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Multi-functional layered double hydroxides supported by nanoporous gold toward overall hydrazine splitting 被引量:1
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作者 Yongji Qin Huijie Cao +8 位作者 Qian Liu Shaoqing Yang Xincai Feng Hao Wang Meiling Lian Dongxing Zhang Hua Wang Jun Luo Xijun Liu frontiers of chemical science and engineering SCIE EI CSCD 2024年第1期61-69,共9页
Layered double hydroxides have demonstrated great potential for the oxygen evolution reaction,which is a crucial half-reaction of overall water splitting.However,it remains challenging to apply layered double hydroxid... Layered double hydroxides have demonstrated great potential for the oxygen evolution reaction,which is a crucial half-reaction of overall water splitting.However,it remains challenging to apply layered double hydroxides in other electrochemical reactions with high efficiency and stability.Herein,we report two-dimensional multifunctional layered double hydroxides derived from metalorganic framework sheet precursors supported by nanoporous gold with high porosity,which exhibit appealing performances toward oxygen/hydrogen evolution reactions,hydrazine oxidation reaction,and overall hydrazine splitting.The as-prepared catalyst only requires an overpotential of 233 mV to reach 10 mA·cm^(-2) toward oxygen evolution reaction.The overall hydrazine splitting cell only needs a cell voltage of 0.984 V to deliver 10 mA·cm^(-2),which is far more superior than that of the overall water splitting system(1.849 V).The appealing performances of the catalyst can be contributed to the synergistic effect between the metal components of the layered double hydroxides and the supporting effect of the nanoporous gold substrate,which could endow the sample with high surface area and excellent conductivity,resulting in superior activity and stability. 展开更多
关键词 layered double hydroxide oxygen evolution reaction hydrazine oxidation reaction overall hydrazine splitting hydrogen production
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High-yield production of porous carbon spheres derived from enzymatic hydrolysis lignin for zinc ion hybrid capacitors 被引量:1
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作者 Tao Huang Xihong Zu +3 位作者 Jianhui Ma Wenbin Jian Xueqing Qiu Wenli Zhang frontiers of chemical science and engineering SCIE EI CSCD 2024年第2期127-136,共10页
The widespread implementation of supercapacitors is hindered by the limited energy density and the pricey porous carbon electrode materials.The cost of porous carbon is a significant factor in the overall cost of supe... The widespread implementation of supercapacitors is hindered by the limited energy density and the pricey porous carbon electrode materials.The cost of porous carbon is a significant factor in the overall cost of supercapacitors,therefore a high carbon yield could effectively mitigate the production cost of porous carbon.This study proposes a method to produce porous carbon spheres through a spray drying technique combined with a carbonization process,utilizing renewable enzymatic hydrolysis lignin as the carbon source and KOH as the activation agent.The purpose of this study is to examine the relationship between the quantity of activation agent and the development of morphology,pore structure,and specific surface area of the obtained porous carbon materials.We demonstrate that this approach significantly enhances the carbon yield of porous carbon,achieving a yield of 22%in contrast to the conventional carbonization-activation method(9%).The samples acquired through this method were found to contain a substantial amount of mesopores,with an average pore size of 1.59 to 1.85 nm and a mesopore ratio of 25.6%.Additionally,these samples showed high specific surface areas,ranging from 1051 to 1831 m2·g^(−1).Zinc ion hybrid capacitors with lignin-derived porous carbon cathode exhibited a high capacitance of 279 F·g^(−1) at 0.1 A·g^(−1) and an energy density of 99.1 Wh·kg^(−1) when the power density was 80 kW·kg^(−1).This research presents a novel approach for producing porous carbons with high yield through the utilization of a spray drying approach. 展开更多
关键词 enzymatic hydrolysis lignin porous carbon spheres spray drying zinc ion hybrid capacitors
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Advancing oxygen separation:insights from experimental and computational analysis of La_(0.7)Ca_(0.3)Co_(0.3)Fe_(0.6)M_(0.1)O_(3-δ)(M=Cu,Zn)oxygen transport membranes
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作者 Guoxing Chen Wenmei Liu +10 位作者 Marc Widenmeyer Xiao Yu Zhijun Zhao Songhak Yoon Ruijuan Yan Wenjie Xie Armin Feldhoff Gert Homm Emanuel Ionescu Maria Fyta Anke Weidenkaff frontiers of chemical science and engineering SCIE EI CSCD 2024年第6期17-29,共13页
In this study,perovskite-type La_(0.7)Ca_(0.3)Co_(0.3)Fe_(0.6)M_(0.1)O_(3-δ)(M=Cu,Zn)powders were synthesized using a scalable reverse co-precipitation method,presenting them as novel materials for oxygen transport m... In this study,perovskite-type La_(0.7)Ca_(0.3)Co_(0.3)Fe_(0.6)M_(0.1)O_(3-δ)(M=Cu,Zn)powders were synthesized using a scalable reverse co-precipitation method,presenting them as novel materials for oxygen transport membranes.The comprehensive study covered various aspects including oxygen permeability,crystal structure,conductivity,morphology,CO_(2) tolerance,and long-term regenerative durability with a focus on phase structure and composition.The membrane La_(0.7)Ca_(0.3)Co_(0.3)Fe_(0.6)M_(0.1)O_(3-δ)exhibited high oxygen permeation fluxes,reaching up to 0.88 and 0.64 mL·min^(−1)·cm^(−2) under air/He and air/CO_(2) gradients at 1173 K,respectively.After 1600 h of CO_(2) exposure,the perovskite structure remained intact,showcasing superior CO_(2) resistance.A combination of first principles simulations and experimental measurements was employed to deepen the understanding of Cu/Zn substitution effects on the structure,oxygen vacancy formation,and transport behavior of the membranes.These findings underscore the potential of this highly CO_(2)-tolerant membrane for applications in high-temperature oxygen separation.The enhanced insights into the oxygen transport mechanism contribute to the advancement of next-generation membrane materials. 展开更多
关键词 PEROVSKITE oxygen permeation MEMBRANE oxygennionsdiffusiono xygen vacancy formation energy energy barrier
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Synthetic auxotrophs accelerate cell factory development through growth-coupled models
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作者 Liangpo Li Linwei Yu +3 位作者 Xinxiao Sun Qipeng Yuan Xiaolin Shen Jia Wang frontiers of chemical science and engineering SCIE EI CSCD 2024年第9期73-87,共15页
The engineering of microbial cell factories for the production of high-value chemicals from renewable resources presents several challenges,including the optimization of key enzymes,pathway fluxes and metabolic networ... The engineering of microbial cell factories for the production of high-value chemicals from renewable resources presents several challenges,including the optimization of key enzymes,pathway fluxes and metabolic networks.Addressing these challenges involves the development of synthetic auxotrophs,a strategy that links cell growth with enzyme properties or biosynthetic pathways.This linkage allows for the improvement of enzyme properties by in vivo directed enzyme evolution,the enhancement of metabolic pathway fluxes under growth pressure,and remodeling of metabolic networks through directed strain evolution.The advantage of employing synthetic auxotrophs lies in the power of growth-coupled selection,which is not only high-throughput but also labor-saving,greatly simplifying the development of both strains and enzymes.Synthetic auxotrophs play a pivotal role in advancing microbial cell factories,offering benefits from enzyme optimization to the manipulation of metabolic networks within single microbes.Furthermore,this strategy extends to coculture systems,enabling collaboration within microbial communities.This review highlights the recently developed applications of synthetic auxotrophs as microbial cell factories,and discusses future perspectives,aiming to provide a practical guide for growth-coupled models to produce value-added chemicals as part of a sustainable biorefinery. 展开更多
关键词 synthetic auxotrophs growth-coupled directed enzyme evolution pathway flux directed strain evolution COCULTURE
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Insight into the adsorption behavior and mechanism of trace impurities from H_(2)O_(2) solution on functionalized zirconia by tuning the structure of amino groups
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作者 Yu Meng Yitong Wang +2 位作者 Guozhu Li Guozhu Liu Li Wang frontiers of chemical science and engineering SCIE EI CSCD 2024年第5期83-94,共12页
Primary,secondary and tertiary amino-functionalized zirconia(ZrO_(2)-NH_(2),ZrO_(2)-NH and ZrO_(2)-N)was synthesized by the postgrafting method for the adsorption removal of typical metallic ions,phosphate and total o... Primary,secondary and tertiary amino-functionalized zirconia(ZrO_(2)-NH_(2),ZrO_(2)-NH and ZrO_(2)-N)was synthesized by the postgrafting method for the adsorption removal of typical metallic ions,phosphate and total oxidizable carbon from a real H_(2)O_(2) solution.ZrO_(2)-NH_(2),ZrO_(2)-NH and ZrO_(2)-N exhibited similar pore sizes and sequentially increased zeta potentials.The adsorption results of single and binary simulated solutions showed that the removal efficiency increased in the order of Fe^(3+)>Al^(3+)>Ca^(2+)>Na^(+).There is competitive adsorption between metallic ions,and Fe^(3+) has an advantage over the other metals,with a removal efficiency of 90.7%.The coexisting phosphate could promote the adsorption of metallic ions,while total oxidizable carbon had no effect on adsorption.The adsorption results of the real H_(2)O_(2)solution showed that ZrO_(2)-NH_(2) exhibited the best adsorption affinity for metallic ions,as did phosphate and total oxidizable carbon,with a total adsorption capacity of 120.9 mg·g_(-1).Density functional theory calculations revealed that the adsorption process of metallic ions involves electron transfer from N atoms to metals and the formation of N-metal bonds. 展开更多
关键词 adsorption metallic ion PHOSPHATE total oxidizable carbon ZIRCONIA H_(2)O_(2)
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Excitonic devices based on two-dimensional transition metal dichalcogenides van der Waals heterostructures
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作者 Yulun Liu Yaojie Zhu +6 位作者 Zuowei Yan Ruixue Bai Xilin Zhang Yanbo Ren Xiaoyu Cheng Hui Ma Chongyun Jiang frontiers of chemical science and engineering SCIE EI CSCD 2024年第2期41-67,共27页
Excitonic devices are an emerging class of technology that utilizes excitons as carriers for encoding, transmitting, and storing information. Van der Waals heterostructures based on transition metal dichalcogenides of... Excitonic devices are an emerging class of technology that utilizes excitons as carriers for encoding, transmitting, and storing information. Van der Waals heterostructures based on transition metal dichalcogenides often exhibit a type II band alignment, which facilitates the generation of interlayer excitons. As a bonded pair of electrons and holes in the separation layer, interlayer excitons offer the chance to investigate exciton transport due to their intrinsic out-of-plane dipole moment and extended exciton lifetime. Furthermore, interlayer excitons can potentially analyze other encoding strategies for information processing beyond the conventional utilization of spin and charge. The review provided valuable insights and recommendations for researchers studying interlayer excitonic devices within van der Waals heterostructures based on transition metal dichalcogenides. Firstly, we provide an overview of the essential attributes of transition metal dichalcogenide materials, focusing on their fundamental properties, excitonic effects, and the distinctive features exhibited by interlayer excitons in van der Waals heterostructures. Subsequently, this discourse emphasizes the recent advancements in interlayer excitonic devices founded on van der Waals heterostructures, with specific attention is given to the utilization of valley electronics for information processing, employing the valley index. In conclusion, this paper examines the potential and current challenges associated with excitonic devices. 展开更多
关键词 excitonic devices van der Waals heterostructures transition metal dichalcogenides interlayer excitons valley-Hall effect OPTOELECTRONICS
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Continuous flow pyrolysis of virgin and waste polyolefins:a comparative study,process optimization and product characterization
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作者 Ecrin Ekici Güray Yildiz +3 位作者 Magdalena Joka Yildiz Monika Kalinowska ErolŞeker Jiawei Wang frontiers of chemical science and engineering SCIE EI CSCD 2024年第6期133-149,共17页
Under optimal process conditions,pyrolysis of polyolefins can yield ca.90 wt%of liquid product,i.e.,combination of light oil fraction and heavier wax.In this work,the experimental findings reported in a selected group... Under optimal process conditions,pyrolysis of polyolefins can yield ca.90 wt%of liquid product,i.e.,combination of light oil fraction and heavier wax.In this work,the experimental findings reported in a selected group of publications concerning the non-catalytic pyrolysis of polyolefins were collected,reviewed,and compared with the ones obtained in a continuously operated bench-scale pyrolysis reactor.Optimized process parameters were used for the pyrolysis of waste and virgin counterparts of high-density polyethylene,low-density polyethylene,polypropylene and a defined mixture of those(i.e.,25:25:50 wt%,respectively).To mitigate temperature drops and enhance heat transfer,an increased feed intake is employed to create a hot melt plastic pool.With 1.5 g·min^(-1) feed intake,1.1 L·min^(-1) nitrogen flow rate,and a moderate pyrolysis temperature of 450℃,the formation of light hydrocarbons was favored,while wax formation was limited for polypropylene-rich mixtures.Pyrolysis of virgin plastics yielded more liquid(maximum 73.3 wt%)than that of waste plastics(maximum 66 wt%).Blending polyethylenes with polypropylene favored the production of liquids and increased the formation of gasoline-range hydrocarbons.Gas products were mainly composed of C3 hydrocarbons,and no hydrogen production was detected due to moderate pyrolysis temperature. 展开更多
关键词 waste plastics POLYOLEFINS chemical recycling PYROLYSIS alternative fuels WASTE-TO-ENERGY
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Optimizing support acidity of NiMo catalysts for increasing the yield of benzene, toluene and xylene in tetralin hydrocracking
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作者 Feng Chen Jianing Huo +2 位作者 Liang Zhao Jinsen Gao Chunming Xu frontiers of chemical science and engineering SCIE EI CSCD 2024年第1期71-84,共14页
To enhance the yields of benzene,toluene,and xylene in tetralin hydrocracking,the effect of the support acid properties of NiMo catalysts on hydrocracking performance of tetralin were investigated in this study.NaY ze... To enhance the yields of benzene,toluene,and xylene in tetralin hydrocracking,the effect of the support acid properties of NiMo catalysts on hydrocracking performance of tetralin were investigated in this study.NaY zeolites were modified by hydrothermal treatment to form USY zeolites at different temperatures and adjust the type and amount of acid.In addition,H-Beta was loaded into the USY to further adjust the acidic properties of the catalysts.The result shows that when the total B acid content of the catalyst is maintained between 150 and 200μmol·g^(-1),the total acid amount is maintained between 1.7 and 1.9 mmol·g^(-1),and the L/B(L and B acids)ratio is maintained between 1.5 and 2,the catalysts have favorable performances on tetralin hydrocracking.Under this condition,the catalysts have a yield of benzene,toluene,and xylene higher than 30 wt%and a selectivity for benzene,toluene,and xylene higher than 35%.The tetralin conversion is greater than 85 wt%.The AB6 catalyst obtains the best hydrocracking effect with the conversion of tetralin reaching 90.24 wt%,the yields of benzene,toluene,and xylene reaching 33.58 wt%,and the selectivity of benzene,toluene,and xylene reaching 37.21%,respectively. 展开更多
关键词 HYDROCRACKING TETRALIN BENZENE toluene and xylene acid properties reaction pathways
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Degradation pathways of amino acids during thermal utilization of biomass: a review
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作者 Mubarak Al-Kwradi Mohammednoor Altarawneh frontiers of chemical science and engineering SCIE EI CSCD 2024年第7期67-95,共29页
Amino acids are important nitrogen carriers in biomass and entail a broad spectrum of industrial uses,most notably as food additives,pharmaceutical ingredients,and raw materials for bio-based plastics.Attaining detail... Amino acids are important nitrogen carriers in biomass and entail a broad spectrum of industrial uses,most notably as food additives,pharmaceutical ingredients,and raw materials for bio-based plastics.Attaining detailed information in regard to the fragmentation of amino acids is essential to comprehend the nitrogen transformation chemistry at conditions encountered during hydrothermal and pyrolytic degradation of biomass.The underlying aim of this review is to survey literature studies pertinent to the complex structures of amino acids,their formation yields from various categories of biomass,and their fragmentation routes at elevated temperatures and in the aqueous media.Two predominant degradation reactions ensue in the decomposition of amino acids,namely deamination and decarboxylation.Notably,minor differences in structure can greatly affect the fate for each amino acid.Moreover,amino acids,being nitrogen-rich compounds,play pivotal roles across various fields.There is a growing interest in producing varied types and configurations of amino acids.Microbial fermentation appears to a viable approach to produce amino acids at an industrial scale.One innovative method under investigation is catalytic synthesis using renewable biomass as feedstocks.Such a method taps into the inherent nitrogen in biomass sources like chitin and proteins,eliminating the need for external nitrogen sources.This environmentally friendly approach is in line with green chemistry principles and has been gathering momentum in the scientific community. 展开更多
关键词 amino acids PYROLYSIS BIOMASS NITROGEN MECHANISMS BIOENERGY
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Life cycle assessment of homogeneous Fenton process as pretreatment for refractory pharmaceutical wastewater
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作者 Maojun Zou Jie Wei +4 位作者 Yuanyuan Qian Yanjing Xu Zhihuang Fang Xuejing Yang Zhiyuan Wang frontiers of chemical science and engineering SCIE EI CSCD 2024年第5期1-11,共11页
The applicability of the life cycle assessment(LCA)to the Fenton process should be considered not only at the laboratory-scale but also at the full-scale.In this study,the LCA process was applied to evaluate the homo-... The applicability of the life cycle assessment(LCA)to the Fenton process should be considered not only at the laboratory-scale but also at the full-scale.In this study,the LCA process was applied to evaluate the homo-geneous Fenton process for the treatment of high salinity pharmaceutical wastewater.The potential environmental impacts were calculated using Simapro software implemen-ting the CML 2001 methodology with normalization factors of 1995 world.Foreground data obtained directly from the full-scale wastewater treatment plant and labora-tory were used to conduct a life cycle inventory analysis,ensuring highly accurate results.By normalized results,the Fenton process reveals sensitive indicators,primarily toxi-city indicators(human toxicity,freshwater aquatic toxicity,and marine aquatic toxicity),as well as acidification and eutrophication impacts,contributed by hydrogen peroxide and iron sludge incineration,respectively.Overall,hydrogen peroxide and iron sludge incineration contribute significantly,accounting for at least 78%of these indicators.In sludge treatment phase,treatment of iron mud and infrastructure of hazardous waste incineration plants were the key contributors of environmental impacts,adding up to more than 95%.This study suggests the need to develop efficient oxidation processes and effective iron sludge treatment methods to reduce resource utilization and improve environmental benefits. 展开更多
关键词 advanced oxidation processes FULL-SCALE life cycle assessment Fenton process pharmaceutical high-salinity wastewater
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Preparation of biomass-derived carbon loaded with MnO_(2) as lithium-ion battery anode for improving its reversible capacity and cycling performance
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作者 Likai Zhu Huaping Lin +2 位作者 Wenli Zhang Qinhui Wang Yefeng Zhou frontiers of chemical science and engineering SCIE EI CSCD 2024年第1期107-120,共14页
Biomass-derived carbon materials for lithiumion batteries emerge as one of the most promising anodes from sustainable perspective.However,improving the reversible capacity and cycling performance remains a long-standi... Biomass-derived carbon materials for lithiumion batteries emerge as one of the most promising anodes from sustainable perspective.However,improving the reversible capacity and cycling performance remains a long-standing challenge.By combining the benefits of K2CO_(3) activation and KMnO_(4) hydrothermal treatment,this work proposes a two-step activation method to load MnO_(2) charge transfer onto biomass-derived carbon(KAC@MnO_(2)).Comprehensive analysis reveals that KAC@MnO_(2) has a micro-mesoporous coexistence structure and uniform surface distribution of MnO_(2),thus providing an improved electrochemical performance.Specifically,KAC@MnO_(2) exhibits an initial chargedischarge capacity of 847.3/1813.2 mAh·g^(-1) at 0.2 A·g^(-1),which is significantly higher than that of direct pyrolysis carbon and K2CO_(3) activated carbon,respectively.Furthermore,the KAC@MnO_(2) maintains a reversible capacity of 652.6 mAh·g^(-1) after 100 cycles.Even at a high current density of 1.0 A·g^(-1),KAC@MnO_(2) still exhibits excellent long-term cycling stability and maintains a stable reversible capacity of 306.7 mAh·g^(-1) after 500 cycles.Compared with reported biochar anode materials,the KAC@MnO_(2) prepared in this work shows superior reversible capacity and cycling performance.Additionally,the Li+insertion and de-insertion mechanisms are verified by ex situ X-ray diffraction analysis during the chargedischarge process,helping us better understand the energy storage mechanism of KAC@MnO_(2). 展开更多
关键词 biomass-derived carbon MnO_(2) lithium-ion batteries anode material high reversible capacity
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Construction of spinel/biochar film/honeycomb monolithic catalyst for photothermal catalytic oxidation of VOCs
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作者 Xikai Lu Chunyan Zhang +4 位作者 Meng Wu Wenjie Liu Bin Xue Chao Yao Xiazhang Li frontiers of chemical science and engineering SCIE EI CSCD 2024年第9期61-71,共11页
Photothermal catalytic oxidation emerges as a promising method for the removal of volatile organic compounds(VOCs).Herein,via sol-gel impregnation method,spinel CuMn_(2)O_(4)was coated on attapulgite honeycombs with i... Photothermal catalytic oxidation emerges as a promising method for the removal of volatile organic compounds(VOCs).Herein,via sol-gel impregnation method,spinel CuMn_(2)O_(4)was coated on attapulgite honeycombs with integrating biochar(BC)film as the second carrier,using chestnut shell as complexation agent.Various mass ratios of CuMn_(2)O_(4)to chestnut shell was modulated to investigate the catalytic toluene degradation performance.Results indicated that the monolithic CuMn_(2)O_(4)/BC/honeycomb catalyst demonstrated superior photothermal catalytic toluene degradation with a low T90(temperature at 90%degradation)of 263℃ when the mass ratio of CuMn_(2)O_(4)to biomass was 1:4.The addition of BC film substantially increased the honeycomb's specific surface area and improved the photothermal conversion of spinel,leading to enhanced photothermal catalytic activity.This study presents a cost-effective strategy for eliminating industrial VOCs using clay-biomass based monolithic catalyst. 展开更多
关键词 CuMn_(2)O_(4) BIOCHAR photothermal catalysis attapulgite honeycomb volatile organic compound
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Segregation of binary particles in gas-solid fluidized bed
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作者 Yaxiong Yu Feng Lu +2 位作者 Xuan He Fei Wei Chenxi Zhang frontiers of chemical science and engineering SCIE EI CSCD 2024年第6期113-121,共9页
Particle segregation and mixing behavior play a crucial role in industrial processes.This study investigates the saturated jetsam fraction,which indicates the maximum capacity of flotsam to entrain jetsam,in an initia... Particle segregation and mixing behavior play a crucial role in industrial processes.This study investigates the saturated jetsam fraction,which indicates the maximum capacity of flotsam to entrain jetsam,in an initially separated binary fluidized bed with particle size differences.According to the value of saturated jetsam fraction,three distinct regimes-segregation,mixing,and an intermediate regime-are identified.Moreover,intriguing relationships between the saturated jetsam fraction and superficial gas velocity are observed,exhibiting monotonic trends in both the segregation and mixing regimes,while a unique volcano-shaped curve in the intermediate regime.Additionally,a comprehensive entrainment model based on two-fluid model elucidates the observed phenomena,emphasizing the significance of mixing behavior in fluidized layer on the saturated jetsam fraction.This work offers potential insights for evaluating segregation in industrial applications. 展开更多
关键词 fluidized bed SEGREGATION BINARY BUBBLES ENTRAINMENT
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Rhodium complex-anchored and supramolecular polymer-grafted CdS nanoflower for enhanced photosynthesis of H_(2)O_(2) and photobiocatalytic C–H bond oxyfunctionalization
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作者 Hongwei Jia Xiaoyang Yue +7 位作者 Yuying Hou Fei Huang Cuiyao Cao Feifei Jia Guanhua Liu Xiaobing Zheng Yunting Liu Yanjun Jiang frontiers of chemical science and engineering SCIE EI CSCD 2024年第10期73-82,共10页
Unspecific peroxygenases exhibit high activity for the selective oxyfunctionalization of inert C(sp3)–H bonds using only H_(2)O_(2) as a clean oxidant,while also exhibiting sensitivity to H_(2)O_(2) concentration.CdS... Unspecific peroxygenases exhibit high activity for the selective oxyfunctionalization of inert C(sp3)–H bonds using only H_(2)O_(2) as a clean oxidant,while also exhibiting sensitivity to H_(2)O_(2) concentration.CdS-based semiconductors are promising for the photosynthesis of H_(2)O_(2) owing to their adequately negative potential for oxygen reduction reaction via a proton-coupled electron transfer process,however,they suffer from fast H_(2)O_(2) decomposition on the surface of pristine CdS.Therefore,[Cp*Rh(bpy)H_(2)O]2+,a highly selective proton-coupled electron transfer catalyst,was anchored onto a supramolecular polymer-grafted CdS nanoflower to construct an efficient integrated photocatalyst for generating H_(2)O_(2),mitigating the surface issue of pristine CdS,increasing light absorption,accelerating photonic carrier separation,and enhancing oxygen reduction reaction selectivity to H_(2)O_(2).This photocatalyst promoted the light driven H_(2)O_(2) generation rate up to 1345μmol·L^(-1)·g^(-1)·h^(-1),which was 2.4 times that of pristine CdS.The constructed heterojunction photocatalyst could supply H_(2)O_(2) in situ for nonspecific peroxygenases to catalyze the C–H oxyfunctionalization of ethylbenzene,achieving a yield of 81%and an ee value of 99%under optimum conditions.A wide range of substrates were converted to the corresponding chiral alcohols using this photo-enzyme catalytic system,achieving the corresponding chiral alcohols in good yield(51%–88%)and excellent enantioselectivity(90%–99%ee). 展开更多
关键词 cadmium sulfide unspecific peroxygenases photobiocatalysis hydrogen peroxide OXYFUNCTIONALIZATION
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Zeolites for the separation of ethylene,ethane,and ethyne
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作者 Binyu Wang Qiang Li +3 位作者 Haoyang Zhang Jia-Nan Zhang Qinhe Pan Wenfu Yan frontiers of chemical science and engineering SCIE EI CSCD 2024年第9期137-146,共10页
The cost-effective separation of ethylene(C_(2)H_(4)),ethyne(C_(2)H_(2)),and ethane(C_(2)H_(6))poses a significant challenge in the contemporary chemical industry.In contrast to the energy-intensive high-pressure cryo... The cost-effective separation of ethylene(C_(2)H_(4)),ethyne(C_(2)H_(2)),and ethane(C_(2)H_(6))poses a significant challenge in the contemporary chemical industry.In contrast to the energy-intensive high-pressure cryogenic distillation process,zeolite-based adsorptive separation offers a low-energy alternative.This review provides a concise overview of recent advancements in the adsorptive separation of C_(2)H_(4),C_(2)H_(2),and C_(2)H_(6)using zeolites or zeolite-based adsorbents.It commences with an examination of the industrial significance of these compounds and the associated separation challenges.Subsequently,it systematically examines the utilization of various types of zeolites with diverse cationic species in such separation processes.And then it explores how different zeolitic structures impact adsorption and separation capabilities,considering principles such as cation-πinteraction,π-complexation,and steric separation concerning C_(2)H_(4),C_(2)H_(2),and C_(2)H_(6)molecules.Furthermore,it discusses methods to enhance the separation performance of zeolites and zeolite-based adsorbents,encompassing structural design,modifications,and ion exchange processes.Finally,it summarizes current research trends and future directions,highlighting the potential application value of zeolitic materials in the field of C_(2)H_(4),C_(2)H_(2),and C_(2)H_(6)separation and offering recommendations for further investigation. 展开更多
关键词 zeolite ETHYLENE ETHANE cation-πinteraction π-complexation
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Self-supported copper-based gas diffusion electrodes improve the local CO_(2)concentration for efficient electrochemical CO_(2)reduction
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作者 Azeem Mustafa Bachirou Guene Lougou +6 位作者 Yong Shuai Zhijiang Wang Haseeb-ur-Rehman Samia Razzaq Wei Wang Ruming Pan Jiupeng Zhao frontiers of chemical science and engineering SCIE EI CSCD 2024年第3期51-62,共12页
Electrochemical CO_(2)reduction is a sustainable approach in green chemistry that enables the production of valuable chemicals and fuels while mitigating the environmental impact associated with CO_(2)emissions.Despit... Electrochemical CO_(2)reduction is a sustainable approach in green chemistry that enables the production of valuable chemicals and fuels while mitigating the environmental impact associated with CO_(2)emissions.Despite its several advantages,this technology suffers from an intrinsically low CO_(2)solubility in aqueous solutions,resulting in a lower local CO_(2)concentration near the electrode,which yields lower current densities and restricts product selectivity.Gas diffusion electrodes(GDEs),particularly those with tubular architectures,can solve these issues by increasing the local CO_(2)concentration and triple-phase interface,providing abundant electroactive sites to achieve superior reaction rates.In this study,robust and self-supported Cu flow-through gas diffusion electrodes(FTGDEs)were synthesized for efficient formate production via electrochemical CO_(2)reduction.They were further compared with traditional Cu electrodes,and it was found that higher local CO_(2)concentration due to improved mass transfer,the abundant surface area available for the generation of the triple-phase interface,and the porous structure of Cu FTGDEs enabled high formate Faradaic efficiency(76%)and current density(265 mA¸cm^(−2))at–0.9 V vs.reversible hydrogen electrode(RHE)in 0.5 mol·L^(−1)KHCO3.The combined phase inversion and calcination process of the Cu FTGDEs helped maintain a stable operation for several hours.The catalytic performance of the Cu FTGDEs was further investigated in a non-gas diffusion configuration to demonstrate the impact of local gas concentration on the activity and performance of electrochemical CO_(2)reduction.This study demonstrates the potential of flow-through gas-diffusion electrodes to enhance reaction kinetics for the highly efficient and selective reduction of CO_(2),offering promising applications in sustainable electrochemical processes. 展开更多
关键词 CO_(2)electroreduction flow-through delivery hollow fiber structure local concentration FORMATE
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Crystal facet-dependent CO_(2) cycloaddition to epoxides over ZnO catalysts
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作者 Yongjian Wei Ying Li +4 位作者 Yunfei Xu Yinghui Sun Tong Xu Haiou Liang Jie Bai frontiers of chemical science and engineering SCIE EI CSCD 2024年第5期49-59,共11页
With regard to green chemistry and sustainable development,the fixation of CO_(2) into epoxides to form cyclic carbonates is an attractive and promising pathway for CO_(2) utilization.Metal oxides,renowned as promisin... With regard to green chemistry and sustainable development,the fixation of CO_(2) into epoxides to form cyclic carbonates is an attractive and promising pathway for CO_(2) utilization.Metal oxides,renowned as promising eco-friendly catalysts for industrial production,are often undervalued in terms of their impact on the CO_(2)addition reaction.In this work,we successfully developed ZnO nanoplates with(002)surfaces and ZnO nanorods with(100)surfaces via morphology-oriented regulation to explore the effect of crystal faces on CO_(2) cycloaddition.The quantitative data obtained from electron paramagnetic resonance spectroscopy indicated that the concentration of oxygen vacancies on the ZnO nanoplate surfaces was more than twice that on the ZnO nanorod surfaces.Density functional theory calculations suggested that the(002)surfaces have lower adsorption energies for CO_(2) and epichlorohydrin than the(100)surfaces.As a result,the yield of cyclochloropropene carbonate on the ZnO nanoplates(64.7%)was much greater than that on the ZnO nanorods(42.3%).Further evaluation of the reused catalysts revealed that the decrease in the oxygen vacancy concentration was the primary factor contributing to the decrease in catalytic performance.Based on these findings,a possible catalytic mechanism for CO_(2) cycloaddition with epichlorohydrin was proposed.This work provides a new idea for the controllable preparation of high-performance ZnO catalysts for the synthesis of cyclic carbonates from CO_(2) and epoxides. 展开更多
关键词 carbon dioxide CYCLOADDITION zinc oxide crystal face oxygen vacancy
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Multifunctional carbon materials from rugose rose for energy storage and water purification
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作者 Peng-Hui Li Hui Zhou Wen-Juan Wu frontiers of chemical science and engineering SCIE EI CSCD 2024年第9期1-13,共13页
With the advancement of social process,the resource problem is becoming more prominent,biomass materials come into being,and it is becoming more and more important to explore and prepare efficient and multifunctional ... With the advancement of social process,the resource problem is becoming more prominent,biomass materials come into being,and it is becoming more and more important to explore and prepare efficient and multifunctional biomass materials to alleviate the problems of energy storage and water pollution.In this paper,nitrogen-doped hierarchical porous carbon materials(NRRC)were produced by one-step carbonization of withered rose as raw material and melamine as nitrogen source with KOH-activated porosification.The resulting nitrogen-doped porous carbon material had the most abundant pores and the best microspherical graded pore structure,with a specific surface area of up to 1393 m2·g^(-1),a pore volume of 0.68 cm3·g^(-1),and a nitrogen-doped content of 5.52%.Electrochemical tests showed that the maximum specific capacitance of NRRC in the three-electrode system was 346.4 F·g^(-1)(0.5 A·g^(-1)),which was combined with favorable capacitance retention performance and cycling stability.The NRRC//NRRC symmetric supercapacitors were further assembled,and the maximum energy density of a single device was 23.88 Wh·kg^(-1),which still maintains excellent capacitance retention and cyclic charging/discharging stability.For example,the capacitance retention rate was always close to 96.27%with almost negligible capacitance loss after 10000 consecutive charge/discharge cycles(current density:10 A·g^(-1)).Regardless of the three-electrode or two-electrode system,the super capacitive performance of NRRC porous carbon materials was comparable to the electrochemical performance of many reported biomass porous carbon materials,which showed better energy storage advantages and practical application potential.In addition,NRRC porous carbon materials had excellent water purification ability.The dye adsorption test confirmed that NRRC had a high adsorption capacity(491.47 mg·g^(-1))for methylene blue.This undoubtedly also showed a potential and promising avenue for high value-added utilization of this material. 展开更多
关键词 ROSE CARBON ADSORPTION electrode material electrochemical performance
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Insight into the selective separation of CO_(2)from biomass pyrolysis gas over metal-incorporated nitrogen-doped carbon materials:a first-principles study
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作者 Li Zhao Xinru Liu +5 位作者 Zihao Ye Bin Hu Haoyu Wang Ji Liu Bing Zhang Qiang Lu frontiers of chemical science and engineering SCIE EI CSCD 2024年第3期1-12,共12页
The composition of biomass pyrolysis gas is complex,and the selective separation of its components is crucial for its further utilization.Metal-incorporated nitrogen-doped materials exhibit enormous potential,whereas ... The composition of biomass pyrolysis gas is complex,and the selective separation of its components is crucial for its further utilization.Metal-incorporated nitrogen-doped materials exhibit enormous potential,whereas the relevant adsorption mechanism is still unclear.Herein,16 metal-incorporated nitrogen-doped carbon materials were designed based on the density functional theory calculation,and the adsorption mechanism of pyrolysis gas components H2,CO,CO_(2),CH_(4),and C2H6 was explored.The results indicate that metal-incorporated nitrogen-doped carbon materials generally have better adsorption effects on CO and CO_(2)than on H_(2),CH_(4),and C_(2)H_(6).Transition metal Mo-and alkaline earth metal Mg-and Ca-incorporated nitrogen-doped carbon materials show the potential to separate CO and CO_(2).The mixed adsorption results of CO_(2)and CO further indicate that when the CO_(2)ratio is significantly higher than that of CO,the saturated adsorption of CO_(2)will precede that of CO.Overall,the three metal-incorporated nitrogen-doped carbon materials can selectively separate CO_(2),and the alkaline earth metal Mg-incorporated nitrogen-doped carbon material has the best performance.This study provides theoretical guidance for the design of carbon capture materials and lays the foundation for the efficient utilization of biomass pyrolysis gas. 展开更多
关键词 CO_(2)capture biomass pyrolysis gas selective adsorption carbon materials FIRST-PRINCIPLES
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A tunable ionic covalent organic framework platform for efficient CO_(2) catalytic conversion
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作者 Ting Li Ji Xiong +5 位作者 Minghui Chen Quan Shi Xiangyu Li Yu Jiang Yaqing Feng Bao Zhang frontiers of chemical science and engineering SCIE EI CSCD 2024年第1期25-36,共12页
The cycloaddition reaction between epoxides and CO_(2) is an effective method to utilize CO_(2) resource.Covalent organic frameworks(COFs)provide a promising platform for the catalytic CO_(2) transformations on accoun... The cycloaddition reaction between epoxides and CO_(2) is an effective method to utilize CO_(2) resource.Covalent organic frameworks(COFs)provide a promising platform for the catalytic CO_(2) transformations on account of their remarkable chemical and physical properties.Herein,a family of novel vinylene-linked ionic COFs named TE-COFs(TTE-COF,TME-COF,TPE-COF,TBE-COF)has been facilely synthesized from N-ethyl2,4,6-trimethylpyridinium bromide and a series of triphenyl aromatic aldehydes involving different numbers of nitrogen atoms in the central aromatic ring.The resulting catalyst TTE-COF with excellent adsorption capacity(45.6 cm3·g^(-1),273 K)exhibited outstanding catalytic performance,remarkable recyclability and great substrate tolerance.Moreover,it was also observed that the introduction of nitrogen atom in the precursor led to a great improvement in the crystallinity and CO_(2) adsorption capacity of TE-COFs,thus resulting to a progressively improved catalytic performance.This work not only illustrated the influence of monomer nitrogen content on the crystallinity and CO_(2) adsorption capacity of TE-COFs but also provided a green heterogeneous candidate for catalyzing the cycloaddition between CO_(2) and epoxides,which shed a light on improving the catalytic performance of the CO_(2) cycloaddition reaction by designing the covalent organic frameworks structures. 展开更多
关键词 CO_(2)cycloaddition nreaction covalent organic frameworks cyclic carbonate vinylene-linked synergetic effects
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