Zeolite 4A Research Articles

Economically Scalable Cu-based MOFs: Vital Role of Structural Integrity towards Selectivity on Azeotropic Ethanol Dehydration.

A facile, green, and economical method for the scalable synthesis of hydrophilic copper-triazole metal-organic frameworks (Cu-trz) is demonstrated. Numerous open metal sites within the highly crystalline porous structure of Cu-trz are generated through mild thermal activation, enabling its application in liquid-phase ethanol dehydration under ambient conditions. The frameworks with distinct crystallinity and particle sizes were achieved by modifying the synthesis process. The high crystallinity of the framework plays an exclusive role in enhancing water adsorption capacity. With selective water adsorption comparable to commercial zeolite 3A, Cu-trz MOF emerges as a promising candidate for cost-effective water-ethanol separation.

Molecular Simulation of Adsorption of CO2 from a Combustion Exhaust Mixture of Zeolites with Different Topological Structures

In this work, a molecular simulation method was used to study the adsorption of seven combustion products (CO2, H2O, SO2, N2, O2, NO and NO2) on three zeolites with different topological structures (4A, MIF and MOR). Adsorption isotherms of pure components and mixtures at a wide range of temperatures (253–333 K) were calculated using the Monte Carlo method, obtaining equilibrium parameters including the adsorption capacity, adsorption heat and energy distribution. The calculation results indicated that 4A zeolite with more micropores has a stronger adsorption performance for CO2. The presence of water significantly reduced the CO2 capture efficiency of the three zeolites, and the CO2 adsorption amount decreased by more than 80%. Adsorption kinetics was studied using the molecular dynamic (MD) method, MFI and MOR, with channel-type pore structures exhibiting stronger gas diffusion performance, though their separation efficiency was not high. A 4A zeolite has the potential for kinetic separation of CO2.

Exploring Zeolite Potential for Hydrofluorocarbon Capture and Recycling: Insights from Molecular Simulations

The need for efficient separation of hydrofluorocarbons for recycling and environmental protection is critical due to their substantial impact on global warming. However, conventional methods such as cryogenic distillation face significant limitations due to the azeotropic behavior of many of these hydrofluorocarbons. This study evaluates the adsorption behavior of various hydrofluorocarbons in zeolite structures, specifically Linde Type A (3A, 4A, and 5A) and Faujasite Type X (13X), using molecular dynamics and grand canonical Monte Carlo simulations. The simulations were validated against experimental data, confirming the reliability of the computational models. Adsorption isotherms were fitted using the Langmuir-Freundlich model to describe the adsorption behavior across different pressures. Focusing on fluoromethane derivatives, the study highlighted key interactions and adsorption capacities in various zeolites. The isotherms of various hydrofluorocarbons in zeolite 13X were explored, revealing differential adsorption based on molecular structure. The potential for using zeolite 13X and 5A to separate refrigerant mixtures was also studied, showing distinct selectivity patterns. Additionally, the temperature dependence of adsorption isotherms and isosteric heat was studied to gain insights into the thermodynamics of the adsorption processes. Key results indicate that zeolite 13X demonstrates strong cation-fluorine interactions, particularly effective for the adsorption of large hydrofluorocarbon molecules, which preferentially occupy 12-membered ring windows. In contrast, zeolite 5A exhibited predominant hydrogen bonding interactions at low pressures, with hydrofluorocarbon molecules occupying the smaller 8-membered ring windows. These findings underscore the selective adsorption capabilities of these zeolites, highlighting their potential application in hydrofluorocarbon separation and recycling processes.

Effect of zeolite type in sorption-enhanced CO2 hydrogenation to methanol

The use of solid adsorbents for in-situ water removal can overcome thermodynamic constraints that limit CO2-derived methanol production to low levels. In this work, the water and methanol adsorption/desorption capacity and kinetics of four different zeolites (LTA-3A, LTA-4A, LTA-5A and FAU-13X) are investigated in a thermogravimetric setup equipped with a mass spectrometer. When water is replaced with methanol, the sorption kinetics are faster, the capacity is larger and the differences between the sorbents are more prominent. Co-adsorption is also evidenced on all zeolites. Use of the sorbents as admixtures with a commercial CuO/ZnO/Al2O3 catalyst in sorption-enhanced CO2 hydrogenation experiments at 250 °C and 70 bar increases CO2 conversion by 48–56 % and CH3OH yield by 63–70 %. Zeolites 4A and 13X demonstrate the highest performance improvement and 3A the lowest, while zeolite 5A leads to significant enhancement in methanol selectivity in agreement with the adsorption studies. Preferential methanol enhancement occurs due to the simultaneous sorption of methanol along with water. The stability, evaluated over consecutive cycles at the employed reaction-regeneration conditions, showcases zeolite 4A as the most stable adsorbent and zeolite 13X the least, in line with N2 adsorption/desorption and XRD observations.

The Effect of Synthetic Zeolite on the Curing Process and the Properties of the Natural Rubber-Based Composites.

Zeolites, known for their unique structural and catalytic properties, are added to the natural rubber matrix to investigate their influence on the vulcanization process and the resultant properties of composites. The natural rubber-based composites were masticated with 4A synthetic zeolite (0, 5, 10, 15, 20, and 30 phr). The curing of the rubber compounds was monitored on a moving die rheometer at 150 °C. The isothermal DSC method was also used to study the curing process at 150 °C, 160 °C, and 170 °C. Based on the obtained results, it is assumed that there is an interaction between the components of the curing system and the surface of the zeolite particle, and that is why the vulcanization reaction starts earlier with an increase in zeolite in the rubber mixture. This underscores the significant role of zeolite in accelerating the curing reaction of natural rubber-based compounds. The composites were vulcanized in a press at 150 °C for 15 min. The chemical structure was analyzed using FTIR, and the sample morphology was examined using SEM. The degree of swelling in toluene and distilled water was determined. The tensile strength values, modulus of elasticity at 100% and 300% elongation, and elongation at break were measured using a universal testing machine. Hardness was assessed according to the Shore A scale. With a small addition of zeolite (up to 10 phr), there is no significant change in the tensile strength values. However, adding a considerable amount of zeolite to a natural rubber matrix results in a deterioration of the tested mechanical properties. It can be assumed that with large proportions of zeolite 4A MS in the composites, the mechanical properties deteriorated due to increased porosity. The amount of added zeolite affects the initial stages of thermal decomposition of the examined samples and the rest after the analysis at a temperature of 500 °C.

Rice husk ash based complex sodium di silicate – An alternative detergent builder for sodium tripolyphosphate and Zeolite 4A

Detergent builder is an essential part of any detergent powder, as it softens the hard water which hinders the cleaning action of surfactants. Nowadays, sodium tripolyphosphate and Zeolite 4A are used as detergent builders extensively in detergent formulation. Though STPP has higher capacities to remove hardness from the water but has a detrimental impact on the environment like eutrophication and hence it has been banned for detergent application in various countries. Zeolite 4A is currently leading the detergent industry with moderate hardness removal, but it has certain disadvantages like high pH, insolubility, high solid residue in the wash water and needs additives for its activation in the detergent formulation. In this research paper, the better alternative detergent builder known as Complex sodium dislicate (CSDS) is produced using rice husk ash-based sodium silicate. Further CSDS is analyzed using SEM, XRD, and TGA-DSC to explain its physicochemical properties. The calcium exchange capacity evaluation is carried out and is found to be 420 mg eq. CaCO3/gram of CSDS which is higher than STPP and Zeolite 4A. In this study, detergent formulations made with CSDS as a detergent builder were compared with those of STPP and Zeolite 4A to evaluate detergent performances according to the IS 4955:2020 standard.

A multi-scale method for the study of deep drying of ethylene with 3A zeolite

Coal-based ethanol to ethylene (ETE) is an emerging production pathway with the advantages of a short construction period, high product purity, and few by-products. N2 is commonly used in industry to regenerate zeolites during the ETE process, with the problems of excessive material consumption, energy consumption and environmental pollution. To solve this problem, this paper proposed a method of using the ethylene product as regeneration gas to regenerate the zeolite and recover the desorbed gas. In this work, we adopted a multi-scale simulation method combining microscale apparent diffusivity and macroscale mass transfer models. Reactive force field and molecular dynamics (ReaxFF-MD) were used to obtain an equation for the diffusion coefficient versus temperature. The start-up of the twin-tower temperature and pressure swing adsorption (TPSA) process was simulated using Computational Fluid Dynamics (CFD). The TPSA process achieved an outlet water content below 5 ppm, fulfilling the process specifications.

Clean-up of wastewater discharged from zinc industry through application of zeolite 4A produced from a waste contaminated by lubricant oil components

The zeolite 4 A powders were sustainably derived from clay-based waste contaminated with the spent lubricant oil. Then, the products were used to treat the wastewater discharged from a local zinc industry. The main challenge is removal of toxic organic components from the waste and conversion of obtained precursor to the zeolite structure, simultaneously. The variation in crystallinity was studied as a function of composition, fusion temperature, aging, and recrystallization times. The zinc adsorption was found to be markedly dependent not only on sodium carbonate/waste ratio but also on aluminum hydroxide content. However, pronounced adsorption was observed over the particles fabricated through the fusion at 900 °C. The relative crystallinity, ∼32 %, is crucial for the effective immobilization of heavy metal ions like Cd2+, Ni2+, and Zn2+ from the wastewater. This level of crystallinity is achievable with the control of aging and recrystallization times, both in 3 h. The maximal zinc adsorption capacity, ∼143 mg g−1, was obtained for the particles with large pores, 48 nm, facilitating the ion diffusion into the adsorbent. On the other hand, the appropriate electrical charge surface expressed based on zeta potential, −43 mV, provided a proper condition for the electrostatic adsorption.

Re-examination of the intumescence mechanism of fire retarded PP with APP/pentaerythritol/zeolite-4A using advanced spectroscopic techniques

The mixture of ammonium polyphosphate (APP) and pentaerythritol (PER) is a very efficient flame retardant (FR) intumescent system suitable for polyolefins such as polypropylene (PP). The mechanisms of intumescence of this FR system in this polymer was investigated using different spectroscopic techniques including continuous wave (CW) electron paramagnetic resonance (EPR) spectroscopy and solid state nuclear magnetic resonance (NMR) technique. In this work, the intumescence mechanism of PP/APP/PER formulations with and without 4A is revisited. The intumescent system was in-depth investigated using NMR, CW EPR and pulsed EPR. The CW EPR technique confirmed that free radicals are mainly generated during the intumescence of the system between 250 and 350 °C. Thanks to the pulsed EPR and solid state NMR, it was evidenced that a key structural shift from a predominantly carbonaceous residue to a predominantly phosphorated residue. Besides, it was also evidenced that zeolite 4A totally collapses during extrusion of PP/APP/PER formulations reacting with APP to generate aluminophosphates. Then, silicophosphates are generated between 350 and 400 °C. Both alumino- and silicophosphates contribute to protect aromatic structures in the residue at high temperatures.

Research on the carbon neutralization of hot mix asphalt pavement based on life cycle assessment theory

The goal of reducing carbon emissions in the field of road engineering has become an important deployment strategy. Based on the life cycle assessment (LCA) theory, the environmental impact assessment and analysis of hot-mix asphalt pavement were carried out in this work on the basis of collecting and investigating the environmental load list data of hot-mix asphalt pavement. According to different life cycle stages, corresponding carbon neutralization schemes were proposed, and the optimal carbon neutralization schemes at different stages were obtained by simulation using queuing theory. The results showed that in the whole life cycle of hot mix asphalt pavement, the construction stage had the highest energy consumption and carbon emissions compared to the other stages, and its global warming potential (GWP) and Chinese abiotic depletion potential (CADP) were also the highest, with the greatest impact on the environment. Compared to other stages, the repair and demolition stage had the smallest contribution to the GWP and CADP evaluation indicators. In the material production stage, the ASRT 5A zeolite adsorbent had the best adsorption effect on carbon dioxide gas. The carbon emissions generated during the production phase of the neutralization material required an ASRT 5A zeolite adsorbent of about 83 kg. Michelia chapensis exhibited the best carbon dioxide purification effect compared to the other three trees during the transportation construction and maintenance disassembly phase. Michelia chapensis required a leaf area of about 28,016 m2 to neutralize the carbon dioxide emissions generated in these two stages.

Solar-driven calcination of clays for sustainable zeolite production: CO2 capture performance at ambient conditions

This study presents the environmentally sustainable synthesis of zeolites from solar-calcined kaolin and halloysite, emphasizing their application in CO2 capture due to their distinctive porous structures and chemical attributes. Expanding upon prior research that utilized solar energy for kaolin calcination, we now explore halloysite as an alternative clay mineral for zeolite production and CO2 capture. Employing a solar simulator, halloysite was calcined at temperatures ranging from 700 to 1000 °C, resulting in the synthesis of zeolites 4A and 13X via hydrothermal methods. The synthesized zeolites were characterized using X-ray diffraction (XRD), low angle XRD (LA-XRD), transmission electron microscopy (TEM), and field-emission scanning electron microscopy (FE-SEM), and Brunauer–Emmett–Teller (BET) surface area measurements. Notably, the presence of Al-Si spinel, which crystallizes at elevated solar calcination temperatures, persisted within the zeolite 13X matrix, inducing a secondary mesoporous phase. The observed hysteresis in 13X samples, rather than confirming the mesoporous character of zeolite 13X, indicates a tandem effect of mesoporous Al-Si spinel with microporous zeolite 13X, exemplifying systems known as micro/mesoporous zeolitic composites (MZCs). The correlation obtained between the interplanar distances calculated from LA-XRD and pore size distributions acquired from the BJH desorption branches highlights LA-XRD as an alternative analysis method for assessing mesoporosity. While the microporosity of Al-Si spinel possessing 13X samples positively correlates with CO2 capture performance, mesoporosity appears to have minimal impact. Among the zeolites synthesized using solar energy, zeolite 4A (LTA) demonstrates superior CO2 capture capability, achieving an adsorption capacity of 2.15 mmol/g at 25 °C and 1 bar. This study highlights the potential of solar energy in producing eco-friendly zeolites from kaolin and halloysite for improved CO2 capture, advancing sustainable environmental solutions.

Simulation and experimental demonstration of helium purification from He/N2 mixtures by pressure swing adsorption

Terrestrial helium is an indispensable non-renewable resource used in medicine, space, electronics, and nuclear research. This paper reports a high-pressure five-step pressure swing adsorption (PSA) cycle using Zeolite 5A for purification of He from dilute He/N2 mixtures. A Dual-Site Langmuir (DSL) model fitted both the low-pressure N2 and high-pressure N2 isotherm data. Dynamic column breakthrough (DCB) experiments were used to confirm volumetric equilibrium loadings. The DCB model predicted the experimental breakthrough curves for a wide range of feed compositions (100% N2, 74.5% N2, and 51.5% N2) and feed pressures (1 bar and 11.2 bar). A large experimental campaign studied the impact of various operating conditions on the He purity and recovery achievable from the PSA process. The study showed that a single-stage PSA experiment could enrich He up to 13% purity with greater than 90% recovery from a feed containing 1% He. Helium purity of 95% and a recovery of 90% can be achieved from a feed containing 10% He. All trends were predicted well by numerical simulations. A multi-objective optimization was performed to maximize helium purity and recovery for various He feed compositions. The study also showed that points from the Pareto curve can be realized experimentally.

Inhibition of efflorescence for fly ash-slag-steel slag based geopolymer: Pore network optimization and free alkali stabilization

The efflorescence problem is always an intractable problem for geopolymer. Silica fume (SF), nano-silica (NS), 5A zeolite (ZL) and nano-silica treated with silane (NST), were used to mitigate the efflorescence of fly ash (FA) - granulated blast furnace slag (GBFS) - steel slag (SS) based geopolymer. The effect of their dosages on the efflorescence was evaluated through accelerated efflorescing, leaching and unconfined compressive strength (UCS) tests. The inhibition mechanisms were explored by XRD, SEM, FTIR and MIP characterization. It revealed that SF and NS presented the most effective mitigating effect on efflorescence, with 9 % of SF and 2 % of NS totally inhibiting efflorescence and improving the compressive strength, and ZL and NST also alleviated the efflorescence at appropriate contents. Optimizing pore network and stabilizing free alkali were found to be the most important aspects for inhibiting efflorescence. The SF and NS worked efficiently in both two ways, which contained a large amount of dissolvable silicate that reacted with the excessive alkali to form C(N)-A-S-H and C-S-H gels. This filled and reduced the pores from 26 nm to less than 10 nm, and stabilized alkali with reduce the free w(Na+) by more than 50.45 %. On the other hand, ZL can solidify free alkali through the ion exchange property and fill pores due to its microaggregate nature, and NST reduced the efflorescence through blocking free alkali migration paths by hydrophobicity of the pores. These findings would guide the selection of appropriate methods to solve the efflorescence problem of geopolymers.

Comparative study on dehydration of isopropanol and acetonitrile by pervaporation using PEBA/PANI/zeolite mixed matrix membranes

ABSTRACT Isopropanol (IPA) and Acetonitrile (ACN) solvents form azeotrope with water and separation by conventional processes is energy intensive. So, Pervaporation (PV) process became quite prominent and an alternative technique for dehydration of azeotropic mixtures. The selection of membrane places a crucial role in pervaporative separation and Mixed Matrix Membranes (MMMs) were widely employed. In this context, MMMs designated as PEBA-PANI and PEBA-PANI-4A were prepared by embedding PANI, zeolite 4A fillers in PEBA matrix. The synthesised zeolite particles, pristine PEBA and MMMs were characterised by XRD, FTIR, as well as contact angle measurements. Further, surface morphology and average particle size of zeolite particles are observed using SEM. Sorption studies with varying composition of isopropanol, and acetonitrile aqueous mixtures were correlated with their PV performances. The PEBA-PANI-4A MMMs showed higher % sorption of 11.34 and 8.57 for IPA–Water and ACN–Water systems respectively. Similarly greater pervaporation flux and selectivity of 0.28 kg/m2h and 720 were obtained for IPA–Water and 0.068 kg/m2h and 564 for ACN–Water systems at 10 wt. % water concentration. The PV results revealed that the MMMs exhibited better performance than pristine PEBA. All three membranes showed greater sorption, flux and selectivity for IPA-Water system than ACN-Water system.

Synthesis of magnetic 4A zeolite and its performance on ammonia nitrogen adsorption in water

Synthesis of magnetic 4A zeolite and its performance on ammonia nitrogen adsorption in water

Study and characterization of zeolites for the removal of artificial radionuclides in wastewater samples from nuclear power plants

4A, 13X, phillipsite and chabazite zeolites have been characterized regarding their capacity to remove Cs+ and Co2+ ions from aqueous solutions. The aim is to simulate the decontamination process of radioactive wastewater, originating from the former Garigliano nuclear plant in Italy, which is contaminated with 137Cs and 60Co. The four zeolites, in powder state, have been tested with solutions containing cesium nitrate and cobalt nitrate hexahydrate, in both individual and combined configurations, at different solid/liquid ratios. The Cs+ and Co2+ concentrations have been monitored over time by inductively coupled plasma (ICP) spectrometry. The results demonstrate the high efficacy of 13X zeolite providing almost 100 % of removal of both elements in a relatively short time (20–30 min). These findings are the basis for the kinetic characterization of the zeolite using radioactive solutions and, hence, for the setup of an in-situ pre-pilot plant to carry out tests with contaminated wastewater at the Garigliano facility. 13X zeolite presents a promising alternative for decommissioning radioactive wastewater.

Examination of the use of binderless zeolite blend as backfill materials to enhance CO2 adsorption in coal mine working face

The release and accumulation of CO2 in the working face of the coal mine is a major safety concern and requires an effective means to avoid the incidence of the mine. This present study therefore sought to develop a self-CO2 adsorbing backfill (SCAB) material to remove CO2 from the working environment, and simultaneously mitigate the movements of the surrounding rock layers. SCAB was formulated using coal mine solid waste activated with an alkali activator, and binderless 4 A zeolite was embedded in the backfill body. The total CO2 adsorption capacity was investigated using a CO2 flow-through method under ambient pressure and temperature conditions. The adsorption plateau was found in stages II and III respecting the predetermined curing time and zeolite contents. The maximum adsorption capacity was 143.8 mg-CO2/g-SCAB, resulting in an increase of up to 82 % in UCS compared to reference samples. The underlying mechanism was discovered in morphological analyses.1) The well distribution of zeolite in the SCAB body provided as diffusive pathways and adsorption sites for CO2 after standard curing. 2) The adsorbed CO2 underwent a desorption stage when the CO2 concentration decreased and reacted to the cementitious matrix of the SCAB body. 3) More CaCO3 crystals were generated and filled in the micro spaces of the SCAB body, which contributed to an increase in compressive strength. This study developed an effective approach to remove CO2 gas from the working face of the coal mine during backfilling. Adsorbed CO2 improved the strength of the material, provided as a novel multi-function backfill mining for sustainable green coal mining technology.

Temperature-regulated gas adsorption on LTA zeolites: Observation of sorption isotherms for methane, hydrogen, nitrogen and carbon dioxide

Temperature-regulated gas adsorption of various zeolite LTAs with different cations of Cs2+, K+, Na+, and Ca2+ (namely, Cs-A, 3A, 4A, and 5A) was analysed in the presence of different gas molecules of H2, CO2, N2, and CH4 for pressures up to 800 kPa and temperatures ranging from 77.15 to 363.15 K. Over the range of test conditions, zeolite 5A (containing Ca2+ cations) exhibited the highest uptake at 800 kPa for CO2, H2, CH4, and N2, with capacity values of 5.69 mmol.g−1, 1.14 mmol.g−1, 6.60 mmol.g−1, and 6.10 mmol.g−1, at 298.15 K and 201.15 K respectively. Zeolite 4A (containing Na+ cations) exhibited 0.74 mmol.g−1 for H2 adsorption at 201.15 K, and 800 kPa. In contrast, pores were inaccessible to H2 on ion-exchange Cs-A zeolite at a temperature range of 77.15–343.15 K, due to larger cation Cs2+ (CsA) comparison with Na+ (4A). Interestingly, zeolite 3A (containing K+ cations) showed a negligible capacity for the larger gas molecules, CH4 and N2, ascribed to the pore space blocked by the larger K+ cations (relative to the smaller Na+ and Ca2+ cations). Zeolite 3A exhibited a temperature-dependent behaviour (i.e., presumably a “trapdoor” effect) with H2 wherein adsorption was negligible at 77.15 K, but was significant above approximately 200 K. For N2, zeolite 4A exhibits similar temperature-regulated adsorption characteristics (i.e., presumably a “trapdoor” mechanism as well). These zeolite materials used in various temperature swing processes could be particularly beneficial in natural hydrogen production (with H2/N2 separation with 3A), the production of synthetic fuels from CO2/H2 mixtures (with both 3A and 4A), CO2 capture from waste streams, and applications for H2/N2 separation.

Design and characterisation of activated magnetic zeolite 4A from naturally occurring kaolin clay of Cameroonian origin for optimised dye removal by Fenton-like degradation

ABSTRACT The transformation of local clay material of Cameroonian origin into magnetic zeolite (Fe@Zeo-4A) for the degradation of acid-blue 90 in solution was investigate herein. The insertion of magnetic iron oxide particles into the zeolitic framework of Zeo-4A was achieved via hydrothermal synthesis. FT-IR spectroscopy, XRD and SEM confirmed the transformation of the clay into zeolite while EDX analysis and elemental mappings confirmed the presence of iron in the magnetic zeolite. Fe@Zeo-4A was strongly attracted to an external magnetic field. N2 adsorption-desorption studies revealed a considerable decrease in specific surface area and pore volume from the zeolite to the magnetic zeolite, suggesting the occupation of the pores of the zeolite by magnetite. The central composite design of the response surface methodology was used as optimisation approach for four parameters affecting the efficiency of degradation: solution pH, H2O2 concentration, initial dye concentration and time of stirring. ANOVA results revealed good correlation between the experimental and predicted results as well as the suitability of the linear regression model for describing the dye degradation process. An adjusted correlation coefficient of 85.17% was obtained for the dye degradation model. An optimal degradation percentage of 95.2% was obtained experimentally under optimal conditions of 7.6 for pH, 20 mg/L for dye concentration, 15.0 mol/L for [H2O2] and 15 min for time, in close agreement with a theoretical response of 96.6% predicted by the model. The magnetic zeolite was found to exhibit good stability over a wide pH range and lost only about 18% of its catalytic efficiency after five cycles of degradation experiments. Therefore, the novel magnetic zeolite-based material is an efficient Fenton catalyst for treating dye-contaminated wastewater.

Capitalizing on the Iodometric Reaction for Energetic Aqueous Energy Storage.

Iodometric and iodimetric titrations represent a prevailing technique to determine the concentration of Cu2+ ions in aqueous solutions; However, their utilization in electrochemical energy storage has been overlooked due to the poor reversibility between CuI and Cu2+ related to the shuttling effect of I3- species. In this work, we developed a 4A zeolite separator capable of suppressing the free shuttling of I3- ions, thus achieving a record-high capacity retention of 95.7% upon 600 cycles. Theoretical and experimental studies reveal that the negatively charged zeolite can effectively impede the approach and penetration of I3- ions, as a result of electrostatic interaction between them. To explore the practical potential, a hybrid cell of Zn∥I2 consisting of Cu2+ redox agent has been assembled with a discharge capacity of 356 mA h g-1. The cell affords a specific energy of 443 W h kg-1 based on I2, or 193 W h kg-1 based on both electrodes. This work offers insight on the energy utilization of the iodometric reactions and advocates a Cu2+-mediated cell design that could potentially double the capacity and energy of conventional aqueous battery systems.