of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082HunanChina Department of Physics Tamkang UniversityNew Taipei City 25137TaiwanChina

Electro-oxidation of 5-hydroxymethylfurfural(hmfOR)is a promising green approach to realize the conversion of biomass into value-added chemicals.However,considering the complexity of the molecular structure of hmf,an in-depth understanding of the electrocatalytic behavior of hmfOR has rarely been investigated.Herein,the electrocatalytic mechanism of hmfOR on nickel nitride(Ni3 N)is elucidated by operando X-ray absorption spectroscopy(XAS),in situ Raman,quasi in situ X-ray photoelectron spectroscopy(XPS),and operando electrochemical impedance spectroscopy(EIS),respectively.The activity origin is proved to be Ni^(2+δ)N(OH)ads generated by the adsorbed hydroxyl group.Moreover,hmfOR on Ni3 N relates to a two-step reaction:Initially,the applied potential drives Ni atoms to lose electrons and adsorb OH-after 1.35 VRHE,giving rise to Ni^(2+δ)N(OH)ads with the electrophilic oxygen;then Ni^(2+δ)N(OH)ads seizes protons and electrons from hmf and leaves as H_(2) O spontaneously.Furthermore,the high electrolyte alkalinity favors the hmfOR process due to the increased active species(Ni^(2+δ)N(OH)ads)and the enhanced adsorption of hmf on the Ni3 N surface.This work could provide an in-depth understanding of the electrocatalytic mechanism of hmfOR on Ni3 N and demonstrate the alkalinity effect of the electrolyte on the electrocatalytic performance of hmfOR.

关键词： Biomass electro-oxidation Activity origin Alkalinity effect Operando techniques hmf

Hemicellulose in corn straw:Extracted from alkali solution and produced5-hydroxymethyl furfural in HCOOH/HCOONa buffer solution

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Chinese Journal of Chemical Engineering 2016年第12期24卷 1786-1792页

作者： Yan Li Hongxian Fan Xueqing Yu Songmei Zhang Gang Li Hebei Provincial Key Lab of Green Chemical Technology and High Efficient Energy Saving School of Chemical Engineering and Technology Hebei University of Technology

Hemicellulose in corn straw is a group of complex heteropolysaccharides which are composed of different sugar units, including mannans, xylans, arabinans and galactans. This study developed a simple and practical process for production of 5-hydroxymethyl furfural(hmf) using hemicellulose that was extracted from corn straw. In the hemicellulose degradation process HCOOH/HCOONa was used as buffer solution, and the optimum conditions for maximum hmf yield were explored. Various extraction conditions including NaOH concentration, reaction time,temperature, solid-to-liquid ratio and precipitant were tested for hemicellulose obtaining, giving the optimum condition of 55 °C, 4 h, solid-to-liquid ratio of 1:10, 1.5 mol·L^(-1) NaOH solution and ethanol as precipitant with the yield of 34.16%. Dehydration of hemicellulose under HCOOH/HCOONa buffer solution process, using solution medium of pH = 0.8 hydrolyzed hemicellulose in corn straw at 190 °C after 190 min and 82% of hmf yield was achieved.

关键词： Hemicellulose hmf 降级缓冲区答案 ELSD

Rapid conversion of cellulose to 5-hydroxymethylfurfural using single and combined metal chloride catalysts in ionic liquid

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燃料化学学报 2013年第2期41卷 214-222页

作者： Hussein Abou-Yousef El Barbary Hassan Philip Steele Department of Forest Products Mississippi State University Cellulose & Paper Department National Research CenterDokkiCairoEgypt

Direct conversion of cellulose into 5-hydroxymethylfurfural(hmf) was performed by using single or combined metal chloride catalysts in 1-ethyl-3-methylimidazolium chloride(Cl) ionic liquid.Our study demonstrated formation of 2-furyl hydroxymethyl ketone(FHMK),and furfural(FF) simultaneously with the formation of hmf.Various reaction parameters were addressed to optimize yields of furan derivatives produced from cellulose by varying reaction temperature,time,and the type of metal chloride catalyst.Catalytic reaction by using FeCl3 resulted in 59.9% total yield of furan derivatives(hmf,FHMK,and FF) from cellulose.CrCl3 was the most effective catalyst for selective conversion of cellulose into hmf(35.6%) with less concentrations of FHMK,and FF.Improving the yields of furans produced from cellulose could be achieved via reactions catalyzed by different combinations of two metal chlorides.Further optimization was carried out to produce total furans yield 75.9% by using FeCl3/CuCl2 combination.CrCl3/CuCl2 was the most selective combination to convert cellulose into hmf(39.9%) with total yield(63.8%) of furans produced from the reaction.The temperature and time of the catalytic reaction played an important role in cellulose conversion,and the yields of products.Increasing the reaction temperature could enhance the cellulose conversion and hmf yield for short reaction time intervals(5~20 min).

关键词：化学动力学燃料化学理论 EMIM hmf

Selective hydrogenolysis of 5-hydroxymethylfurfural to 2,5-dimethylfuran over Co_3O_4 catalyst by controlled reduction

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Journal of Energy Chemistry 2019年第3期28卷 34-41页

作者： Dan Li Qiying Liu Changhui Zhu Haiyong Wang Chunhua Cui Chenguang Wang Longlong Ma Nano Science and Technology Institute University of Science and Technology of China Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development CAS Key Laboratory of Renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Sciences University of Chinese Academy of Sciences

2,5-dimethyfuran(DMF), which is produced from 5-hydroxymethyfurfural(hmf) by hydrodeoxygenation(HDO), is a high quality fuel due to the high heating value, the high octane number and the suitable boiling point. Selective hydrogenation of hmf into liquid fuel DMF has been widely researched. In this paper, Co_3O_4 catalyst was prepared by co-precipitation and was reduced at different temperatures to form Co–CoO_x catalysts. The characterization of catalysts was tested by XRD, TEM, XPS, TPR, BET and NH3-TPD.Co–CoO_x possessed a high amount of Co metal and CoO_x acidic sites, wherein Co worked as the active hydrogenation sites and CoO_x acted as the acid promoter to facilitate the selective HDO of hmf to DMF.The synergistic effect of Co–CoO_x is the key for HDO of hmf, obtaining 83.3% of DMF yield at 170 °C, 12 h and the reduction temperature of 400 °C. This method not only saves the catalyst cost, but also promotes the utilization of biomass energy.

关键词： hmf DMF Co3O4 catalyst Hydrogenolysis