Zeolite Exchange Research Articles

Metal-free β zeolite used as an efficient NH3-SCR catalyst can achieve complete immunity to SO2: Unique design strategy of sulfur-resistant catalyst

Sulfur oxides present in flue gas can deactivate metal oxide catalysts or metal cation exchange zeolite catalysts used in NH3-SCR, as the deposition of (NH4)2SO4/NH4HSO4 and metal sulfate can obstruct and damage active sites, respectively. The physical poisoning of the (NH4)2SO4/NH4HSO4 deposition can be prevented by selecting an appropriate reaction temperature range (reversible), while chemical poisoning caused by the sulfation of active sites is challenging to avoid and can permanently deactivate the catalyst (irreversible). This research addresses the issue of irreversible catalyst deactivation resulting from sulfur poisoning by employing metal-free β zeolite without redox sites, which effectively prevents redox site sulfation at its source and shields the catalyst from physical poisoning by operating at moderate to high temperatures. This metal-free β zeolite with an appropriate pore structure exhibited exceptional deNOx activity, N2 selectivity, stability, and sulfur resistance at 300 °C. The NO oxidation experiment and DFT analysis demonstrated that the specific pore structure of β zeolite functioned as a sub-nano reactor, facilitating the oxidation of NO to NO2, thereby triggering the subsequent series catalytic reaction of “fast” SCR. Even in an atmosphere with a high concentration of 300 ppm SO2, the β zeolite catalyst maintained over 80 % NOx conversion after 130 h. The slight reduction in activity was attributable to the inhibitory influence of SO2 on the collision reaction between NO and O2; however, SO2 did not have any poisonous impact on the catalyst. The unique design strategy found in present work provides valuable insights for the sulfur resistance of metal-free zeolites used in NH3-SCR process, and provides a new idea for the design of completely sulfur-resistant catalysts.

Incorporating solvent effects in DFT: insights from cation exchange in faujasites.

Zeolites are versatile materials renowned for their extra-framework cation exchange capabilities, with applications spanning diverse fields, including nuclear waste treatment. While detailed experimental characterization offers valuable insight, density functional theory (DFT) proves particularly adept at investigating ion exchange in zeolites, owing to its atomic and electronic resolution. However, the prevalent occurrence of zeolitic ion exchange in aqueous environments poses a challenge to conventional DFT modeling, traditionally conducted in a vacuum. This study seeks to enhance zeolite modeling by systematically evaluating predictive differences across varying degrees of aqueous solvent inclusion. Specifically focusing on monovalent cation exchange in Na-X zeolites, we explore diverse modeling approaches. These range from simple dehydrated systems (representing bare reference states in vacuum) to more sophisticated models that incorporate aqueous solvent effects through explicit water molecules and/or a dielectric medium. Through comparative analysis of DFT and semi-empirical DFT approaches, along with their validation against experimental results, our findings underscore the necessity to concurrently consider explicit and implicit solvent effects for accurate prediction of zeolitic ionic exchange.

In Ukrainian

The adsorption and direct calorimetric studies of the binary exchange of Ca2+ and Sr2+ cations on the Na-form of low-silica type natural clinoptilolite (Sokyrnytsya, Ukraine) were performed. The ion exchange of Ca2+ and Sr2+ cations on the Na-form of natural clinoptilolite was studied under static conditions at a solid to liquid phase ratio of 1 : 100 and a constant ionic strength of the solution of 0.1. The integral heats of ion exchange for these systems were measured using a highly sensitive Tian-Calve microcalorimeter in a special lab-made cell. Also, the ion exchange isotherms and Kielland curves were plotted, and the corrected selectivity coefficients and ion exchange constants were calculated. Changes in the integrated Gibbs free energies, enthalpies, and entropies of the ion exchange of Ca2+ and Sr2+ cations on the Na-form of clinoptilolite were calculated in entire range of the substitutions of the exchange complex. The thermodynamic parameters of incomplete ion exchange were analyzed in terms of the crystal structure of the zeolite. In addition, the state of exchangeable cations in the channels of clinoptilolite was described in detail. It is shown that structural heterogeneities of cation-substituted forms of clinoptilolite are clearly reflected in the dependence of thermodynamic functions on the degree of exchange, and significant differences are observed between the exchange of Ca2+ and Sr2+ cations that could not be described by standard thermodynamic values. Although the isotherms of ion exchange have a convex shape, the Na-form of clinoptilolite does not show any thermodynamic affinity to Ca2+ cations. This ion exchange reaction is accompanied by positive enthalpy changes in all range of substitutions of the exchange complex. At the same time, thermodynamic selectivity toward Sr2+ cations was observed for 40 % of the zeolite exchange centers, and the exchange is accompanied by minor exothermic effects in the range of small substitutions, and the ion exchange isotherm has σ-like form. In general, the thermodynamic affinity of the Na-form of clinoptilolite to the studied metal ions under conditions of incomplete exchange is ordered as following hydration energy trends in the case of the lyotropic properties among alkaline earth metals. Thus, the experimental thermodynamic characteristics of ion exchange equilibria could be a reliable support for the practical using of natural clinoptilolite.

Probing diffusional exchange in mesoporous zeolite by NMR diffusion and relaxation methods

We propose NMR relaxation techniques to evaluate diffusional exchange between the different porosity compartments of heterogeneous catalyst extrudates in addition to NMR diffusion measurements. The two systems considered are close to industrial products and contain a wide distribution of pore sizes spanning from microporosity (2 types of zeolites CBV400 and CBV720), mesoporosity induced by the alumina binder, and macroporosity introduced during the shaping procedure. The question is to determine in which system the meso and macroporosity provide the best access to microporosity. Beside standard techniques, we measured the pore size distribution using NMR cryoporometry in the range 2 nm up to 1 μm, and the amount of microporosity below 2 nm from relaxation data at −29 °C. These measurements provide reference values independently of the connectivity or the hierarchical organization of the pore network. Long range diffusion was measured using methane and cyclohexane to evaluate the effect of macropores. When saturated with squalane, the diffusive exchange between micro and mesoporosity was evaluated using two techniques: (i) the comparison of the apparent mesoporosity fraction in the T2 distribution to the true value measured by cryoporometry, (ii) the measurement of exchange times using T2-exchange-T2 experiments. These two approaches give coherent results. The diffusive coupling was also observed with 2-propanol saturated extrudates, for which the surface residence time τS was evaluated from the interpretation of the 3 relaxation times T2, T1 and T1ρ; for the 2 samples τS differ by 2 orders of magnitude due to the very different Si/Al ratio of the 2 zeolites used in the extrudates. All these methods lead to the conclusion that the presence of mesoporosity in zeolite crystals is beneficial to the diffusive transport with the surrounding porosity only when molecule/zeolite interactions are not predominant.

Processing renewable and waste-based feedstocks with fluid catalytic cracking: Impact on catalytic performance and considerations for improved catalyst design.

Refiners around the globe are either considering or are actively replacing a portion of their crude oil inputs originating from fossil sources with alternative sources, including recycled materials (plastics, urban waste, mixed solid waste) and renewable materials (bio-mass waste, vegetable oils). In this paper, we explore such replacement, specifically focusing on the fluid catalytic cracking (FCC) operation. Five pyrolysis oils, obtained from municipal solid waste (MSW) and biogenic material (olive stones/pits), were fully characterized and tested at 10% loading against a standard fluid catalytic cracking (FCC) vacuum gasoil (VGO) feed in a bench scale reactor using an industrially available fluid catalytic cracking catalyst based on ultrastable Y zeolite to simulate fluid catalytic cracking co-processing. Despite having unique feed properties, including high Conradson carbon (e.g., up to 19.41wt%), water (e.g., up to 5.7wt%), and contaminants (e.g., up to 227ppm Cl) in some cases, the five pyrolysis oils gave similar yield patterns as vacuum gasoil. Gasoline was slightly (ca. 1wt%) higher in all cases and LPG slightly (ca. 1wt%) lower. Olefinicity in the LPG streams were unchanged, bottoms and light cycle oil (LCO) showed no significant changes, while dry gas was slightly (up to -0.2wt%) lower. Coke selectivity was also unchanged (maximum -7.7wt%, relatively), suggesting minimal to no heat balance concerns when co-processing in an industrial fluid catalytic cracking unit. The results demonstrate the applicability of municipal solid waste and biogenic originating pyrolysis oils into a refinery. A catalyst design concept is explored, based on higher rare Earth oxide exchange and/or utilization of ZSM-5 zeolite, that would further minimize the impacts of replacing fossil oils with pyrolysis oils, namely one that shifts the 1% higher gasoline into LPG.

Ordered Heteroatom Siting Preserved by B/Al Exchange in Zeolites

Ordered Heteroatom Siting Preserved by B/Al Exchange in Zeolites

Investigation on the influence of modified zeolite molecular sieve on the hydrocarbon adsorbent and adsorption performance during cold-start conditions based on Monte Carlo simulation and grey relational analysis

To discover adsorbents with promising adsorption capability for hydrocarbon catcher, this study numerically investigated the adsorption process of modified MOR, MFI, and CON zeolites utilized in hydrocarbon catcher of hydrocarbon (HC) molecules for hydrocarbon emission control during cold-start. Ethylene (C2H4) and benzene (C6H6) were used as probe molecules in the single-component adsorption simulation. The mixture of methane (CH4), C2H4, propylene (C3H6), propane (C3H8), water (H2O) and C6H6 was used as adsorbate in the multicomponent adsorption simulation. The Grand Canonical Monte Carlo (MC) method was used in the adsorption simulation. Grey Relational Analysis (GRA) method was used to determine the influence degree of zeolite molecular sieve type and environmental conditions on the adsorption capacity of hydrocarbons. The adsorption isotherms of hydrocarbon single component and multicomponent molecules on different silicon-aluminum (Si/Al) ratios and different ion exchange zeolites were studied at various low temperatures and pressures. Results of adsorption simulation present that the best adsorption effect on C2H4 was obtained for the magnesium ion (Mg2+) modified MFI molecular sieve at a Si/Al ratio of 3. The adsorption of C6H6 was better for the Na+ modified molecular sieve at Si/Al ratios of 15 and 7. Mg2+ modified MOR molecular sieve can be given priority when the overall control of hydrocarbon mixture content is required, which has adsorption for all kinds of hydrocarbon molecules and more uniform adsorption performance. The calcium ion (Ca2+) modified MFI molecular sieve is suitable for the condition when exhaust gas contains more C3H6, while Mg2+ modified MFI molecular sieve can be used when there are more C3H8. In GRA, the factors with the greatest influence on the adsorption of the C2H4 component are the type of molecular sieve and the porosity. The most important factors on the adsorption of the C6H6 component are the molecular sieve type and temperature, followed by the porosity. In the adsorption of multicomponent hydrocarbons, porosity has the greatest effect on the adsorption amount, followed by molecular sieve type and Si/Al ratio. In addition, the total adsorption of hydrocarbon molecules will be increased with the Si/Al ratio of the molecular sieve.

Catalytic and Mechanistic Insights into Side‐Chain Alkenylation of Toluene with Methanol for Styrene Formation

AbstractThe literature on catalytic and mechanistic aspects of the side‐chain alkenylation of toluene with methanol for the formation of styrene on solid base catalysts is reviewed. The development of catalysts and catalysis are described mostly on alkali ion exchange zeolite catalysts with fundamental chemistry related to the side‐chain alkenylation. Mechanistic studies performed from various viewpoints are described. Methods to elucidate the reaction mechanisms are discussed based on the identification of the adsorbed species of the reactants, use of plausible intermediate compounds as reactant, characterization of surface properties to examine the correlation with reaction results, poisoning of the active sites by certain molecules, and theoretical calculations of the energy profile along with the reaction coordinate. These studies are discussed with critical assessments. The review addresses several challenges that prevent the side‐chain alkenylation of toluene with methanol from industrialization which include decomposition of methanol to CO and H2, and co‐production of ethylbenzene. The paper covers mostly literature published during the period from 2000 to early 2021.

Structure stabilization of zeolite Y induced by yttrium and its role in promoting n-docosane conversion

Rare earth (RE)-exchanged zeolite Y is the major active component of fluid catalytic cracking (FCC) catalysts. Herein, a series of yttrium (Y3+)-exchanged zeolites Y was prepared by the ion-exchange method, and the location of Y3+ ions in the Y3+-exchange zeolite NaY was determined by fitting synchrotron radiation X-ray powder diffraction (XRPD) pattern combined with the infrared spectra in the hydroxyl stretching region. In analogy to lanthanum (La3+)-exchanged zeolite Y, Y3+ ions were preferentially located inside the sodalite units near the double six-membered rings (D6R's), octahedrally coordinating to three framework oxygens and to three H2O molecules (or OH groups) in close proximity. The substitution of Y3+ ions for counter-ions Na + caused a noticeable shrinkage of the unit cell due mainly to the relatively small ionic radius and high charge density of Y3+ ions. As a consequence, the Y3+-exchanged HY-based FCC catalyst exhibited improved steam stability, and higher selectivity for high-value products (liquefied petroleum gas and C5+gasoline) in n-docosane cracking compared with the La3+-exchanged HY-based catalyst.

Evaluation and Comparison of Antimicrobial Properties of Natural and Synthetic Zeolites Exchanged with Silver, Zinc, Copper and Nickel Ions

Zeolites are high-porous active crystalline biomaterials. Recently many studies have been done on their antibacterial properties especially on zeolites exchanged with metallic cations. In this paper, we investigate the effective factors on the antimicrobial activity of natural and synthetic zeolites exchanged with silver, zinc, copper nickel, and bromide cations. This study reviews the published articles on the antibacterial properties of the natural and synthetic pure zeolites as well as the ion exchange ones. The results of our investigation show that ion exchange zeolites exhibit a very good antibacterial effects even in comparison with other conventional antibacterial materials. The strongest antibacterial activity was reported in silver exchanged zeolites against Bacillus cereus and Escherichia coli with MIC of 16 μg/ml. According to the results reported derived from different articles, it can be concluded that zeolites with biocompatibility and high ion exchange capacity can be used as efficient antibacterial materials. Pure zeolites have antibacterial activity at high concentrations, whereas all synthetic and natural zeolites exchanged with metal cations investigated in this paper exhibit good antibacterial activity at very low concentrations generally due to sustained and prolong release of metal cations.

Oxidative dehydrogenation of n-octane using Ba and Ga-modified faujasite type catalysts prepared by different methods

Ionic exchange and isomorphic substitution were used for the synthesis and modification of faujasite (zeolite and silicalite Y) catalysts. These two methods were used to synthesize 1 wt% extra-framework and framework gallium modified faujasite zeolites respectively, with a Si/M ratio of 2.6, where M = Al and/or Ga. For the silicalite catalyst, 3.5 wt% of Ga was used to maintain the Si/Ga ratio. A series of BaY, Ga-BaY(IS) and Ga-BaY(Sil) were prepared by isomorphic substitution, where (IS) and (Sil) represent Isomorphic Substitution and Silicalite respectively. Ga-BaY(IE) and BaGa-NaY(IE), were prepared by ionic exchange (IE) using the synthesised BaY and a commercial NaY for the latter. For all the prepared catalysts, barium was kept constant at about 4.2 wt% except for BaGa-NaY(IE), where Ba was 1.4 wt%. For the sodium containing catalysts, Na was 10.3 wt%. Pyridine IR and chemisorption techniques showed that the catalysts prepared had more Lewis acid sites compared to Bronsted acid sites. The Na containing zeolite had the highest total acidity compared to those containing only Ba. Aluminium free silicalite contained the least total acidity, which is consistent with previous studies. Catalytic data at iso-conversion (7 ± 1%) showed that the Ba incorporated by ionic exchange zeolites and the silicalite were more selective to octenes (36 and 33% respectively) and less selective to COx (35 and 33% respectively) compared to the isomorphically substituted Ba catalysts. Selectivity to cracked products was reduced when aluminium, responsible for the strong Bronsted acid sites, was eliminated from the synthesis.

Antimicrobial Properties of Knit made with PET and Ion Exchange Zeolite Nanocomposite Spun Yarn

Antimicrobial Properties of Knit made with PET and Ion Exchange Zeolite Nanocomposite Spun Yarn

Sorption of Heavy Metal Ions of Chromium, Manganese, Selenium, Nickel, Cobalt, Iron from Aqueous Acidic Solutions in Batch and Dynamic Conditions on Natural and Synthetic Aluminosilicate Sorbents.

Zeolites are materials with known sorption properties. The sorption is thought to progress mainly by ion exchange with Na+, K+, Mg2+, Ca2+ or H+ from the zeolite exchange sites. The aim of the study was to compare the sorption properties of natural and synthetic zeolites on the example of the removal of selected metals from aqueous acidic solutions. Uptake experiments for selected ions of chromium, manganese, selenium, nickel, cobalt, and iron were performed using the batch and kinetic column methods. The sorption of the individual metal ions in mg per 1g of sorbent was determined for each sorbent. The relative affinity sequence of the examined cations toward the various sorbent was presented. The Langmuir model was used to model the adsorption equilibrium. Vermiculite under 1 mm of diameter (SF), Na-X, and Na-A were proved to be the most suitable for the individual uptake of studied metal ions. It was observed that the behavior of selenium ions differed from the remaining ones which was interpreted that selenium undergoes adsorption in the anionic form. The fixed-bed column studies were performed using Na-A, ensuring the sorption of selenium in the presence of iron(III) ions. The experiments were conducted using Na-X zeolite pre-loaded by Fe(III) as well as unmodified sorbent eluted by an equimolar mixture containing 100 ppm of Fe and Se. Obtained results prove that selenium sorption improves if other metal ions such as iron appear in the acidic solution. That efficient selenium sorption conditions can be applied to remove selenium which was recognized as toxic at higher levels.

Observation of La-exchanged NaY zeolite using aberration-corrected scanning transmission electron microscopy

The determination of metal location in zeolite and an estimation of site occupancy by using spherical aberration-corrected scanning transmission electron microscopy ( Cs -corrected STEM) were attempted through the observation of La-exchanged NaY zeolite (LaNaY). LaNaY was prepared by the ion exchange of NaY zeolite and observed using high-angle annular dark-field (HAADF)-STEM. Simultaneous imaging of both the zeolite framework and La atomic columns revealed the La positions to be in sites I and I’. From the averaged HAADF intensity of each La site, the La occupancy was estimated to be about a fourth for both sites I and I’. The estimated La occupancy of site I was much larger than that measured by XRD, suggesting that the STEM data reflects the highly dehydrated state of LaNaY. In addition, methods for observation of individual La atoms are described. • La atoms and T-sites in La-exchanged NaY zeolite were simultaneously visualized. • The locations of La atoms were determined, and the La site occupancy was estimated. • Methods for observing individual La atoms were described.

Biological reconditioning of sodium enriched zeolite by halophytes: case study of dairy farm effluent treatment

Constructed wetlands (CW) containing clinoptilolite zeolite and planted with five halophytes (Sesvium portulacastrum, Juncus effusus, Suaeda monoica, Inula crithmoides and Sarcocornia fruticosa) were irrigated with treated dairy farm effluent. The CW were operated for two years with retention time ranging from 2 to 7 d. Plant species did not affect SAR which was reduced in all treatments from 4.85 to 2.59 (mmol/L)0.5 due to ion exchange in zeolite. Halophytes increased evapotranspiration to 30 mm d−1 which countered sodium removal. Zeolite planted with Sesuvium portulacastrum had 15% lower sodium percentage (ESP, F1,118 = 12.53, p = 0.0006) and 5% higher calcium percentage (F1,118 = 7.44, p = 0.007) compared to non-planted zeolite, indicating reconditioning of zeolite with respect to sodium. Enhancement of SAR removal capability by reconditioned zeolite was demonstrated in 24 h batch experiments on excavated zeolite (n = 6) with saline water (SAR = 0, 17.6, 62.8, and 122.8 (mmol/L)0.5). Zeolite from Sesuvium planted CW reduced SAR to a greater extent than non-planted zeolite and was significant for inlet SAR 17.6 which was reduced to 3.33 ± 0.3 (mmol/L)0.5 compared to 3.68 ± 0.12 by non-planted zeolite (p < 0.05). In-situ biological reconditioning of active matrix in CW by tailored macrophytes is a novel strategy that may be applicable to other pollutants.

The influence of ion exchange in zeolite X on the properties of phenol-formaldehyde composites

This work focused on the influence of ion exchange in the zeolite X structure on the properties of composites with phenol-formaldehyde resin. Four types of zeolites X with mono and divalent cations were prepared and used as fillers in phenolic composites. The results obtained using energy dispersive spectrometry confirm the effectiveness of ion exchange. Analysis of materials with several techniques indicates no differences between individual zeolites. The influence of ion exchange is visible only in the parameters determined by inverse gas chromatography. The ability for dispersive and acid-base interactions described by these parameters is significantly different for zeolites with monovalent cations than divalent cations: generally, zeolites with monovalent cations are characterized by more active surfaces and higher acidity. The material with the highest flexural strength was the composite with the sodium form of zeolite. The influence of cation type on cross-linking and thermal stability of phenolic composites was also noted.

МОДИФІКУВАННЯ ТЕРМІЧНО АКТИВОВАНОГО ПРИРОДНОГО КЛИНОПТИЛОЛІТУ ЙОНАМИ АРГЕНТУМУ

The analysis of the areas of application of natural zeolite – clinoptilolite is carried out. In particular, it is used as a sorbent with cation-exchange properties in the purification of natural and waste waters from non-ferrous and heavy metals, radionuclides and other harmful components of water. The prospects of modifying clinoptilolite with silver ions are shown. These ions give it antibacterial properties, which significantly expands the scope of its application. The scheme, as well as a description of laboratory unit and the methodology for carrying out studies related to dehydration as thermal activation and modification of natural clinoptilolite with silver ions, are presented. The results of zeolite dehydration in the temperature range of 100 ... 400 °C, as well as due to the action of electromagnetic radiation of the microwave range, are presented and analyzed. The speed of the process and the degree of thermal and electromagnetic dehydration of clinoptilolite are determined. It is shown that, under the influence of electromagnetic oscillations, the degree of dehydration corresponds to thermal activation at a temperature of 120 °C, however, the temperature of the mineral rises at this by no more than 2 degrees. It is found that thermal activation contributes to an increase in the sorption capacity of clinoptilolite relative to silver ions. An increase in the activation temperature leads to an increase in the rate of ion exchange, however, in the range of dehydration temperatures of 150 ... 400 °C, the equilibrium capacity of zeolite with respect to silver ions is almost the same. An increase in the temperature of modification has little effect on the rate and degree of substitution of the exchange zeolite cations with silver ions. This indicates that the modification process takes place in the intradiffusion region. The features of ion exchange in the case of initial and thermally activated samples of clinoptilolite are analyzed.

Observation of Ag Nanoparticles in/on Ag@MIL-100(Fe) Prepared Through Different Procedures.

Loading of active metals, metal clusters, and/or metal nanoparticles in Metal Organic Frameworks (MOFs) is an emergent field with applications in sensors, catalysis, medicine, and even in the polymeric industry. In the present work, MIL-100(Fe) has been synthesized and reacted with AgNO3 through liquid and incipient wetness, and also through solid-state reaction or solid grinding. The aim of this study is to evaluate whether the MIL-100 would uptake metal particles using a similar principle as that of the ion exchange in zeolites, or else, their inherent humidity would favor the “dissolution” of the metal salt, thus yielding very small metal particles. The immobilization of Ag nanoparticles inside the MOF pores was identified by Cs-corrected scanning transmission electron microscopy (Cs-corrected STEM) techniques.

Propane activation on Zn-modified zeolite. The effect of the nature of Zn-species on the mechanism of H/D hydrogen exchange of the alkane with Brønsted acid sites

Zn-modified zeolites exhibit high activity for the aromatization of C2+ alkanes. To understand the effect of Zn-species of different nature on propane molecules activation and transformation, the H/D hydrogen exchange of zeolite Brønsted acid sites (BAS) with deuterated propane-d8 has been investigated. Two samples of the Zn-modified zeolite containing exclusively either isolated Zn2+ cations (Zn2+/H-BEA) or small (ZnO)n clusters (ZnO/H-BEA) have been studied. Zn-species of either type work jointly with BAS and may provide the synergy effect for propane CH bond activation resulting in dramatic acceleration of the H/D exchange between propane and BAS. The accelerating effect of isolated Zn2+ cations is more pronounced compared to zinc oxide clusters. Moreover, the H/D exchange occurs regioselectively into the methyl groups of propane on Zn2+/H-BEA zeolite. For ZnO/H-BEA, the methylene group becomes also involved in the exchange after some induction period. Various mechanisms providing the regioselective H/D exchange on Zn2+/H-BEA as well as the involvement of the methylene group after the induction period on ZnO/H-BEA are discussed.

Selective formation of linear-alpha olefins (LAOs) by CO2 hydrogenation over bimetallic Fe/Co-Y catalyst

A series of supported Fe/Co catalysts with Y zeolite-containing K, Ce or La used as support were synthesized to perform CO2 hydrogenation to linear-alpha olefins (LAOs). Medium acid-base properties and the content of active carbide (Fe5C2) are both affected by the different ion-exchange strategies and heteroatom doping used, which are crucial for the CO2 conversion to LAOs process. CO2 conversion (25.9%) and highest C4+= alkenes (45.9%), of which the formation of LAOs accounts for 78.9%, were achieved after the supported bimetallic Fe/Co-Y catalyst containing K+-exchange zeolite was used.