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OSDA-free synthesis of FeZSM-22 zeolite from natural minerals for n-octane hydroisomerization
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作者 Tiesen Li Ting Chen +5 位作者 Yinghui Ye Peng Dong TinghaiWang Qingyan Cui Chan Wang Yuanyuan Yue 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期51-59,共9页
A seed-directed approach to synthesizing Fe ZSM-22 zeolite without organic structure directing agent(OSDA)was developed by using Fe-rich diatomite as all aluminum and iron sources.The Fe ZSM-22zeolite with optimal cry... A seed-directed approach to synthesizing Fe ZSM-22 zeolite without organic structure directing agent(OSDA)was developed by using Fe-rich diatomite as all aluminum and iron sources.The Fe ZSM-22zeolite with optimal crystallinity and purity can be obtained by systematically adjusting feed composition and synthesis conditions.Characterizations show that Fe ZSM-22 zeolite synthesized with OSDA-free owns high crystallinity,obvious thin needle-shaped morphology and high Bronsted/Lewis acid ratio.Significantly,when used for n-octane hydroisomerization reaction,its derived catalyst exhibits the best catalytic performance reflected by the highest selectivity to C_(8)isomers compared to the two reference catalysts prepared based on a Fe-containing and a Fe-free ZSM-22 synthesized through an OSDA-directed route from natural diatomite and conventional chemicals,respectively.This work provides an alternative route to sustainably synthesizing heteroatomic zeolites with high performance. 展开更多
关键词 FeZSM-22 zeolite OSDA-free synthesis Natural minerals n-octane hydroisomerization
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Facile synthesis of hierarchical NaX zeolite from natural kaolinite for efficient Knoevenagel condensation
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作者 Wen Xiao Peng Dong +6 位作者 Chan Wang Jingdong Xu Tiesen Li Haibo Zhu Tinghai Wang Renwei Xu Yuanyuan Yue 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期75-84,共10页
Zeolite catalysts have found extensive applications in the synthesis of various fine chemicals.However,the micropores of zeolites impose diffusion limitations on bulky molecules,greatly reducing the catalytic efficien... Zeolite catalysts have found extensive applications in the synthesis of various fine chemicals.However,the micropores of zeolites impose diffusion limitations on bulky molecules,greatly reducing the catalytic efficiency.Herein,we explore an economic and environmentally friendly method for synthesizing hierarchical NaX zeolite that exhibits improved catalytic performance in the Knoevenagel condensation reaction for producing the useful fine chemical 2-cyano-3-phenylacrylate.The synthesis was achieved via a low-temperature activation of kaolinite and subsequent in-situ transformation strategy without any template or seed.Systematic characterizations reveal that the synthesized NaX zeolite has both intercrystalline and intra-crystalline mesopores,smaller crystal size,and larger external specific surface area compared to commercial NaX zeolite.Detailed mechanism investigations show that the inter-crystalline mesopores are generated by stacking smaller crystals formed from in-situ crystallization of the depolymerized kaolinite,and the intra-crystalline mesopores are inherited from the pores in the depolymerized kaolinite.This synthesis strategy provides an energy-saving and effective way to construct hierarchical zeolites,which may gain wide applications in fine chemical manufacturing. 展开更多
关键词 Hierarchical NaX zeolite Template-free synthesis Natural kaolinite Knoevenagel condensation
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Advances in particulate matter filtration:Materials,performance,and application 被引量:1
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作者 Xuzheng Ji Jianying Huang +5 位作者 Lin Teng Shuhui Li Xiao Li Weilong Cai Zhong Chen Yuekun Lai 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第3期673-697,共25页
Air-borne pollutants in particulate matter(PM)form,produced either physically during industrial processes or certain biological routes,have posed a great threat to human health.Particularly during the current COVID-19... Air-borne pollutants in particulate matter(PM)form,produced either physically during industrial processes or certain biological routes,have posed a great threat to human health.Particularly during the current COVID-19 pandemic,effective filtration of the virus is an urgent matter worldwide.In this review,we first introduce some fundamentals about PM,including its source and classification,filtration mechanisms,and evaluation parameters.Advanced filtration materials and their functions are then summarized,among which polymers and MOFs are discussed in detail together with their antibacterial performance.The discussion on the application is divided into end-of-pipe treatment and source control.Finally,we conclude this review with our prospective view on future research in this area. 展开更多
关键词 Air filtration PM capture End-of-pipe treatment Source control COVID-19
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Numerical study of inhibition mechanism of high-pressure hydrogen leakage self-ignition with the addition of ammonia 被引量:1
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作者 Lin Teng Xi-Gui Li +7 位作者 Zhi-Wei Shan Wei-Dong Li Xin Huang Peng-Bo Yin Yong-Zhen Liu Jiang Bian Yu Luo Li-Long Jiang 《Petroleum Science》 SCIE EI CSCD 2023年第5期3184-3193,共10页
Hydrogen and ammonia have attracted increasing attention as carbon-free fuels.Ammonia is considered to be an effective energy storage and hydrogen storage medium.However,a small amount of unremoved NH3 is still presen... Hydrogen and ammonia have attracted increasing attention as carbon-free fuels.Ammonia is considered to be an effective energy storage and hydrogen storage medium.However,a small amount of unremoved NH3 is still present in the product during the decomposition of ammonia to produce hydrogen.Therefore,it is very essential to investigate the self-ignition of hydrogen-ammonia mixtures in order to accommodate the various scenarios of hydrogen energy applications.In this paper,the effect of NH3 addition on the self-ignition of high-pressure hydrogen release is numerically investigated.The RNG k-εturbulence model,EDC combustion model,and 213-step detailed NH_(3)/H_(2) combustion mechanism are used.CHEMKIN-Pro programs for zero-dimensional homogeneous and constant volume adiabatic reactor models are used for sensitivity analysis and ignition delay time of the chemical reaction mechanism.The results showed that the minimum burst pressure required for self-ignition increased significantly after the addition of ammonia.The maximum temperature and shock wave intensity inside the tube decreases with increasing ammonia concentration.The ignition delay time and H,HO2,and OH radicals reduce with increasing ammonia concentration.H and HO2 radicals are suggested as indicators for tracking the second and third flame branches,respectively. 展开更多
关键词 Ammonia-hydrogen energy SELF-IGNITION Shock waves Diffusion ignition Computational fluid dynamics
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Kinetics measurement of ethylene-carbonate synthesis via a fast transesterification by microreactors
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作者 Tengjie Wang Wenkai Li +2 位作者 Xuehui Ge Ting Qiu Xiaoda Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第1期243-250,共8页
High-purity ethylene carbonate(EC)is widely used as battery electrolyte,polycarbonate monomer,organic intermediate,and so on.An economical and sustainable route to synthesize high-purity ethylene carbonate(EC)via the ... High-purity ethylene carbonate(EC)is widely used as battery electrolyte,polycarbonate monomer,organic intermediate,and so on.An economical and sustainable route to synthesize high-purity ethylene carbonate(EC)via the transesterification of dimethyl carbonate(DMC)with ethylene glycol(EG)is provided in this work.However,this reaction is so fast that the reaction kinetics,which is essential for the industrial design,is hard to get by the traditional measuring method.In this work,an easy-to-assemble microreactor was used to precisely determine the reaction kinetics for the fast transesterification of DMC with EG using sodium methoxide as catalyst.The effects of flow rate,microreactor diameter,catalyst concentration,reaction temperature,and reactant molar ratio were investigated.An activity-based pseudohomogeneous kinetic model,which considered the non-ideal properties of reaction system,was established to describe the transesterification of DMC with EG.Detailed kinetics data were collected in the first 5 min.Using these data,the parameters of the kinetic model were correlated with the maximum average error of 11.19%.Using this kinetic model,the kinetic data at different catalyst concentrations and reactant molar ratios were predicted with the maximum average error of 13.68%,suggesting its satisfactory prediction performance. 展开更多
关键词 Microreactor KINETICS Ethylene carbonate synthesis TRANSESTERIFICATION Sodium methoxide
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Facile synthesis of efficient pentaethylenehexamine-phosphotungstic acid heterogeneous catalysts for oxidative desulfurization
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作者 Chongfu Wu Changsheng Chen +4 位作者 Zhaoyang Qi Jie Chen Qinglian Wang Changshen Ye Ting Qiu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第11期140-147,共8页
The ultra-deep desulfurization of oil needs to be solved urgently due to various problems,including environmental pollution and environmental protection requirements.Oxidative desulfurization(ODS)was considered to be ... The ultra-deep desulfurization of oil needs to be solved urgently due to various problems,including environmental pollution and environmental protection requirements.Oxidative desulfurization(ODS)was considered to be the most promising technology.The facile synthesis of highly efficient and stable HPW-based heterogeneous catalysts for oxidative desulfurization is still a challenging task.In this paper,pentamethylene hexamine(PEHA)and phosphotungstic acid(HPW)were combined by a simple one-step method to prepare a heterogeneous catalyst of PEHA-HPW for the production of ultra-deep desulfurization fuel oil.The composite material exhibited excellent catalytic activity and high recyclability,which could reach a 100% dibenzothiophene(DBT)removal rate in 30 min and be recycled at least 5 times.Experiments and DFT simulations were used to better examine the ODS mechanism of PEHA-HPW.It was proved that the rich amino groups on the surface of PEHA-HPW play a crucial role.This work provides a simple and feasible way for the manufacture of efficient HPW-based catalysts. 展开更多
关键词 OXIDATION CATALYST DESULFURIZATION FUEL Phosphotungstic acid AMINO
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Impacts of support properties on the vacuum residue slurry-phase hydrocracking performance of Mo catalysts
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作者 Wei-Wei Feng Ye-Gui Qian +4 位作者 Ting-Hai Wang Qing-Yan Cui Yuan-Yuan Yue Pei Yuan Xiao-Jun Bao 《Petroleum Science》 SCIE EI CAS CSCD 2023年第4期2575-2584,共10页
To deeply understand the effects of support properties on the performance of Mo-based slurry-phase hydrocracking catalysts,four Mo-based catalysts supported on amorphous silica alumina(ASA),γ-Al_(2)O_(3),ultra-stable... To deeply understand the effects of support properties on the performance of Mo-based slurry-phase hydrocracking catalysts,four Mo-based catalysts supported on amorphous silica alumina(ASA),γ-Al_(2)O_(3),ultra-stable Y(USY)zeolite and SiO_(2) were prepared by the incipient wetness impregnation method,respectively,and their catalytic performances were compared in the vacuum residue(VR)hydrocracking process.It is found that the Mo/ASA catalyst exhibits the highest VR conversion among the different catalysts,indicating that both the appropriate amount of acid sites,especially B acid sites and larger mesoporous volume of ASA can enhance the VR hydrocracking into light distillates.Furthermore,Mo catalysts supported on the different supports show quite different product distributions in VR hydrocracking.The Mo/ASA catalyst provides higher yields of naphtha and middle distillates and lower yields of gas and coke compared with other catalysts,it is attributed to the highest MoS_(2) slab dispersion,the highest sulfuration degree of Mo species,and the most Mo atoms located at the edge sites for the Mo/ASA catalyst,as observed by HRTEM and XPS analyses.These features of Mo/ASA are beneficial for the hydrogenation of intermediate products and polycyclic aromatic hydrocarbons to restrict the gas and coke formation. 展开更多
关键词 Slurry-phase hydrocracking Vacuum residue Supports Catalytic performance
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Oxygen vacancy defects engineering on Cu-doped Co_(3)O_(4) for promoting effective COS hydrolysis
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作者 Guanyu Mu Yan Zeng +5 位作者 Yong Zheng Yanning Cao Fujian Liu Shijing Liang Yingying Zhan Lilong Jiang 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第3期831-841,共11页
The activation of H_(2)O is a key step of the COS hydrolysis,which may be tuned by oxygen vacancy defects in the catalysts.Herein,we have introduced Cu into Co_(3)O_(4) to regulate the oxygen vacancy defect content of... The activation of H_(2)O is a key step of the COS hydrolysis,which may be tuned by oxygen vacancy defects in the catalysts.Herein,we have introduced Cu into Co_(3)O_(4) to regulate the oxygen vacancy defect content of the catalysts.In situ DRIFTS and XPS spectra reveal that COS and H_(2)O are adsorbed and activated by oxygen vacancy.The 10 at%Cu doped Co_(3)O_(4) sample(10Cu-Co_(3)O_(4))exhibits the optimal activity,100%of COS conversion at 70℃.The improved oxygen vacancies of CueCo_(3)O_(4) accelerate the activation of H_(2)O to form active -OH.COS binds with hydroxyl to form the intermediate HSCO^(-)_(2),and then the activated-OH on the oxygen vacancy reacts with HSCO^(-)_(2) to form HCO^(-)_(3).Meanwhile,the catalyst exhibits high catalytic stability because copper species(Cu+/Cu^(2+))redox cycle mitigate the sulfation of Co_(3)O_(4)(Co^(2+)/Co^(3+)).Our work offers a promising approach for the rational design of cobalt-related catalysts in the highly efficient hydrolysis COS process. 展开更多
关键词 Oxygen vacancy COS hydrolysis In situ spectra Cu doped Co_(3)O_(4)
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Styrene epoxidation catalyzed by polyoxometalate/quaternary ammonium phase transfer catalysts: The effect of cation size and catalyst deactivation mechanism
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作者 Qiongna Xiao Yuyan Jiang +3 位作者 Weiqiang Yuan Jingjing Chen Haohong Li Huidong Zheng 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第3期192-201,共10页
Catalytic epoxidation of alkenes is an important type of organic reaction in chemical industry,and the deep insight into catalyst deactivation will help to develop new epoxidation process.In this work,series of quater... Catalytic epoxidation of alkenes is an important type of organic reaction in chemical industry,and the deep insight into catalyst deactivation will help to develop new epoxidation process.In this work,series of quaternary ammoniums bearing different cationic sizes,i.e.MTOA+(methyltrioctylammonium,[(C_(8)H_(17))_(3)CH_(3)N]+),HTMA+(hexadecyltrimethylammonium,[(C_(16)H_(33))(CH_(3))_(3)N]+) and DMDOA+(dimethyldioctadecylammonium,[(C_(18)H_(37))_(2)(CH_(3))_(2)N]+) were incorporated with polyoxometalate (POM) anions to prepare phase transfer catalysts (PTCs),which were used in the styrene epoxidations.Among them,(MTOA)_(3)PW_(4)O_(24)exhibits the best catalytic performance judged from the highest styrene conversion rate(52%) and styrene oxide selectivity (93%),during which the styrene epoxidation conditions were optimized.Meanwhile,the deactivation mechanism of this kind of PTCs was proposed firstly,i.e.in the case of low H_(2)O_(2) content,the oxidant can only be used in the styrene epoxidation,in which the catalyst can transform into stable Keggin-type POM.But when the content of H_(2)O_(2) is higher,the excess H_(2)O_(2) can reactivate the Keggin-type POM into active (PW_(4)O_(24))_(3)-anions,which can trigger the ring-opening polymerization of styrene oxide.Consequently,the catalyst is deactivated by adhered poly(styrene oxide)irreversibly,which was determined by NMR spectra.In this situation,the active moiety{PO_(4)[WO(O_(2))_(2)]_(4)}_(3)-in phase-transfer catalytic system can break into some unidentified species with low W/P ratio with the presence of epoxides.This work will be beneficial for the design of new PTCs in alkene epoxidation in fine chemical industry. 展开更多
关键词 Phosphotungstic acid phase-transfer CATALYST Styrene epoxidation Catalyst deactivation mechanism Cation size effect
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Osteoimmunity-regulating biomaterials promote bone regeneration
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作者 Zongtai Liu Jin Zhang +1 位作者 Changfeng Fu Jianxun Ding 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2023年第1期1-3,共3页
Osteoimmunomodulation is a fascinating approach for balancing osteoimmune through regulating reciprocal interactions between bone cells and immune cells[1].Implantation of the osteoimmunity-regulating biomaterials reg... Osteoimmunomodulation is a fascinating approach for balancing osteoimmune through regulating reciprocal interactions between bone cells and immune cells[1].Implantation of the osteoimmunity-regulating biomaterials regulates osteoimmune conditions in the host dynamically,thus intensifying osseointegration under physiological microenvironments[1].This perspective presents a brief overview of osteoimmunity-regulating biomaterials for augmenting bone regeneration based on a recently published study by our research team[2]. 展开更多
关键词 IMMUNITY BIOMATERIALS BONE
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Triggering in-plane defect cluster on MoS_(2) for accelerated dinitrogen electroreduction to ammonia 被引量:3
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作者 Wanru Liao Ke Xie +5 位作者 Lijuan Liu Xiuyun Wang Yu Luo Shijing Liang Fujian Liu Lilong Jiang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第11期359-366,I0008,共9页
Electrochemical nitrogen reduction reaction (eNRR) is an alternative promising manner for sustainable N2 fixation with low-emission. The major challenge for developing an efficient electrocatalyst is the cleaving of t... Electrochemical nitrogen reduction reaction (eNRR) is an alternative promising manner for sustainable N2 fixation with low-emission. The major challenge for developing an efficient electrocatalyst is the cleaving of the stable Ntriple bondN triple bonds. Herein, we design a new MoS_(2) with in-plane defect cluster through a bottom-up approach for the first time, where the defect cluster is composed of three adjacent S vacancies. The well-defined in-plane defect clusters could contribute to the strong chemical adsorption and activation towards inert nitrogen, achieving an excellent eNRR performance with an ammonia yield rate of 43.4 ± 3 μg h^(−1) mgcat.^(−1) and a Faradaic efficiency of 16.8 ± 2% at −0.3 V (vs. RHE). The performance is much higher than that of MoS_(2) with the edge defect. Isotopic labeling confirms that N atoms of produced NH4+ originate from N2. Furthermore, the in-plane defect clusters realized the alternate hydrogenation of nitrogen in a side-on way to synthesize ammonia. This work provides a prospecting strategy for fine-tuning in-plane defects in a catalyst, and also promotes the progress of eNRR. 展开更多
关键词 In-plane defect clusters Ammonia synthesis MoS_(2) ELECTROCATALYSIS Isotopic labeling
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Stimuli-responsive emulsions:Recent advances and potential applications 被引量:2
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作者 Xue-hui Ge Liangji Mo +4 位作者 Anhe Yu Chenzi Tian Xiaoda Wang Chen Yang Ting Qiu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第1期193-209,共17页
Responsive emulsions are the emulsions that can be reversibly switched on-demand between“stable”and“unstable”by environmental stimulus or trigger,which allows a simple and effective adjustment approach to achieve ... Responsive emulsions are the emulsions that can be reversibly switched on-demand between“stable”and“unstable”by environmental stimulus or trigger,which allows a simple and effective adjustment approach to achieve emulsification and demulsification.In recent years,stimuli-responsive emulsions acting as smart soft material are received considerable attention with the advantages of simple manipulation,good reversibility,low cost,easy treatment,and little effect on the system.In this paper,the recent research progress of emulsions that can respond to external stimuli,including pH,light,magnetic field,CO_(2)/N_(2) and dual responsive are reviewed.Also,the potential applications based on responsive emulsion are discussed,such as catalytic reactions,heavy oil recovery,polymer particles synthesis and optical sensor,aiming to summarize the latest achievements and put forward the possible development trends of responsive emulsions. 展开更多
关键词 STIMULI-RESPONSIVE Emulsions Switchable surfactants INTERFACE
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Bimetallic PtSn nanoparticles confined in hierarchical ZSM-5 for propane dehydrogenation 被引量:2
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作者 Tianlei Wang Zhikang Xu +3 位作者 Yuanyuan Yue Tinghai Wang Minggui Lin Haibo Zhu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第1期384-391,共8页
A series of PtSn/hierarchical ZSM-5 catalysts were developed for propane dehydrogenation,in which the PtSn bimetallic particles are confined in the mesopores of hierarchical ZSM-5 zeolite.The synthesis of PtSn/hierarc... A series of PtSn/hierarchical ZSM-5 catalysts were developed for propane dehydrogenation,in which the PtSn bimetallic particles are confined in the mesopores of hierarchical ZSM-5 zeolite.The synthesis of PtSn/hierarchical ZSM-5 catalysts was achieved via the loading of Pt and Sn species onto the hierarchical ZSM-5 catalysts that are obtained through a desilication of conventional ZSM-5.The PtSn/hierarchical ZSM-5 catalysts were fully characterized by XRD,N_(2) adsorption,STEM,XPS,and CO-IR techniques,which reveals that highly dispersed PtSn bimetallic nanoparticles are enclosed into mesopores of hierarchical ZSM-5.The catalytic performance of PtSn/hierarchical ZSM-5 is greatly affected by the concentrations of alkali solution in the desilication process and Sn/Pt ratios in PtSn bimetallic particles.The PtSn1.00/ZSM-5(0.8)catalyst shows the highest efficiency in propane dehydrogenation,which gives an initial conversion of 46%and selectivity of 98%at 570℃.The high efficiency in these PtSn/hierarchical ZSM-5 catalysts for propane dehydrogenation is mainly ascribed to the confinement of PtSn particles in the mesopores of hierarchical ZSM-5 zeolite. 展开更多
关键词 Hierarchical ZSM-5 Propane dehydrogenation DESILICATION PtSn particles
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Redistributing Cu species in Cu-SSZ-13 zeolite as NH3-SCR catalyst via a simple ion-exchange 被引量:2
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作者 Ben Liu Nangui Lv +5 位作者 Chan Wang Hongwei Zhang Yuanyuan Yue Jingdong Xu Xiaotao Bi Xiaojun Bao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第1期329-341,共13页
The nature and distribution of Cu species in Cu-SSZ-13 play a vital role in selective catalytic reduction of NO by NH3(NH3-SCR),but existing methods for adjusting the Cu distribution are complex and difficult to contr... The nature and distribution of Cu species in Cu-SSZ-13 play a vital role in selective catalytic reduction of NO by NH3(NH3-SCR),but existing methods for adjusting the Cu distribution are complex and difficult to control.Herein,we report a simple and effective ion-exchange approach to regulate the Cu distribution in the one-pot synthesized Cu-SSZ-13 that possesses sufficient initial Cu species and thus provides a“natural environment”for adjusting Cu distribution precisely.By using this proposed strategy,a series of Cu-SSZ-13x zeolites with different Cu contents and distributions were obtained.It is shown that the dealumination of the as-synthesized Cu-SSZ-13 during the ion-exchange generates abundant vacant sites in the double six-membered-rings of the SSZ-13 zeolite for relocating Cu2+species and thus allows the redistribution of the Cu species.The catalytic results showed that the ion-exchanged Cu-SSZ-13 zeolites exhibit quite different catalytic performance in NH3-SCR reaction but superior to the parent counterpart.The structure–activity relationship analysis indicates that the redistribution of Cu species rather than other factors(e.g.,crystallinity,chemical composition,and porous structure)is responsible for the improved NH3-SCR performance and SO_(2) and H_(2)O resistance.Our work offers an effective method to precisely adjust the Cu distribution in preparing the industrial SCR catalysts. 展开更多
关键词 CATALYST ZEOLITE Cu-SSZ-13 Ion-exchange Redistribution of Cu species Selective catalytic reduction(SCR)
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Efficient homogenous catalysis of CO_(2) to generate cyclic carbonates by heterogenous and recyclable polypyrazoles 被引量:1
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作者 Zhen Lu Jie He +4 位作者 Bogeng Guo Yulai Zhao Jingyu Cai Longqiang Xiao Linxi Hou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第3期110-115,共6页
The cycloaddition between CO_(2)and epoxides to produce cyclic carbonate is an attractive and efficiency pathway for the utilization of CO_(2)as C1 source.The development of catalyst to mediate cycloaddition between C... The cycloaddition between CO_(2)and epoxides to produce cyclic carbonate is an attractive and efficiency pathway for the utilization of CO_(2)as C1 source.The development of catalyst to mediate cycloaddition between CO_(2)and epoxides at low temperature and pressure is still a challenge.Herein,a series of polypyrazoles with glass transition temperature(T_(g))in the range of 42.3-52.5℃ were synthesized and served as catalyst to mediate the cycloaddition of CO_(2)and epoxides by the assistant of tetrabutylammonium bromide.The catalytic behaviors of polypyrazole on the model cycloaddition of CO_(2)to epichlorohydrin,including the reaction parameters optimization and versatility were investigated in detail,and excellent yield(99.9%)and selectivity(99%)were obtained under the optimized reaction conditions of70℃ and 1.0 MPa for 6.0 h.Noteworthily,the polypyrazole acts as homogeneous catalyst during reaction(higher than T_(g)).And under room temperature,polypyrazoles can be easily separated and recovered,which is a promising feature of a heterogeneous catalyst.Furthermore,the reaction mechanism was proposed.The DFT calculation suggested that the formation of hydrogen bond between pyrazole and epoxide greatly reduced the energy barrier,which play an important role in promoting CO_(2)cycloaddition. 展开更多
关键词 Carbon dioxide CO_(2)conversion Cyclic carbonate Heterogeneous catalysis Polypyrazole
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Ionic liquids as entrainer in extractive distillation for effectively separating 1-propanol–water azeotropic mixture
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作者 Xinqiang You Kai Zhao +1 位作者 Ling Li Ting Qiu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第9期224-233,共10页
Economically separating 1-propanol(NPA)from water is an emergent issue for producing pharmaceutical intermediates such as n-propyl acetate,n-propylamine and so on.In this work,fourionic liquids(ILs)1-ethyl-3-methylimi... Economically separating 1-propanol(NPA)from water is an emergent issue for producing pharmaceutical intermediates such as n-propyl acetate,n-propylamine and so on.In this work,fourionic liquids(ILs)1-ethyl-3-methylimidazolium thiocyanate([EMIM][SCN]),1-butyl-3-methylimidazolium tetrafluoroborate([BMIM][BF_(4)]),1,3-dimethylimidazolium methylsulfate([MMIM][MS]),1,3-dimethylimidazolium dimethylphosphate([MMIM][DMP])were introduced as potential entrainers for separating NPA–water azeotropic mixture.The results show that[MMIM][MS]is the most suitable entrainer compared with other ILs from the analysis of vapor-liquid equilibrium and relative volatilities.The extractive distillation process with the entrainer regeneration system of flash tank and stripper was employed and optimized by the two-step optimization method.The results show that total annual cost and energy consumption per product flow rate were reduced by 39.79%and 60.47%compared with literature.In addition,the efficiency indicator of extractive section,efficiency indicator of per tray in extractive section,carbon dioxide emissions were also selected as the evaluation index for selection of operating parameters and calculated for different cases.The CO_(2)emissions of the optimal design can be reduced by 60.98%from environmental aspect. 展开更多
关键词 Ionic liquids(ILs) Extractive distillation(ED) Process optimization Energy saving Evaluation indicator Optimal design
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High-efficiency and safe synthesis of tonalid via two Friedel-Crafts reactions in continuous-flow microreactors
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作者 Yang Han Yuanyuan Liu +3 位作者 Shiwei Wang Xuehui Ge Xiaoda Wang Ting Qiu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第12期126-135,共10页
Tonalid,an important fragrance ingredient with widespread applicatio n,was synthesized via two FriedelCrafts reactions,which were catalyzed by AlCl_(3).The traditional tonalid production was conducted in batch stirrin... Tonalid,an important fragrance ingredient with widespread applicatio n,was synthesized via two FriedelCrafts reactions,which were catalyzed by AlCl_(3).The traditional tonalid production was conducted in batch stirring tank reactors,suffering from low production capacity and the safety hazard of temperature runaway.To solve these problems,the continuous-flow technologies were developed for the highefficiency and intrinsically safe synthesis of tonalid in microreactors.Catalyst AlCl_(3)was neatly homogenized in proper solvents by forming complex with reactant,which was a necessary step for the continuous synthesis in microreactors.Several reaction conditions,including reactant molar ratio,catalyst concentration,temperature,and microchannel hydrodynamic diameter,were investigated for the two Friedel-Crafts reactions in micro reactors.At optimized conditions,the yields of the two Friedel-Crafts reactions were 44.15%and 97.55%,respectively.In comparison with the batch reactors,the reaction times of these two reactions could both be reduced by nearly two thirds in microreactors at the similar yield. 展开更多
关键词 MICROREACTOR Continuous synthesis Process intensification Tonalid Friedel-Crafts reaction
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Efficient and reversible separation of NH_(3) by deep eutectic solvents with multiple active sites and low viscosities
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作者 Jiayin Zhang Lu Zheng +4 位作者 Siqi Fang Hongwei Zhang Zhenping Cai Kuan Huang Lilong Jiang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS 2024年第3期97-105,共9页
The efficient separation and collection of ammonia(NH_(3))during NH_(3) synthesis process is essential to improve the economic efficiency and protect the environment.In this work,ethanolammonium hydrochloride(EtOHACl)... The efficient separation and collection of ammonia(NH_(3))during NH_(3) synthesis process is essential to improve the economic efficiency and protect the environment.In this work,ethanolammonium hydrochloride(EtOHACl)and phenol(PhOH)were used to prepare a novel class of deep eutectic solvents(DESs)with multiple active sites and low viscosities.The NH_(3) separation performance of EtOHAClþPhOH DESs was analyzed completely.It is figured out that the NH_(3) absorption rates in EtOHAClþPhOH DESs are very fast.The NH_(3) absorption capacities are very high and reach up to 5.52 and 10.74 mol·kg1 at 11.2 and 100.4 kPa under 298.2 K,respectively.In addition,the EtOHAClþPhOH DESs present highly selective absorption of NH_(3) over N_(2) and H_(2) and good regenerative properties after seven cycles of absorption/desorption.The intrinsic separation mechanism of NH_(3) by EtOHAClþPhOH DESs was further revealed by spectroscopic analysis and quantum chemistry calculations. 展开更多
关键词 Separation Absorption Ionic liquid Deep eutectic solvent Multiple active site Low viscosity
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锌离子传导聚合物缓冲层:抑制锌离子水电池锌负极寄生反应
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作者 陈丹灵 王辉波 +7 位作者 任丽 朱梦宇 白正帅 李春新 施灿盛 王汇才 汤育欣 张焱焱 《Science China Materials》 SCIE EI CAS CSCD 2023年第12期4605-4614,共10页
由于锌金属在电解液中热力学不稳定而自发地发生寄生反应(析氢、枝晶生长等),水系锌离子电池的商业化应用受到了阻碍.因此,我们构建了一种高粘附性的锌离子传导聚合物聚乙烯醇缩甲醛(PVF)缓冲层,来抑制这些寄生反应的发生,从而提高锌沉... 由于锌金属在电解液中热力学不稳定而自发地发生寄生反应(析氢、枝晶生长等),水系锌离子电池的商业化应用受到了阻碍.因此,我们构建了一种高粘附性的锌离子传导聚合物聚乙烯醇缩甲醛(PVF)缓冲层,来抑制这些寄生反应的发生,从而提高锌沉积的可逆性.这种致密的人工缓冲层不仅能有效隔绝电解质与锌负极之间的直接接触,还能适应锌沉积/剥离过程中的体积膨胀,并引导锌成核过程.具体来说,PVF层可提高成核过电位,并促进Zn2+的三维扩散过程,使PVF层下的Zn2+沉积通量均匀化.我们设计的PVF@Zn具有高循环稳定性和不易生成枝晶的特点,基于该电极的对称电池的长循环寿命超过5200 h,比Zn负极电池提高了近35倍,甚至可以在40.0 mA cm^(−2)的超高电流密度下稳定运行.此外,PVF@Zn||NVO全电池在1.0 A g^(−1)的条件下进行2400个循环后,仍能保持172.4 mA h g^(−1)的比容量.这种通过消除自发寄生反应并调节锌均匀沉积及成核的策略,为设计实用化高性能锌负极提供了重要借鉴. 展开更多
关键词 buffer polymer layer polyvinyl formal spontaneous parasitic reactions Zn dendrite hydrogen evolution nucleation overpotential
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Rational designed ZIF-8@PDA@PDMS composite sponge for efficient and sustainable particulate matter filtering under harsh environment
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作者 Yukui Gou Yuanye Hao +2 位作者 Weilong Cai Jianying Huang Yuekun Lai 《Particuology》 SCIE EI CAS CSCD 2023年第5期141-150,共10页
Particulate matter(PM)is a significant danger to both environment and human health.Despite the development of a series of air filters,they do not work well in harsh environment such as high tem-perature,high humidity ... Particulate matter(PM)is a significant danger to both environment and human health.Despite the development of a series of air filters,they do not work well in harsh environment such as high tem-perature,high humidity or long-time filtration.To make a three-dimensional(3D)particle capture de-vice,a sacrificial template approach was used to manufacture polydimethylsiloxane(PDMS)sponge,and then zeolite imidazole framework-8(ZIF-8)was grown in situ on the 3D network of PDMS sponge.The removal efficiency of PM_(2.5)or PM10 is greater than 99.8%because of the high specific surface area and porous network structure of PDMS sponge,as well as the large number of metal sites of ZIF-8.In addition,the sponge filter has long-term filtration stability and still achieves excellent performance after 65 h of filtration.The composite sponge can adapt to harsh environments such as high temperature(250℃)and high humidity(90%RH).Composite sponge filter has a regular shape,and it may be customized to any shape as required.This study provides a new idea for designing 3D high-efficiency air filters that can adapt to harsh environments. 展开更多
关键词 PDMS sponge ZIF-8 Particle capture High temperature Stability
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