Unveiling the tailorable electrochemical properties of zeolitic imidazolate framework-derived Ni-doped LiCoO_(2) for lithium-ion batteries in half/full cells

As a prevailing cathode material of lithium-ion batteries(LIBs),LiCoO_(2)(LCO)still encounters the tricky problems of structural collapse,whose morphological engineering and cation doping are crucial for surmounting the mechanical strains and alleviating phase degradation upon cycling.Hereinafter,we propose a strategy using a zeolitic imidazolate framework(ZIF)as the self-sacrificing template to directionally prepare a series of LiNi_(0.1)Co_(0.9)O_(2)(LNCO)with tailorable electrochemical properties.The rational selection of sintering temperature imparts the superiority of the resultant products in lithium storage,during which the sample prepared at 700℃(LNCO-700)outperforms its counterparts in cyclability(156.8 mA h g^(-1)at 1 C for 200 cycles in half cells,1 C=275 mA g^(-1))and rate capability due to the expedited ion/electron transport and the strengthen mechanical robustness.The feasibility of proper Ni doping is also divulged by half/full cell tests and theoretical study,during which LNCO-700(167 mA h g^(-1)at 1 C for 100 cycles in full cells)surpasses LCO-700 in battery performance due to the mitigated phase deterioration,stabilized layered structu re,ameliorated electro nic co nductivity,a nd exalted lithium sto rage activity.This work systematically unveils tailorable electrochemical behaviors of LNCO to better direct their practical application.

Stellerite-seeded facile synthesis of zeolite X with excellent aqueous Cd^(2+)and Ni^(2+)adsorption performance

Zeolite X was synthesized by a two-step hydrothermal method using natural stellerite zeolite as the silicon seed,and its adsorption performance for Cd^(2+)and Ni^(2+)ions was experimentally and comprehensively investigated.The effects of p H,zeolite X dosage,contact time,and temperature on adsorption performance for Cd^(2+)and Ni^(2+)ions over were studied.The adsorption process was endothermic and spontaneous,and followed the pseudo-second-order kinetic and the Langmuir isotherm models.The maximum adsorption capacitiesfor Cd^(2+)and Ni^(2+)ions at 298 K were 173.553 and 75.897 mg.g-1,respectively.Ion exchange and precipitation were the principal mechanisms for the removal of Cd^(2+)ions from aqueous solutions by zeolite X,followed by electrostatic adsorption.Ion exchange was the principal mechanisms for the removal of Ni^(2+)ions from aqueous solutions by zeolite X,followed by electrostatic adsorption and precipitation.The zeolite X converted from stellerite zeolite has a low n(Si/Al),abundant hydroxyl groups,and high crystallinity and purity,imparting a good adsorption performance for Cd^(2+)and Ni^(2+)ions.This study suggests that zeolite X converted from stellerite zeolite could be a useful environmentally-friendly and effective tool for the removal of Cd^(2+)and Ni^(2+)ions from aqueous solutions.

Fabrication of lithium silicates from zeolite for CO2 capture at high temperatures

Li4Si O4 has been regarded as one of the most promising high-temperature CO2 sorbents.However,for practical applications,its CO2sorption kinetics,cycling stability and sorption properties at lower temperatures or lower CO2 concentrations have to be improved.In this contribution,four Li4Si O4 sorbents were synthesized from zeolite precursors MCM-41,MCM-48,TS-1,and ZSM-5.The CO2 uptake,cycling stability and the optimal CO2 sorption conditions were investigated.Among the samples,MCM-41-Li4Si O4 showed the best cycling stability at 650°C,with a stable reversible CO2 uptake of 29.1 wt%under 100 vol%CO2 during 20 cycles.But its sorption kinetics and CO2 uptakes at lower temperatures and lower CO2 concentrations need to be improved.We then demonstrated that the sorption kinetics can be improved by modifying the MCM-41 precursor with metals such as Al,Ti,Ca,and Na.The Na-MCM-41-Li4Si O4 sample exhibited the highest sorption rate,and reached the equilibrium sorption capacity close to the theoretical value of 36.7 wt%within 20 min.In addition,we proved that coating the MCM-41-Li4Si O4with Na2CO3and K2CO3can significantly increase the CO2uptakes at lower temperatures(e.g.550℃)and lower CO2concentrations(10–20 vol%).At 550℃ and under 20 vol%CO2,15 wt%K2CO3-MCM-41-Li4Si O4 and 10 wt%Na2CO3-MCM-41-Li4Si O4 sorbents resulted in a CO2 uptake of 32.2 wt%and 34.7 wt%,respectively,which are much higher than that of MCM-41-Li4Si O4(11.8 wt%).These two sorbents also showed good cycling stability.The promoiting mechasnim by alkali carbonate coating was discussed by a doubleshell model.

Amine-immobilized HY zeolite for CO_(2) capture from hot flue gas

Solid amine-based adsorbents were widely studied as an alternative to liquid amine for post-combustion CO_(2)capture(PCC).However,most of the amine adsorbents suffer from low thermal stability and poor cyclic regenerability at the temperature of hot flue gases.Here we present an amine loaded proton type Y zeolite(HY)where the amines namely monoethanolamine(MEA)and ethylenediamine(ED)are chemical immobilized via ionic bond to the zeolite framework to overcome the amine degradation problem.The MEA and ED of 5%,10%and 20%(mass)concentration-immobilized zeolites were characterized by X-ray diffraction,Fourier-transform infrared spectroscopy,and N_(2)-196℃ adsorption to confirm the structure integrity,amine functionalization,and surface area,respectively.The determination of the amine loading was given by C,H,N elemental analysis showing that ED has successfully grafted almost twice as many amino groups as MEA within the same solvent concentration.CO_(2)adsorption capacity and thermal stability of these samples were measured using thermogravimetric analyser.The adsorption performance was tested at the adsorption temperature of 30,60 and 90℃,respectively using pure CO_(2)while the desorption was carried out with pure N_(2)purge at the same temperature and then followed by elevated temperature at 150℃.It was found that all the amine@HY have a substantial high selectivity of CO_(2)over N_(2).The sample 20%ED@HY has the highest CO_(2)adsorption capacity of1.76 mmol·g^(-1)at 90℃ higher than the capacity on parent Na Y zeolite(1.45 mmol·g^(-1)only).The amine@HY samples presented superior performance in cyclic thermal stability in the condition of the adsorption temperature of 90℃ and the desorption temperature of 150℃.These findings will foster the design of better adsorbents for CO_(2)capture from flue gas in post-combustion power plants.

Preparation of Calcium Cross-linked Nano-Fe3O4 Modified Zeolite Microspheres for Cu^2+ Adsorption from Wastewater

Artificial zeolite was modified by nano-Fe3O4 for development of functional adsorbents.Subsequently,adsorbents such as calcium cross-linked nano-Fe3O4 microspheres (Ca-MS),calcium cross-linked nano-Fe3O4 modified zeolite microspheres (Ca-MZS) and iron cross-linked nano-Fe3O4 modified zeolite microspheres (Fe-MZS) were prepared and compared for their adsorption performance.The effects of adsorbent dosage,solution pH,initial concentration and ion content on the removal of Cu^2+ from wastewater are investigated,and the adsorption kinetics and isotherms for the adsorbent materials were analyzed.The experimental results indicate that for the initial concentration of Cu^2+ of 30 mg/L,the adsorption is noted to be most stable.The optimal initial pH for adsorbing Cu^2+ is observed to be 5.5.At an optimal dosage of Ca-MZS of 900 mg/L,the adsorption capacity is measured to be 28.25 mg/g,along with the removal rate of 72.49%.The addition of Na+ and K+ affects the adsorption of Cu^2+.For the Na^+ and K^+ concentration of 0.2 mmol/L,the Cu^2+ removal rate by Ca-MZS drops to 11.94% and 22.12%,respectively.As compared with the adsorbents such as Natural Zeolite (NZ),Ca-MS and Fe-MZS,Ca-MZS demonstrates the best removal effect in solution,where the removal rate reaches 84.27%,with the maximum adsorption capacity of 28.09 mg/g.The Cu^2+ adsorption kinetics of Ca-MZS is observed to follow the Elovich kinetic model,with the adsorption isotherm data fitting the Freundlich isotherm model by using the non-linear method.

CoFe_(2)O_(4)@Zeolite催化剂活化过一硫酸盐对甲基橙的强化降解:性能与机理

采用共沉淀水热法制备了CoFe_(2)O_(4)@Zeolite(CFZ),并将其用于活化过一硫酸盐(PMS)降解合成染料。综合表征表明,组成多孔壳层的CoFe_(2)O_(4)纳米颗粒均匀地覆盖在Na-A沸石上。CFZ的比表面积为107.06 m^(2)/g,是原始沸石比表面积的3倍。CFZ的饱和磁化强度为29.0 A·m^(2)·kg^(–1),可以进行有效磁分离。催化降解实验表明,CFZ/PMS体系对甲基橙(MO)的去除率远远高于单独使用CFZ或PMS。在最佳条件([MO]=50 mg/L、[PMS]=1.0 mmol/L、0.2 g/L CFZ、pH 8和T=25℃)下,MO去除率可达到97.1%。实验研究了pH、PMS用量、CFZ用量、MO浓度以及共存阴离子等因素对CFZ催化性能的影响。活性氧粒子淬灭实验表明,1O2和O_(2)^(•–)在降解过程中起主导作用。CFZ具有良好的回收性能,5次循环后MO去除效率仅下降2.4%。本文还详细讨论了CFZ/PMS体系的催化降解机理。

Boosting Zn||I_(2) Battery’s Performance by Coating a Zeolite‑Based Cation‑Exchange Protecting Layer

The intrinsically safe Zn||I_(2) battery,one of the leading candidates aiming to replace traditional Pb-acid batteries,is still seriously suffering from short shelf and cycling lifespan,due to the uncontrolled I_(3)^(−)-shuttling and dynamic parasitic reactions on Zn anodes.Considering the fact that almost all these detrimental processes terminate on the surfaces of Zn anodes,modifying Zn anodes’surface with protecting layers should be one of the most straightforward and thorough approaches to restrain these processes.Herein,a facile zeolite-based cation-exchange protecting layer is designed to comprehensively suppress the unfavored parasitic reactions on the Zn anodes.The negatively-charged cavities in the zeolite lattice provide highly accessible migration channels for Zn^(2+),while blocking anions and electrolyte from passing through.This low-cost cation-exchange protecting layer can simultaneously suppress self-discharge,anode corrosion/passivation,and Zn dendrite growth,awarding the Zn||I_(2) batteries with ultra-long cycle life(91.92%capacity retention after 5600 cycles at 2 A g^(−1)),high coulombic efficiencies(99.76%in average)and large capacity(203–196 mAh g^(−1) at 0.2 A g^(−1)).This work provides a highly affordable approach for the construction of high-performance Zn-I_(2) aqueous batteries.

Preparation and characterization of Ag^+ ion-exchanged zeolite-Matrimid~5218 mixed matrix membrane for CO_2/CH_4 separation

In this work, the zeolite-Y was ion-exchanged by introducing silver cations into the framework of microsized nano-porous sodium zeolite-Y using a liquid-phase ion exchanged method. The Ag+ion-exchanged zeolite, was then embedded into the Matrimid5218 matrix to form novel mixed matrix membranes(MMMs). The particles and MMMs were characterized by ultraviolet-visible diffuse reflectance spectroscopy(UV–vis DRS), N2adsorption–desorption isotherm, X-ray diffraction(XRD), Fourier transform infrared(FTIR) and scanning electron microscopy(SEM). Furthermore, the effects of filler content(0–20wt%) on pure and mixed gas experiments, feed pressure(2–20 bar) and operating temperature(35–75 oC)on CO2/CH4transport properties of Matrimid/Ag Y MMMs were considered. Characterization results confirmed an appropriate ion-exchange treatment of the zeolites. The SEM results confirmed the superior interfacial adhesion between polymer and zeolites, particularly in the case of Matrimid/Ag Y membranes.This is due to the proper silverous zeolite/Matrimid functional groups’ interactions. The gas permeation results showed that the CO2permeability increased about 123%, from 8.34 Barrer for pure Matrimid to18.62 Barrer for Matrimid/Ag Y(15 wt%). The CO2/CH4selectivity was improved about 66%, from 36.3 for Matrimid to 60.1 for Matrimid/Ag Y(15 wt%). The privileged gas separation performance of Matrimid/Ag Y(15 wt%) was the result of a combined effect of facilitated transport mechanism of Ag+ions as well as the intrinsic surface diffusion mechanism of Y-type zeolite. In order to survey the possibility of using the developed MMMs in industry, the CO2-induced plasticization effect and mixed gas experiment were accomplished. It was deduced that the fabricated MMMs could maintain the superior performance in actual operating conditions.

Improved Stability and Shape Selectivity of 2,6-Dimethylnaphthalene by Methylation of Naphthalene with Methanol on Modified Zeolites

2,6-Dimethylnaphthalene (2,6-DMN) is a key intermediate for polyethylene naphthalate synthesis. The selective synthesis of 2,6-DMN from naphthalene and methanol was carried out over different zeolites (HZSM-5, Hβ, HUSY and SAPO-11) modified by 0.1wt% PdO under atmospheric pressure. Among the adopted zeolites, SAPO-11 exhibits exceptional shape-selectivity and stability to synthesize 2,6-dimethylnaphthalene from methylation of naphthalene, due to the special pore structure of SAPO-11 which inosculated better with 2,6-dimethylnaphthalene than with 2,7-dimethylnaphthalene.

Structural Changes of Y Zeolites with Different Initial SiO_2/Al_2O_3 Ratios during Hydrothermal Treatment

The effects of the initial framework SiO2/Al2O3 ratio and temperature on the structural changes of NaY zeolites during hydrothermal treatments are studied. Two samples with different framework SiO2/Al2O3 ratios are subjected to hydrothermal treatment at four different temperatures. For zeolite with a lower initial SiO2/Al2O3 ratio of 4.2, mesopores are easily formed because more framework aluminum is detached. Moreover, two kinds of mesopores are produced at a higher temperature due to the interconnection of vacancies and smaller mesopores. For zeolite with a higher initial SiO2/Al2O3 ratio of 6.0, there are less mesopores formed as compared with the lower initial SiO2/Al2O3 ratio sample, but there are some macropores formed. This may be attributed to the isolation of vacancies and the different distributions of aluminum in the crystal lattice of the zeolite. The experiment data show that NaY with the SiO2/Al2O3 ratio of 6.0 retains a high relative crystallinity during the hydrothermal treatment. This proves that a high framework SiO2/Al2O3 ratio benefits the stability of zeolite.

Synthesis of ITQ-2 Zeolites and Catalytic Performance in n-Dodecane Cracking

ITQ-2 zeolites were prepared by sequential alkali-swelling and ultrasonic-delamination of precursor MCM-22 and characterized by X-ray powder diffraction, scanning electron microscopy, nitrogen adsorption-desorption, ammonia temperature-programmed desorption and in-situ Fourier-transform infrared spectroscopy. The delamination induced a change in the morphology of ITQ-2 zeolites from aggregated thin platelets to scattered platelets, together with a significant increase in external specific surface area, which reached a plateau at the ultrasonic treatment time of 3 h. The catalytic cracking of n-dodecane over ITQ-2 zeolites was evaluated with ITQ-2 coated on the inside wall of a tubular reactor at 550 ℃ and 4 MPa. The sample obtained by ultrasonic treatment of 3 h （ITQ-2-3） gave the highest initial conversion of n-dodecane, whereas those of 5 h and I h gave the conversion even lower than MCM-22, which was in agreement with the trend of the ratio of strong Lewis acid to the total acid amount. Although the amount of cokes deposited on ITQ-2-3 was larger than that on MCM-22, the former deactivated slowly, suggesting that a large external specific surface area benefits the stability of zeolite coatings,

Photocatalytic Activity of TiO_2 Coating on Natural Feather Zeolite in Degradation of Orthomonochlorphenol

Ti02 coatings on natural feather zeolite are respectively prepared by a collosol （Sol-gel） method and two powder coating methods with deionizod water or dehydrated ethanol as a dispersant. During degradation of orthomono- chlorphenol solutions by ultraviolet, the strong adsorption capability of the zeolite results in increased concentration of substrate on its surface. The Ti（h film coated on feather zeolite further enhances the photocatalytic activity. The TiO~ film on the zeolite prepared by the Sol-gel method is found more effective as a catalyst than that by two powder coating methods.

Study of the Temperature-Programmed Desorption of Carbon Dioxide (CO2) on Zeolites X Modified with Bivalent Cations

Study of physisorbed and chemisorbed carbon dioxide (CO2) species was carried out on the NaX zeolite modified by cationic exchanges with bivalent cations (Ca2+ and Ba2+) by temperature-programmed desorption of CO2 (CO2-TPD). Others results were obtained by infrared to complete the study. The results of this research showed, in the physisorption region (213 - 473 K), that the cationic exchanges on NaX zeolite with bivalent cations increase slightly the interactions of CO2 molecule with adsorbents and/or cationic site. Indeed, the desorption energies of physisorbed CO2 obtained on the reference zeolite NaX (13.5 kJ·mol-1) are lower than that of exchanged zeolites E-CaX and E-BaX (15.77 and 15.17 kJ·mol-1 respectively). In the chemisorbed CO2 region (573 - 873 K), the desorption energies related to desorbed species (bidentate carbonates: CO32-) on the exchanged zeolites E-CaX and E-BaX are about 81 kJ·mol-1, higher than the desorbed species (bicarbonates: HCO32-) on the reference R-NaX (62 kJ·mol-1). In addition, the exchanged E-BaX zeolite develops the secondary adsorption sites corresponding to bicarbonates species with desorption energies of 35 kJ·mol-1 lower to desorption energies of bicarbonates noted on the reference zeolite NaX.

Preparation and characterization of A-type zeolite/SiO_2 molecular sieving membranes

To deal with the brittleness and crystal grain interfacial defects of zeolite membranes, and to confine the pore size distribution of inorganic membranes in a limited range, a process method for composite membranes of A-type zeolite/SiO 2 was discribed. A silica sol was mixed with nanocrystals of zeolite 4A in a suitable proportion, then the supported membranes was prepared by dip-coating method. The composite membranes prepared in first step was treated hydrothermally again, so nanocrystal zeolite 4A formed and located in the mesopores of the membranes, and the microstructure and pore size distribution of the membrane were modified greatly. The thermal stability, mineral phase, microstructure, and pore size distribution were examined via DTA-TG, X-ray diffractometer, scanning electron microscope (SEM), and BET equipment. The structure of the composite membranes remains high stability below 800 ℃. Its average pore size in a very limited range is smaller than that in the untreated membranes in hydrothermal condition, and the peak bands of the membrane pores are 4×10 -10 m, 1.8×10 -9 m, respectively.

类沸石型咪唑酯骨架材料制备及其CO_(2)吸附性能

由有机配体和金属离子链接的类沸石型咪唑酯骨架(ZIFs)是金属有机框架材料中独特的一个子类,其孔结构可控,且气体储存性能优异。本研究采用溶剂热法制备了ZIF-8、ZIF-9、ZIF-68三种ZIFs材料,并对其进行X射线衍射、N_(2)吸附脱附、热重、红外等测试表征。X射线衍射分析结果显示三种ZIFs材料的衍射峰与其标准卡一致,表明材料的成功制备。N_(2)吸附脱附测试结果表明ZIF-8的比表面积和孔体积最大,分别高达2 284.83 m^(2)/g和3.13 cm^(3)/g;ZIF-8、ZIF-9和ZIF-68最可几孔径分别约为1.00、6.44和0.6 nm。热重测试结果表明,ZIF-8的热稳定性最好。ZIFs材料的CO_(2)吸附性能研究结果表明ZIF-68吸附性能最高,273 K/1 bar及298 K/1 bar条件下,可达74.37和42.62 cc/g,这可能是因为ZIF-68晶体中约0.6 nm孔径更易于CO_(2)气体吸附。研究结果表明,0.6 nm孔径尺寸较易于吸附CO_(2)温室气体,且ZIFs材料是一种较理想的CO_(2)吸附材料。

ZIF-8改性自具微孔聚合物膜的制备及其对CO_(2)的分离性能

为了提高自具微孔聚合物(PIMs)膜对CO_(2)的分离效果,对PIM-1膜进行功能化改性。首先,将PIM-1膜通过水解、置换等作用引入Zn2+离子,再将改性后的PIM-1膜浸泡在2-甲基咪唑的甲醇溶液中,于室温下在膜表面生长类沸石咪唑酯框架-8(ZIF-8)选择层,经过硅橡胶填补后得到无缺陷ZIF-8改性PIM-1膜(pZIF-8@PIM-1),并对其性能和结构进行测试和表征。结果表明:在离子改性后的PIM-1膜表面成功生长了厚度约0.8μm的ZIF-8选择层,晶体尺寸大小均匀,粒径直径在200 nm左右;与PIM-1纯膜相比,由于多价金属离子交联及ZIF-8选择层的存在,pZIF-8@PIM-1的CO_(2)扩散系数明显下降,CO_(2)/N_(2)扩散选择性有所上升,由0.89提升到1.01;ZIF-8中含氮有机杂环与CO_(2)之间的Lewis酸碱作用及2-甲基咪唑环上静电势对CO_(2)的亲和作用,使得pZIF-8@PIM-1的CO_(2)溶解度系数上升,且CO_(2)/N_(2)溶解选择性也得到提升,由18.56提升到20.31;改性后的PIM-1膜CO_(2)/N_(2)扩散选择性及CO_(2)/N_(2)溶解度选择性的双重提升共同促进了CO_(2)/N_(2)分离系数的提升,由原膜的16.57增加到20.43,具有良好的CO_(2)分离性能。

Modifying NaY Zeolite with Metal Oxide by Microwave Irradiation:Influence on the Adsorption and Decomposition of N-nitrosamines

Coating MgO.br ZrO2 on zeolite NaY accelerated decomposition of N-nitrosodimethylamine and N-nitrosopyrrolidine, resulting from variation of the surface state such as generation of basic sites.

ADSORPTION EQUILIBRIUM OF ETHYLENE-CARBON DIOXIDE MIXTURE ON ZEOLITE ZSM5 AND ITS CORRELATION

Binary gas mixture adsorption equilibrium data for the ethylene-carbon dioxide system were obtained for cation exchanged forms of ZSM5 (Li^+, Na^+, K^+, Rb^+, Mg^(+2), Ca^(+2), Sr^(+2), and Ba^(+2)) for the gas phase CO_2 mole fracion of 0.766 at 308K and 101. 3kPa. The experimental adsorption phase diagrams were obtained for CO_2-C_2H_4 on NaZSM5 and MgZSM5. Single component adsorption isotherms for CO_2 and C_2H_4 were also obtained for these two zeolites. The single component data were used to obtain parameters derived in the vacancy solution model (VSM) and the statistical thermodynamic model(STM). These parameters were, in turn, used to predict binary mixture isotherms for these two zeolites. The agreement between experimental data and predicted value is generally good.

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

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

Cascade adsorptive separation of light hydrocarbons by commercial zeolites

Adsorptive separation of light hydrocarbons by porous solids provides an energy-efficient alternative to state-of-the-art cryogenic distillation.However,an optimal balance between the cost,performance and stability of the sorbent material is yet to be achieved for industrial applications.Here,we report the efficient separation of C2 and C3 hydrocarbons by a faujasite zeolite(Na-X,Si/Al=1.23).A tandem configuration of two fixed-beds packed with Na-X affords complete dynamic separation of the ternary mixture of C_(2)H_(2)/C_(2)H_(4)/C_(2)H_(6)(1/49.5/49.5;v/v/v)under ambient conditions.Pressure-swing desorption on the latter fixed-bed gives ethylene(>99.50%,1.80 mmol g^(-1))and ethane(>99.99%,1.41 mmol g^(-1)).In situ synchrotron X-ray powder diffraction revealed the binding sites for C_(2)H_(2)and C_(2)H_(4)in Na-X.This study highlights the potential application of commercial zeolites for challenging industrial separations.