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Effects of Catalysis and Separator Functionalization on High-Energy Lithium–Sulfur Batteries:A Complete Review 被引量:5
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作者 Muhammad Kashif Aslam Sidra Jamil +1 位作者 Shahid Hussain Maowen Xu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第3期333-355,共23页
Lithium–sulfur(Li-S)batteries have the advantages of high theoretical specific capacity(1675 mAh g^(−1)),rich sulfur resources,low production cost,and friendly environment,which makes it one of the most promising nex... Lithium–sulfur(Li-S)batteries have the advantages of high theoretical specific capacity(1675 mAh g^(−1)),rich sulfur resources,low production cost,and friendly environment,which makes it one of the most promising next-generation rechargeable energy storage devices.However,the“shuttle effect”of polysulfide results in the passivation of metal lithium anode,the decrease of battery capacity and coulombic efficiency,and the deterioration of cycle stability.To realize the commercialization of Li-S batteries,its serious“shuttle effect”needs to be suppress.The commercial separators are ineffective to suppress this effect because of its large pore size.Therefore,it is an effective strategy to modify the separator surface and introduce functional modified layer.In addition to the blocking strategy,the catalysis of polysulfide conversion reaction is also an important factor hindering the migration of polysulfides.In this review,the principles of separator modification,functionalization,and catalysis in Li-S batteries are reviewed.Furthermore,the research trend of separator functionalization and polysulfide catalysis in the future is prospected. 展开更多
关键词 catalysis Li-S batteries POLYSULFIDES separator functionalization shuttle effect
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CoB and BN composites enabling integrated adsorption/catalysis to polysulfides for inhibiting shuttle-effect in Li-S batteries 被引量:3
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作者 Tianli Wu Ting Yang +4 位作者 Jizong Zhang Xuewen Zheng Kunlin Liu Chengyang Wang Mingming Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第8期220-228,I0005,共10页
Lithium-sulfur(Li-S)batteries are hampered by the infamous shuttle effect and slow redox kinetics,resulting in rapid capacity decay.Herein,a bifunctional catalysis CoB/BN@rGO with integrated structure and synergy effe... Lithium-sulfur(Li-S)batteries are hampered by the infamous shuttle effect and slow redox kinetics,resulting in rapid capacity decay.Herein,a bifunctional catalysis CoB/BN@rGO with integrated structure and synergy effect between adsorption and catalysis is proposed to solve the above problems.The integrated CoB and BN are simultaneously and uniformly introduced on the rGO substrate through a one-step calcination strategy,applied to modify the cathode side of PP separator.The transition metal borides can catalyze the conversion of lithium polysulfides(Li_(2)Sn,n≥4),whereas the bond of B-S is too weak to absorb LPS.Thus BN introduced can effectively restrict the diffusion of polysulfides via strong chemisorption with LiSnLi+…N,while the rGO substrate ensures smooth electron transfer for redox reaction.Therefore,through the integrated adsorption/catalysis,the shuttle effect is suppressed,the kinetics of redox reaction is enhanced,and the capacity decay is reduced.Using CoB/BN@rGO modified PP separator,the Li-S batteries with high initial capacity(1450 mAh g^(-1)at 0.35 mA cm^(-2))and long-cycle stability(700 cycles at 1.74 mA cm^(-2)with a decay rate of 0.032%per cycle)are achieved.This work provides a novel insight for the preparation of bifunctional catalysis with integrated structure for long-life Li-S batteries. 展开更多
关键词 Integrated structure Synergy effect Bifunctional catalysis SEPARATOR Li-S batteries
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Polysulfides adsorption and catalysis dual-sites on metal-doped molybdenum oxide nanoclusters for Li-S batteries with wide operating temperature
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作者 Jieshuangyang Chen Jie Lei +5 位作者 Jinwei Zhou Xuanfeng Chen Rongyu Deng Mingzhi Qian Ya Chen Feixiang Wu 《Nano Research》 SCIE EI CSCD 2024年第11期9651-9661,共11页
The development of electrocatalysts with high catalytic activity is conducive to enhancing polysulfides adsorption and reducing activation energy of polysulfides conversion, which can effectively reduce polysulfide sh... The development of electrocatalysts with high catalytic activity is conducive to enhancing polysulfides adsorption and reducing activation energy of polysulfides conversion, which can effectively reduce polysulfide shuttling in Li-S batteries. Herein, a novel catalyst NiCo-MoO x /rGO (rGO = reduced graphene oxides) with ultra-nanometer scale and high dispersity is derived from the Anderson-type polyoxometalate precursors, which are electrostatically assembled on the multilayer rGO. The catalyst material possesses dual active sites, in which Ni-doped MoO x exhibits strong polysulfide anchoring ability, while Co-doped MoO x facilitates the polysulfides conversion reaction kinetics, thus breaking the Sabatier effect in the conventional electrocatalytic process. In addition, the prepared NiCo-MoO x /rGO modified PP separator (NiCo-MoO x /rGO@PP) can serve as a physical barrier to further inhibit the polysulfide shuttling effect and realize the rapid Li+ migration. The results demonstrate that Li-S coin cell with NiCo-MoO x /rGO@PP separator shows excellent cycling performance with the discharge capacity of 680 mAh·g^(−1) after 600 cycles at 1 C and the capacity fading of 0.064% per cycle. The rate performance is also impressive with the remained capacity of 640 mAh·g^(−1) after 200 cycles even at 4 C. When the sulfur loading is 4.0 mg·cm^(−2) and electrolyte volume/sulfur mass ratio (E/S) ratio is 6.0 μL·mg^(−1), a specific capacity of 830 mAh·g^(−1) is achieved after 200 cycles with a capacity decay of 0.049% per cycle. More importantly, the cell with NiCo-MoO x /rGO@PP separator exhibits cycling performance under wide operating temperature with the reversible capacities of 518, 715, and 915 mAh·g^(−1) after 100 cycles at −20, 0, and 60 °C, respectively. This study provides a new design approach of highly efficient catalysts for sulfur conversion reaction in Li-S batteries. 展开更多
关键词 lithium-sulfur batteries doped molybdenum oxide separator modification adsorption and catalysis dual-sites wide temperature
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Chiral covalent organic frameworks for asymmetric catalysis and chiral separation 被引量:4
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作者 Liu,Guofeng Sheng,Jianhui Zhao,Yanli 《Science China Chemistry》 SCIE EI CAS CSCD 2017年第8期1015-1022,共8页
Covalent organic frameworks(COFs), covalently assembled from the condensation reactions of organic building blocks, are a fascinating class of functional porous materials with two-or three-dimensional crystalline orga... Covalent organic frameworks(COFs), covalently assembled from the condensation reactions of organic building blocks, are a fascinating class of functional porous materials with two-or three-dimensional crystalline organic structures. Generally, it is preferable to use symmetric and rigid building blocks to construct highly crystalline COFs with desired topology. On the other hand, the incorporation of chiral functional moieties in the building blocks would open up new applications such as asymmetric catalysis and chiral separation. This mini review highlights the principle strategies in the design and synthesis of chiral COFs. The interesting and potential applications of these chiral COFs for asymmetric catalysis and chiral separation are also summarized.This mini review aims to provide an up-to-date advancement of chiral COFs for asymmetric catalysis and chiral separation. 展开更多
关键词 asymmetric catalysis building blocks chiral separation covalent organic frameworks porous materials
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Bi-functional particles for integrated thermo-chemical processes:Catalysis and beyond 被引量:1
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作者 Hanke Li Chengxiong Dang +4 位作者 Guangxing Yang Yonghai Cao Hongjuan Wang Feng Peng Hao Yu 《Particuology》 SCIE EI CAS CSCD 2021年第3期10-32,共23页
Particulate materials possessing dual functionalities have received tremendous investigations in many fields,owing to their superiority over mono-functional counterparts and their potential for process integration and... Particulate materials possessing dual functionalities have received tremendous investigations in many fields,owing to their superiority over mono-functional counterparts and their potential for process integration and intensification.This review focuses on bi-functional catalytic particles which also serve as sorbents/adsorbents or heat suppliers in the scheme of various thermo-chemical processes,enabling inherent separation or energy conservation within single-step operation.Bi-functional particles applied for integration of reaction and separation including sorption-enhanced hydrogen production and integrated capture and catalytic conversion processes are reviewed in detail,providing insights into material design and key performance indicators.On the other hand,bi-functional particles applied for integration of reaction and non-thermal radiation heating,including electrothermal and photothermal assisted heterogeneously catalyzed reactions,are also reviewed,with emphasis on the material property and energy efficiency improvement.These bi-functional particles show broad adaptability and feasibility in various reactions operated in integrated and intensified schemes,affording huge potentials for further improving productivity and efficiency in thermo-chemical processes. 展开更多
关键词 Bi-functional particles Thermo-chemical processes catalysis separation Energy conservation Process integration and intensification
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Bidirectional catalysis of Co_(0.4)Ni_(1.6)P for Li_(2)S_(1-2) deposition/decomposition reactions in Li-S batteries 被引量:3
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作者 Luluan Feng Shengping Wang 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第8期2267-2273,共7页
To improve the electrochemical activity of S electrodes in Li-S batteries,the synergistic electrocatalysis mechanism of Co_(0.4)Ni_(1.6)P with Ni and Co bimetal interactions is clarified.The alternating crystal struct... To improve the electrochemical activity of S electrodes in Li-S batteries,the synergistic electrocatalysis mechanism of Co_(0.4)Ni_(1.6)P with Ni and Co bimetal interactions is clarified.The alternating crystal structure of Co and Ni regulates the adsorption and decomposition energy of Co_(0.4)Ni_(1.6)P to polysulfides and has the bidirectional catalysis for the Li_(2)S_(1-2)deposition/decomposition process.Co_(0.4)Ni_(1.6)P can promote the breaking of the S-S bond of Li_(2)S_(4) and decrease the decomposition energy barrier of Li_(2)S.This regulation accelerates the discharge/charge reaction between S,polysulfides,and Li_(2)S and improves the kinetics of the S electrodes.The 1st,100^(th),and 200^(th) discharge capacity densities at 0.1 mA cm^(-2) of the S electrodes with a high sulfur loading were 1,405,987.2,and 828.4 m Ah gS^(-1),respectively.The bidirectional catalytic mechanism is a novel idea for improving the electrochemical performance of Li-S batteries. 展开更多
关键词 bidirectional catalysis double active sites S electrode SEPARATOR Li-S batteries
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Porous framework materials for energy&environment relevant applications:A systematic review 被引量:1
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作者 Yutao Liu Liyu Chen +16 位作者 Lifeng Yang Tianhao Lan Hui Wang Chenghong Hu Xue Han Qixing Liu Jianfa Chen Zeming Feng Xili Cui Qianrong Fang Hailong Wang Libo Li Yingwei Li Huabin Xing Sihai Yang Dan Zhao Jinping Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第2期217-310,共94页
Carbon peaking and carbon neutralization trigger a technical revolution in energy&environment related fields.Development of new technologies for green energy production and storage,industrial energy saving and eff... Carbon peaking and carbon neutralization trigger a technical revolution in energy&environment related fields.Development of new technologies for green energy production and storage,industrial energy saving and efficiency reinforcement,carbon capture,and pollutant gas treatment is in highly imperious demand.The emerging porous framework materials such as metal–organic frameworks(MOFs),covalent organic frameworks(COFs)and hydrogen-bonded organic frameworks(HOFs),owing to the permanent porosity,tremendous specific surface area,designable structure and customizable functionality,have shown great potential in major energy-consuming industrial processes,including sustainable energy gas catalytic conversion,energy-efficient industrial gas separation and storage.Herein,this manuscript presents a systematic review of porous framework materials for global and comprehensive energy&environment related applications,from a macroscopic and application perspective. 展开更多
关键词 Porous framework materials catalysis separation Gas storage Carbon neutrality
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酸催化己糖脱水合成5-羟甲基糠醛:反应、分离和过程耦合
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作者 刘苗 焦莹莹 +6 位作者 丁玲 李城城 何颖 孙亮亮 郝青青 陈汇勇 罗群兴 《化工进展》 EI CAS CSCD 北大核心 2024年第5期2526-2543,共18页
5-羟甲基糠醛(HMF)是生物质转化为化学品、燃料和聚酯材料的重要平台化合物之一。理性设计高效催化剂、优化催化反应过程、开发新型分离以及反应-分离单元耦合技术能够强化HMF生产综合效能,还可以简化工艺流程、降低碳排放和能耗。本文... 5-羟甲基糠醛(HMF)是生物质转化为化学品、燃料和聚酯材料的重要平台化合物之一。理性设计高效催化剂、优化催化反应过程、开发新型分离以及反应-分离单元耦合技术能够强化HMF生产综合效能,还可以简化工艺流程、降低碳排放和能耗。本文立足于酸催化己糖脱水合成HMF过程中反应和分离的关键科学问题,从催化剂活性位“接力式”设计、催化反应串联耦合、表面亲疏水性调控、反应溶剂匹配、固-液吸附材料、吸附机制和构-效关系、反应-分离过程强化等方面出发,系统综述酸催化己糖脱水合成HMF过程中的反应、分离和过程耦合相关研究进展,为生物质资源高效转化利用过程中催化和分离系统的综合设计提供参考与指导。 展开更多
关键词 生物质 5-羟甲基糠醛 催化 分离 过程强化
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中长链甘油三酯的酶法制备研究进展
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作者 赖运栋 张逸 +3 位作者 谢礼文 郑明明 张羽飞 黎冬明 《中国油料作物学报》 CAS CSCD 北大核心 2024年第4期719-727,共9页
中长链甘油三酯(medium and long-chain triacylglycerols,MLCT)是一类具有特殊理化性质和营养功能的结构脂质。随着MLCT在食品、医药、保健品、母乳脂等行业中的需求不断增长,酶法制备MLCT的研究也逐渐成为热点。文章对MLCT的酶合成策... 中长链甘油三酯(medium and long-chain triacylglycerols,MLCT)是一类具有特殊理化性质和营养功能的结构脂质。随着MLCT在食品、医药、保健品、母乳脂等行业中的需求不断增长,酶法制备MLCT的研究也逐渐成为热点。文章对MLCT的酶合成策略,包括对合成途径、脂肪酶种类、催化反应体系和产品分离纯化等方面进行了总结、分析和探讨,以期为MLCT的酶法制备的研究与应用提供参考。 展开更多
关键词 MLCT 脂肪酶 催化 反应体系 分离纯化
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MOFs基多孔液体的制备及CO_(2)吸附分离应用
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作者 靳归 黄琳 +2 位作者 郭东方 王娟 王焕君 《精细化工》 EI CAS CSCD 北大核心 2024年第1期23-37,共15页
多孔液体(PLs)是一种结合了多孔固体材料永久孔隙和液体流动性的新型液体材料,在气体吸附和分离、催化等应用领域中展示出巨大的潜力。金属框架材料(MOFs)因其高的比表面积、热和化学稳定性、独特的结构以及制备简单的特点有望成为构筑... 多孔液体(PLs)是一种结合了多孔固体材料永久孔隙和液体流动性的新型液体材料,在气体吸附和分离、催化等应用领域中展示出巨大的潜力。金属框架材料(MOFs)因其高的比表面积、热和化学稳定性、独特的结构以及制备简单的特点有望成为构筑PLs多孔宿主的最佳候选材料之一。近些年来,基于MOFs(ZIF-8、ZIF-67、Ui O-66等)基多孔液体相关研究被陆续报道。首先,该文介绍了多孔液体的分类;其次,总结了近些年来MOFs基多孔液体的制备以及应用;最后,对MOFs基多孔液体的制备存在的挑战与未来的发展方向进行了总结与展望。 展开更多
关键词 多孔液体 气体吸附 分离 催化 二氧化碳
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6N电子级氘气的制备与纯化技术研究
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作者 孟祥军 花莹曦 +5 位作者 张长金 张弛 杨林睿 杨若昔 刘鉴漪 许春建 《化工学报》 EI CSCD 北大核心 2024年第1期377-390,共14页
电子级氘气在集成电路制造的高温退火工艺中起到关键作用,高端制程工艺要求其纯度高达6N。提出了完整的6N氘气电解制备与纯化技术路线,包括:(1)设计出高效FeNi@ClBC OER催化剂,性能显著优于商用催化剂,提高了催化效率并降低整体能耗;(2... 电子级氘气在集成电路制造的高温退火工艺中起到关键作用,高端制程工艺要求其纯度高达6N。提出了完整的6N氘气电解制备与纯化技术路线,包括:(1)设计出高效FeNi@ClBC OER催化剂,性能显著优于商用催化剂,提高了催化效率并降低整体能耗;(2)提出了电解阳极端氧气气提脱除重水中氮气等杂质的工艺流程,重水杂质的减少降低了氘气纯化的难度;(3)提出了深度脱氧、脱水工艺流程,筛选出最佳脱氧催化剂和脱水吸附分子筛并对工艺参数进行了优化,实现产品中杂质氧和水含量(体积分数)分别低于1×10^(-8)和1.65×10^(-7)的目标。实验得到的超高纯氘气产品指标达到了6N,满足先进制程集成电路制造需求,为低成本生产超高纯氘气提供了参考。 展开更多
关键词 电解 制备 催化 吸附 纯化 分离
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Design and Fabrication of Ceramic Catalytic Membrane Reactors for Green Chemical Engineering Applications 被引量:5
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作者 Guangru Zhang Wanqin Jin Nanping Xu 《Engineering》 SCIE EI 2018年第6期848-860,共13页
Catalytic membrane reactors(CMRs),which synergistically carry out separations and reactions,are expected to become a green and sustainable technology in chemical engineering.The use of ceramic membranes in CMRs is bei... Catalytic membrane reactors(CMRs),which synergistically carry out separations and reactions,are expected to become a green and sustainable technology in chemical engineering.The use of ceramic membranes in CMRs is being widely considered because it permits reactions and separations to be carried out under harsh conditions in terms of both temperature and the chemical environment.This article presents the two most important types of CMRs:those based on dense mixed-conducting membranes for gas separation,and those based on porous ceramic membranes for heterogeneous catalytic processes.New developments in and innovative uses of both types of CMRs over the last decade are presented,along with an overview of our recent work in this field.Membrane reactor design,fabrication,and applications related to energy and environmental areas are highlighted.First,the configuration of membranes and membrane reactors are introduced for each of type of membrane reactor.Next,taking typical catalytic reactions as model systems,the design and optimization of CMRs are illustrated.Finally,challenges and difficulties in the process of industrializing the two types of CMRs are addressed,and a view of the future is outlined. 展开更多
关键词 DENSE CERAMIC MEMBRANE Porous CERAMIC MEMBRANE CATALYTIC MEMBRANE REACTOR Gas separation Heterogeneous catalysis
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反应精馏制备乙酸乙酯
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作者 庞心怡 李建 +3 位作者 赵爱娟 张子豪 张子涵 冯佳琪 《广州化工》 CAS 2024年第10期26-27,30,共3页
乙酸乙酯作为工业上重要的溶剂,被广泛用于人类生产生活中。反应精馏技术是制备乙酸乙酯的重要技术,在化学工业中发挥着重要作用。相对于传统精馏的过程,反应精馏可以很好地降低生产成本并提高反应的效率。本文依据安全、经济和可行性原... 乙酸乙酯作为工业上重要的溶剂,被广泛用于人类生产生活中。反应精馏技术是制备乙酸乙酯的重要技术,在化学工业中发挥着重要作用。相对于传统精馏的过程,反应精馏可以很好地降低生产成本并提高反应的效率。本文依据安全、经济和可行性原则,立足于反应精馏制备乙酸乙酯的新工艺,总结了乙酸乙酯的性质、反应精馏的研究历程,重点分析了反应精馏耦合的其他新工艺技术的研究现状,重点讲解了酶反应精馏等新工艺,并对其未来发展进行了展望。 展开更多
关键词 乙酸乙酯 分离 催化(作用) 精馏 化学过程
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苏沃雷生的合成研究进展
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作者 韩冰冰 侯建 +1 位作者 邱迅 陈再新 《合成化学》 CAS 2024年第7期673-684,共12页
苏沃雷生(Suvorexant)由默沙东公司首研上市,是首个被批准上市的食欲素受体拮抗剂,临床上用于治疗以睡眠开始和/或睡眠维持困难为特征的失眠。本文对苏沃雷生原料药的合成路线进行了分析、总结和概括,并将合成路线分成两个大类进行总结... 苏沃雷生(Suvorexant)由默沙东公司首研上市,是首个被批准上市的食欲素受体拮抗剂,临床上用于治疗以睡眠开始和/或睡眠维持困难为特征的失眠。本文对苏沃雷生原料药的合成路线进行了分析、总结和概括,并将合成路线分成两个大类进行总结。第一类为片段拼接,在片段拼接合成方法中,关键的手性中间体有拆分的方法和手性起始原料法。手性起始原料法因不需要拆分,收率高,具有较好的产业化价值。第二类为顺序合成,其中钌催化具有较高收率,而酶催化避免了使用卤代溶剂和重金属,符合绿色化学理念,在未来发展中更具优势。本文总结的相关路线内容为苏沃雷生的产业化研究提供参考。 展开更多
关键词 苏沃雷生 食欲素受体拮抗剂 合成 手性拆分 钌催化 酶催化
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类芬顿催化膜的制备及其处理有机废水的研究进展
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作者 黄春燕 燕思吟 +1 位作者 赖芳 葛圆圆 《石油炼制与化工》 CAS CSCD 北大核心 2024年第2期91-100,共10页
类芬顿催化膜在处理废水中污染物方面具有明显的优势,广泛应用于去除染料、油污、新型污染物等领域。阐述了常见的类芬顿催化膜类型(包括过渡金属基、炭基、复合型和其他新型催化膜等)及制备方法,并分析了类芬顿催化膜体系在处理水中有... 类芬顿催化膜在处理废水中污染物方面具有明显的优势,广泛应用于去除染料、油污、新型污染物等领域。阐述了常见的类芬顿催化膜类型(包括过渡金属基、炭基、复合型和其他新型催化膜等)及制备方法,并分析了类芬顿催化膜体系在处理水中有机污染物的膜过滤和氧化降解机理,综述了类芬顿催化膜在典型有机废水中的应用现状,提出了类芬顿催化膜水处理技术面临的挑战,有助于促进类芬顿催化膜在实际废水处理中的发展和应用。 展开更多
关键词 类芬顿氧化 膜分离 膜催化 有机废水
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高硅LTA型分子筛的合成及应用研究进展
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作者 刘汉邦 郝文月 +3 位作者 郭俊辉 刘昶 王凤来 彭绍忠 《应用化学》 CAS CSCD 北大核心 2024年第9期1248-1258,共11页
LTA(Linde type A)结构类型的分子筛是早期通过人工合成得到的沸石分子筛之一。目前,工业化的LTA型分子筛即A型分子筛的硅铝比较低,尽管它在吸附和分离等过程中被大量应用,但较差的酸催化活性和水热稳定性限制了其进一步的应用。高硅LT... LTA(Linde type A)结构类型的分子筛是早期通过人工合成得到的沸石分子筛之一。目前,工业化的LTA型分子筛即A型分子筛的硅铝比较低,尽管它在吸附和分离等过程中被大量应用,但较差的酸催化活性和水热稳定性限制了其进一步的应用。高硅LTA型分子筛具有比低硅的A型分子筛更好的热/水热稳定性,且在吸附分离以及催化等领域具有独特的应用潜力。本文综述并讨论了自1966年以来高硅LTA型分子筛的合成体系,重点集中在近70年来的发展,包括无机体系和有机体系,针对不同的合成体系以及硅铝比,阐述了其合成机理并对合成方法的优缺点进行了评价。讨论了高硅LTA型分子筛在吸附分离以及催化领域的应用与研究进展,对未来LTA型分子筛的发展与应用进行了展望,并指出深入掌握晶化机理,开发简单的合成体系,廉价的结构导向剂将是高硅LTA型分子筛研究的重点。 展开更多
关键词 LTA分子筛 高硅 结构导向剂 吸附分离 催化
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蔗渣水解液酸催化制备糠醛及其萃取分离
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作者 何孜孜 李军荣 +2 位作者 李芳彬 何北海 钱丽颖 《精细化工》 EI CAS CSCD 北大核心 2024年第5期1067-1075,共9页
首先,蔗渣在高温下通过酸性水解制备了水解液和水解渣;然后,水解液经深度酸解制备了糠醛,并以有机溶剂萃取分离了水相中的糠醛;水解渣经硫酸盐蒸煮制备了浆料纤维。采用FTIR、XRD、SEM、TG对蔗渣及水解渣进行了表征,利用UV-Vis吸收光谱... 首先,蔗渣在高温下通过酸性水解制备了水解液和水解渣;然后,水解液经深度酸解制备了糠醛,并以有机溶剂萃取分离了水相中的糠醛;水解渣经硫酸盐蒸煮制备了浆料纤维。采用FTIR、XRD、SEM、TG对蔗渣及水解渣进行了表征,利用UV-Vis吸收光谱对水解液中的木糖及深度酸解液中的糠醛进行了定量检测。对蔗渣预水解条件、糠醛的有机溶剂萃取条件进行了考察。结果表明,在反应温度160℃、液固比(mL∶g)为6∶1、浓硫酸用量为0.176%(以绝干蔗渣质量计,下同)的条件下,预水解反应3 h后,水解液中木糖质量浓度最高(41.72 g/L);水解液在170℃下深度酸解90 min,深度酸解液中糠醛质量浓度最高可达15.91 g/L,糠醛收率最高为59.60%。以V(1,2-二氯乙烷)∶V(正丁醇)=9∶1的混合溶剂萃取深度酸解液中糠醛(有机相与水相体积比为2∶1),糠醛分配系数最高为7.62,糠醛的萃取率可达93.53%。浆料中α-纤维素质量分数高达93.41%,纤维长径比为29.9,细小纤维占比34.7%。 展开更多
关键词 蔗渣 糠醛 预水解 深度酸解 有机溶剂萃取 催化与分离提纯技术
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Atomically Dispersed Iron Active Sites Promoting Reversible Redox Kinetics and Suppressing Shuttle Effect in Aluminum-Sulfur Batteries
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作者 Fei Wang Min Jiang +6 位作者 Tianshuo Zhao Pengyu Meng Jianmin Ren Zhaohui Yang Jiao Zhang Chaopeng Fu Baode Sun 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第10期248-259,共12页
Rechargeable aluminum-sulfur(Al-S)batteries have been considered as a highly potential energy storage system owing to the high theoretical capacity,good safety,abundant natural reserves,and low cost of Al and S.Howeve... Rechargeable aluminum-sulfur(Al-S)batteries have been considered as a highly potential energy storage system owing to the high theoretical capacity,good safety,abundant natural reserves,and low cost of Al and S.However,the research progress of Al-S batteries is limited by the slow kinetics and shuttle effect of soluble polysulfides intermediates.Herein,an interconnected free-standing interlayer of iron sin-gle atoms supported on porous nitrogen-doped carbon nanofibers(FeSAs-NCF)on the separator is developed and used as both catalyst and chemical barrier for Al-S batteries.The atomically dispersed iron active sites(Fe-N_(4))are clearly identified by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and X-ray absorption near-edge structure.The Al-S battery with the FeSAs-NCF shows an improved specific capacity of 780 mAh g^(−1)and enhanced cycle stability.As evidenced by experimental and theoretical results,the atomically dispersed iron active centers on the separator can chemically adsorb the polysulfides and accelerate reaction kinetics to inhibit the shuttle effect and promote the reversible conversion between aluminum polysulfides,thus improving the electrochemical performance of the Al-S battery.This work provides a new way that can not only promote the conversion of aluminum sulfides but also suppress the shuttle effect in Al-S batteries. 展开更多
关键词 Fe single atom Aluminum-sulfur battery catalysis Shuttle effect Separator modification
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无碱条件下Ru/MgO催化5-羟甲基糠醛氧化并制备高纯度2,5-呋喃二甲酸
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作者 楚国宁 王赛 +2 位作者 马骥 李菁 张爽 《化工科技》 CAS 2024年第4期55-61,共7页
采用煅烧法制备载体MgO,再采用浸渍-还原法制备Ru/MgO催化剂。对催化剂进行表征分析,结果表明,MgO负载Ru后比表面积与碱量增加,Ru作为催化剂活性中心,将Ru/MgO催化剂用于无碱条件下5-羟甲基糠醛(HMF)的选择性氧化,催化活性显著提高。Mg... 采用煅烧法制备载体MgO,再采用浸渍-还原法制备Ru/MgO催化剂。对催化剂进行表征分析,结果表明,MgO负载Ru后比表面积与碱量增加,Ru作为催化剂活性中心,将Ru/MgO催化剂用于无碱条件下5-羟甲基糠醛(HMF)的选择性氧化,催化活性显著提高。MgO在负载Ru后,转换频率(TOF)由2.82×10^(-4) h^(-1)提高至5.98×10^(-1) h^(-1)。Ru/MgO催化剂在最佳反应条件下,HMF转化率为100%,2,5-呋喃二甲酸(FDCA)的产率为95.7%,且在循环使用3次后仍能保持较高的活性,活性组分Ru不易浸出,MgO仅有少量溶解。并采用半制备液相色谱实现产物的绿色分离,最终得到纯度大于99%的FDCA粉末,避免了向体系加入浓盐酸分离出FDCA。该制备方法为无碱体系催化HMF高效合成FDCA提供参考。 展开更多
关键词 Ru纳米粒子 MGO 5-羟甲基糠醛 无碱催化 产物分离 2 5-呋喃二甲酸
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Selective sulfur conversion with surface engineering of electrocatalysts in a lithium-sulfur battery 被引量:2
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作者 Yuejin Zhu Yinze Zuo +4 位作者 Xuechao Jiao Revanasiddappa Manjunatha Ejikeme Raphael Ezeigwe Wei Yan Jiujun Zhang 《Carbon Energy》 SCIE CSCD 2023年第2期72-84,共13页
The sluggish kinetics of multiphase sulfur conversion with homogeneous and heterogeneous electrochemical processes,causing the“shuttle effect”of soluble polysulfide species(PSs),is the challenges in terms of lithium... The sluggish kinetics of multiphase sulfur conversion with homogeneous and heterogeneous electrochemical processes,causing the“shuttle effect”of soluble polysulfide species(PSs),is the challenges in terms of lithium-sulfur batteries(LSBs).In this paper,a Mn_(3)O_(4-x) catalyst,which has much higher activity for heterogeneous reactions than for homogeneous reactions(namely,preferentialactivity catalysts),is designed by surface engineering with rational oxygen vacancies.Due to the rational design of the electronic structure,the Mn_(3)O_(4-x) catalyst prefers to accelerate the conversion of Li2S4 into Li_(2)S_(2)/Li_(2)S and optimize Li_(2)S deposition,reducing the accumulation of PSs and thus suppressing the“shuttle effect.”Both density functional theory calculations and in situ X-ray diffraction measurements are used to probe the catalytic mechanism and identify the reaction intermediates of MnS and Li_(y)Mn_(z)O_(4-x) for fundamental understanding.The cell with Mn_(3)O_(4-x) delivers an ultralow attenuation rate of 0.028% per cycle over 2000 cycles at 2.5 C.Even with sulfur loadings of 4.93 and 7.10mg cm^(-2) in a lean electrolyte(8.4μL mg s^(-1)),the cell still shows an initial areal capacity of 7.3mAh cm^(-2).This study may provide a new way to develop preferential-activity heterogeneous-reaction catalysts to suppress the“shuttle effect”of the soluble PSs generated during the redox process of LSBs. 展开更多
关键词 electrochemical kinetics heterogeneous catalysis lithium-sulfur batteries Mn3O4-x-catalyzed separator surface engineering
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