Zeolite Products Research Articles

The utilization of hydroxylsodalite synthesized from coal fly ash for zinc removal in acid mine drainage

One of the alternative solution to reduce ash waste in landfills is by utilizing coal fly ash for the removal of metal ion in wastewater, especially acid mine drainage (AMD). In this study, zeolite was synthesized from coal fly ash using a two-step method, hydrothermal and fusion method. The coal fly ash and the zeolite product were characterized physically and were used for the removal of Zn2+ in AMD. The adsorption experiment was carried out using batch method in synthetic AMD solution to study the influential parameters such as adsorbent dosage, contact time, adsorbent isotherms and kinetics. The zeolite synthesized in this study resulting hydroxylsodalite zeolite type, which increases the surface area. It was revealed from the adsorption experiment that the removal efficiency of Zn2+ was 93.47% under the conditions of pH ± 3, initial concentration Zn2+ 100 ppm, optimum contact time 120 minutes, and adsorbent dose 6 g/L. Furthermore, the Langmuir isotherm model and the kinetics model of pseudo-second-order fitted the adsorption data better, with the maximum sorption capacity of 27.32 mg/g. The result of this study indicate hydroxylsodalite synthesized from coal fly ash has great potential as an economical and sustainable material for the removal of metal ion Zn2+ in wastewater.

The role of alkaline activation in the structural transformations of aluminosiliceous industrial wastes towards zeolite production

The zeolitization of two selected aluminosiliceous industrial wastes, a fly ash and an exhausted Fluid Catalytic Cracking (FCC) catalyst, was studied. Solid products enriched in zeolite A were successfully synthesized by using a simple procedure consisting of waste activation by alkaline fusion followed by a hydrothermal treatment in mild conditions. During activation, it was observed that different crystalline NaAlSiO2 polymorphs could be generated, their crystallization being dependent on the operational variables used for pretreatment (temperature and time). So, the different intermediate NaAlSiO2 polymorphs obtained at temperatures of 800 °C, 830 °C and 850 °C and with calcination times of 0 h, 0.5 h, 1 h, 2 h, 4 h and 12 h were identified and their percentages were estimated by X-ray diffraction and SEM analysis. After pretreatment, two main crystalline phases, called nepheline and low-carnegieite, were formed in the activated samples, their percentage ratio depending on the activation conditions. When the treated samples were subjected to hydrothermal treatment, the nepheline phase was almost completely dissolved during the aging of the reaction mixture at ambient temperature. On the contrary, the levels of low-carnegieite in the solid phase remained insoluble after aging. During the hydrothermal treatment at 90 °C, a gradual decrease of the low-carnegieite content and a concomitant increase in zeolite A content was noted, indicating a topotactic transformation along the crystallization step. The highest zeolite A conversions were obtained by applying an alkaline fusion treatment at 800 °C for 12 h for fly ash (74%), and at 800 °C for 4 h for the exhausted catalyst (79%).

A critical review of waste resources, synthesis, and applications for Zeolite LTA

This review not only provided a summary of the state of the art with regards to commercially important zeolite LTA technology, but also identified strategies to further promote uptake of this material in industry. The hypothesis was that application of SWOT analysis principles would assimilate data regarding zeolite LTA in a manner which provided a concise and clear pathway for future development. Zeolite LTA synthesis innovation related to preparation of nano-zeolites, hierarchical materials, binderless zeolite granules, magnetized zeolites, loading of metals/metal oxides into the pore structure and introduction of heteroatoms. Waste resources included used glass, alum sludge from drinking water plants, fly ash from power stations, recycled aluminium, manufacturing waste, ash from organic material and various aluminosilicate rocks from the mining sector. In addition to traditional application of zeolite LTA for water softening opportunities; use of zeolite LTA for catalytic processes, membrane separation, alternate zeolite production, wastewater treatment, and anti-microbial purposes have been described. A key weakness identified was the lack of compelling economic models in relation to synthesis of zeolite LTA from waste resources or by new methods which produce hierarchical materials. Linked to the lack of economic studies was the limited information about process design of zeolite LTA manufacturing systems or industrial application of zeolite LTA. Key strategies developed included: (1) scaling-up of new synthesis methods to kg levels and beyond; (2) creation of process flow diagrams and piping and instrumentation diagrams; (3) detailed economic analysis of zeolite LTA synthesis from waste materials; (4) Utilization of methods to reduce the cost of zeolite manufacture such as ultrasonics, microwaves, “one pot” synthesis, continuous production and rapid synthesis; and (5) demonstration of zeolite LTA performance at pilot plant scale for the various applications identified. In conclusion, zeolite LTA has an expanded role to play in the area of zeolite science and this study has provided a roadmap to accelerate this development.

Calcined Post-Production Waste as Materials Suitable for the Hydrothermal Synthesis of Zeolites.

The zeolite production process is currently being very intensively researched. Due to environmental protection, as well as issues related to the guidelines of a zero-waste economy, all activities aimed at obtaining such materials from post-processed waste are extremely important. This article presents an innovative method of utilising calcined carboniferous shale in order to produce synthetic zeolites. The raw material for testing came from two Polish hard coal mines. Both the chemical and phase composition of the coal shale were characterised. Based on the recorded thermal analysis results coupled with the mass spectrometer, the processes occurring during the heating of raw materials were interpreted and the calcination temperatures were determined. The changes in the phase composition of raw materials resulting from the calcination process used were also analysed. The heat-treated raw materials were subjected to the synthesis of zeolites in an aqueous solution of sodium hydroxide by means of the hydrothermal method at a concentration of 2.75 M. The results of water leaching and structural parameters are presented for both raw materials, as well as the produced synthesis. The conducted research confirmed that after the application of the synthetic process on coal shale, a zeolite with a surface area of SBET equal to 172 m2/g can be obtained.

The effects of metakaolinization and fused-metakaolinization on zeolites synthesized from quartz rich natural clays

Abstract A variety of zeolites have been synthesized by performing either metakaolinization or fused-metakaolinization of natural clays prior to the hydrothermal synthesis step. To understand the differences arising from performing fused metakaolinization rather than simple metakaolinization, the calcination conditions, gel composition, gelling and crystallization conditions were kept similar for both methods. The original clay material, a kaolinite group mineral with Si/Al molar ratio of 1, had a high content of quartz as impurity. The two treatment methods gave different zeolites of high crystallinity and relatively similar Si/Al molar ratio. Zeolite Na-A with 98% crystallinity was produced from the metakaolinization method within 8 h, while Na-X with 96% crystallinity was generated from the fused-metakaolinization (fusion) method within 48 h. In the fusion method, sodalite was formed at or beyond 48 h of hydrothermal reaction, while in the metakaolinite method, apart from a slight decrease in intensities of XRD peaks, no phase change was observed even after 168 h of hydrothermal reaction. Modification of the synthesis gel by increasing the Si/Al molar ratio via addition of fumed silica resulted in mixed zeolite products via the metakaolinite method, while Na–Y was the major product for the fusion method. Except for Na-A, all zeolite products had high surface area of up to 600 m2/g and micropore volume of 0.18 cm3/g. Our findings demonstrate the crucial role of the pre-treatment step in the synthesis of zeolites from clay minerals, and that a variety of high quality zeolites are achievable via choice of pre-treatment protocols.

Sodic and Potassium Zeolites from Fly Ash Coming from Coal Combustion of Thermoelectric Termotasajero S.A.S

The fly ash (CV) of Termotasajero S.A.S, is a residue of coal combustion with high environmental impact on air, water, soil and ecosystems. They have a high content of Si and Al, which makes them an optimal by-product for the production of zeolites. The CV were sieved and leached in order to produce high purity zeolites. The synthesis was carried out by the hydrogel method in activation with alkalis of NaOH-2M and KOH-5M, crystallization of 2h and 3h respectively, at 90° C and 560 rpm. The sodium and potassium zeolites presented a Si/Al molar ration of 1.19 and 1.00 respectively, which were classified as zeolites natrosilite and zeolite K-F, according to the ray-X diffraction pattern (DRX). In the zeolitic product, the main elements were identified as Si, Al, O, Na, K, Ca, Fe, and in smaller proportions Ti and Mg, with irregular morphology of microcrystals with particle sizes less than 12 micrometers (μm). The analysis of Cationic Exchange Capability (CIC) shows the ionic capability of the material, finding that the highest value (141 meq/100g) corresponds to the zeolites activated with NaOH.

In‐situ synthesis of NaP zeolite doped with transition metals using fly ash

AbstractHere, a novel approach has been proposed to synthesize NaP zeolite adsorbents doped with transition metals (M‐NaP) using the Na2SiO3 and NaAlO2 compounds extracted from fly ash via activation and stage treatment. The preparation process of M‐NaP employed the in‐situ synthesis in combination with organic complexation method. The effects of the addition amounts and valence state of transition metals on the zeolite products were investigated. The crystalline phase, morphology, and particle size of M‐NaP were characterized using X‐ray diffractometry (XRD), Scanning electron microscopy (SEM), and Laser particle size analyzer (PSD). The doping process was investigated using X‐ray photoelectron spectroscopy (XPS) and Materials Studio. The adsorption performance of M‐NaP was tested by the adsorption of Zn2+. The optimal molar ratio of n(Al2O3)/n(M) was identified as 8:1 for Co–NaP, Ni–NaP, and Fe–NaP, compared with 6:1 for Ti–NaP. The influence of transition metals on adsorption was: Co–NaP > Ni–NaP > Ti–NaP > Fe‐NaP. Due to largest surface area of Co–NaP (162.5 m2/g, five times than that of NaP‐RAW), the maximum removal rate of Zn2+ was above 99.50% at 25°C. The existence state of transition metals in M‐NaP primarily included: isomorphous substitution and balance of the skeletal charge, with the latter in majority. The simulation of Materials Studio indicates that Si at T4 was first substituted and then, Si at T3 opposite T4 was replaced when the replacement of Si in different sites occurred.

Comparative investigation of reactivity of different kinds of fly ash in alkaline media

Comparison of the influence of temperature and different alkali activators on the reactivity of two types of fly ash (conventional, fluidized) was presented. The main emphasis was put on fluidized fly ash as potential component of binding mixtures containing low amount of cement. Conventional fly ash was used as a reference. It was found that for these materials the key differences affecting products of activation are: availability of calcium and sulfate ions as well as structure of fly ash grains influencing dissolution of aluminate and silicate species. Fluidized fly ash, contrary to conventional fly ash, undergoes reaction in 0.1 M solutions of hydroxides forming mainly ettringite. In the case of 4 M hydroxides, both fly ashes undergo hydration processes. Conventional fly ash formed mainly amorphous aluminosilicate gel, while fluidized fly ash may create zeolitic products especially in the case of elevated temperature of early hydration. Sulfate and alkali ions can be incorporated into aluminosilicate structure of new formed products; however, this process depends strictly on the type of used hydroxide and its concentration. The presence of Ca(OH)2, carbonates and alkali sulfates was also registered in the case of hydrated fluidized fly ash.

Geological aspects of processing zeolite-containing rocks in Eastern Transbaikalia

The resource-potential of zeolite-containing raw materials of Eastern Transbaikalia is estimated. The prospects of mining and processing zeolite-bearing rocks in the Priargunsky District of the Transbaikal Region are studied. The geological aspects of mining and processing of zeolite-bearing rocks in Eastern Transbaikalia are considered. The problems of integrated processing of zeolite-containing rocks are discussed. The influence of climate on the stability of natural objects under man-made impact is estimated. The ways of reducing environmental impact of zeolite production are identified.

Adsorption characteristics of a clinoptilolite-rich zeolite compound for Sr and Cs

The Sr and Cs adsorption capacities of LithoFill™, LithoGran™ and a competing clinoptilolite containing zeolite product were investigated by radioanalytical methods (85Sr and 134Cs gamma spectroscopy). The dependence of adsorption and adsorption rate on physical factors including temperature, available ions and time were assessed. In addition, the reversibility of adsorption under high ionic strength conditions was also examined. In general, cesium is more strongly adsorbed than strontium, adsorption yields are generally independent of temperature (from room temperature to 65 °C) and adsorption is relatively rapid (identical results for 2 or 5 day adsorption times). As expected, increasing the concentration of other ions in solution tends to reduce adsorption of cesium and strontium. In general, Cs adsorption ranges between 54.5 and 45.2 mg/g for LitoFill and LitoGran samples and between 36.9 and 24.4 mg/g for the competing product. For Sr adsorption, ranges are 30–21 mg/g and 7.3–6.7 mg/g respectively, leading to the conclusion that the higher content of clinoptilolite in the LitoFill/LitoGran samples results in better adsorption characteristics.

Synthesis of zeolite P1 from fly ash under solvent-free conditions for ammonium removal from water

In this work, zeolite P1 is synthesized from fluidized bed fly ash (FA) via a solvent-free process. The formation of zeolite P1 is investigated as a function of crystallization reaction time. The solid mixture of FA and Na2SiO3·9H2O with a mole ratio of Na:Al:Si = 1.5:1:1.7 can be converted to zeolite P1 at 80 °C for 24–96 h. XRF, XRD, SEM/EDS, FTIR, TG/DSC and BET techniques are used to test the properties of resultant zeolite products. The efficiencies of the resultant zeolite for ammonium adsorption are evaluated on factors including solution pH, NH4+ ions concentration, temperature and adsorption time. The kinetic data and adsorption equilibrium data fit satisfactory with the Ho's pseudo-second-order kinetic model and Langmuir model. The maximum ammonium adsorption capacity of zeolite P1 (22.9 mg/g) can be reached within 40 min at optimal pH of 6. The adsorption performance is higher than many of the natural zeolites and closely similar to the zeolites synthesized from fly ash through the conventional hydrothermal route. Our study not only provides new insights into the preparation of zeolite from fly ash, but also reveal that the zeolite P1 synthesized through solvent-free route is a promising material for ammonium removal.

A recyclable adsorbent for salinized groundwater: Dual-adsorbent desalination and potassium-exchanged zeolite production

This study focused on advancing the dual-adsorbent desalination technique that sequentially combines calcined layered double hydroxide (CLDH) and acid-treated zeolites (H-form zeolite) using groundwater spiked with potash mining effluent (brine). In sequential batch experiments, the CLDH adsorbent first reduced the high Cl− concentration (4600 mg/L) of saline groundwater by 96%, the Ca2+ by 90%, and the Mg2+ by 92%, while transiently raising the pH to 12.80. H-form zeolites preconditioned with Na+ then removed 92% of the Na+ (2010 mg/L), while neutralizing the adsorption effluent pH to 7.7 and lowering the sodium adsorption ratio (SAR; 139.6 to 6.6) and the hardness (574 to 48.4 mg/L). In comparison, an equivalent amount of unmodified zeolite removed only 51% of the Na+ and generated extremely hard water due to Ca2+ and Mg2+ release (1519 mg/L). Na+-conditioning the zeolites prior to acid treatment enhances native cation removal, forming H-form zeolites. Synchrotron-based X-ray scanning transmission microscopy (STXM) showed the occurrence of dealumination and visualized the sodium distribution associated with Si and Al sites in the H-form zeolites. Four consecutive desalination cycles were feasible for Na+ and K+ adsorption by regenerating the H-form zeolite. During regeneration, the Na+ desorbed while the K+ remained in the regenerated zeolites. Cumulative K+ loading in the regenerated zeolites increased from 4.8 to 21.2 mg/g, producing K-form zeolites. These K-form zeolites released K+ (2.15 mg/L for 24 h) in a leaching test and could potentially be considered as nutrient-supply media in other applications, thereby recycling the spent zeolites after multiple desalination treatments.

Solvent-Free Synthesis of Zeolites: Mechanism and Utility.

Zeolites have been extensively studied for years in different areas of chemical industry, such as shape selective catalysis, ion-exchange, and gas adsorption and separation. Generally, zeolites are prepared from solvothermal synthesis in the presence of a large amounts of solvents such as water and alcohols in sealed autoclaves under autogenous pressure. Water has been regarded as essential to synthesize zeolites for fast mass transfer of reactants, but it occupies a large space in autoclaves, which greatly reduces the yield of zeolite products. Furthermore, polluted wastes and relatively high pressure due to the presence of water solvent in the synthesis also leads to environmental and safety issues. Recently, inspired by great benefits of solvent-free synthesis, including the environmental concerns, energy consumption, safety, and economic cost, researchers continually challenge the rationale of the solvent and reconsider the age-old question "Do we actually need solvents at all in zeolite synthesis?" In this Account, we briefly summarize our efforts to rationally synthesize zeolites via a solvent-free route. Our research demonstrates that a series of silica, aluminosilicate, and aluminophosphate-based zeolites can be successfully prepared by mixing, grinding, and heating starting solid materials under solvent-free conditions. Combining an organotemplate-free synthesis with a solvent-free approach maximizes the advantages resulting in a more sustainable synthetic route, which avoids using toxic and costly organic templates and the formation of harmful gases by calcination of organic templates at high temperature. Furthermore, new insights into the solvent-free crystallization process of zeolites have been provided by modern techniques such as NMR and UV-Raman spectroscopy, which should be helpful in designing new zeolite structures and developing novel routes for synthesis of zeolites. The role of water and the vital intermediates during the crystallization of zeolites have been proposed and verified. In addition to a significant reduction in liquid wastes and a remarkable increase in zeolite yields, the solvent-free synthesis of zeolites exhibits more unprecedented benefits, including (i) the formation of hierarchical micro-, meso-, and macrostructures, which benefit the mass transfer in the reactions, (ii) rapid synthesis at higher temperatures, which greatly improve the space-time yields of zeolites, and (iii) construction of a novel catalytic system for encapsulation of metal nanoparticles and metal oxide particles within zeolite crystals synergistically combining the advantages of catalytic metal nanoparticles and metal oxide particles (high activity) and zeolites (shape selectivity). We believe that the concept of "solvent-free synthesis of zeolites" would open a door for deep understanding of zeolite crystallization and the design of efficient zeolitic catalysts.

The Effect of an Ultrasound Radiation on the Synthesis of 4A Zeolite from Fly Ash

The use of coal as a fuel source generates a lot of solid waste fly ash. Thus, efforts to reduce or utilize the amount of fly ash are urgently needed. This paper presents zeolite synthesis from fly ash. The fly ash was activated by using NaOH solution prior to fusing process with a weight ratio of 1:2 and mixing with distilled water at a weight ratio of 1:5. Thereafter, the addition of alumina with a concentration of 0.71 %, 1.42 %, 2.12 %, and 2.8 % w/v was performed. The effects of heating and ultrasound radiation on the characteristic of zeolite products were investigated. The results showed that the addition of alumina 2.8 % w/v resulted in the Si/Al ratio of zeolite 4A is ∼1. SEM images demonstrated that the presence of ultrasound wave resulted in crystals structure morphology as also supported by XRD characterization. The average crystal size for the ultrasonic treatment was 42.46 nm.

Directing Aluminum Atoms into Energetically Favorable Tetrahedral Sites in a Zeolite Framework by Using Organic Structure-Directing Agents.

The Al location in zeolites can have massive influences on the zeolite properties because it directly correlates with the cationic active sites. Herein, the synthesis of IFR zeolites with controlled Al distribution at different tetrahedral sites (T sites) is reported. The computational calculations suggest that organic structure-directing agents (OSDAs) used for zeolite synthesis can alter the energetically favorable T sites for Al. Zeolite products synthesized under identical conditions but with different OSDAs are found to have altered fractions of Al at different T sites in accordance with the energies derived from the zeolite-OSDA complexes. Our finding thus provides evidence for the ability of OSDAs to direct Al into more energetically favorable T sites, thereby offering rational synthetic guidelines for the selective placement of Al into specific crystallographic sites.

Directing Aluminum Atoms into Energetically Favorable Tetrahedral Sites in a Zeolite Framework by Using Organic Structure‐Directing Agents

AbstractThe Al location in zeolites can have massive influences on the zeolite properties because it directly correlates with the cationic active sites. Herein, the synthesis of IFR zeolites with controlled Al distribution at different tetrahedral sites (T sites) is reported. The computational calculations suggest that organic structure‐directing agents (OSDAs) used for zeolite synthesis can alter the energetically favorable T sites for Al. Zeolite products synthesized under identical conditions but with different OSDAs are found to have altered fractions of Al at different T sites in accordance with the energies derived from the zeolite–OSDA complexes. Our finding thus provides evidence for the ability of OSDAs to direct Al into more energetically favorable T sites, thereby offering rational synthetic guidelines for the selective placement of Al into specific crystallographic sites.

Hydrothermal synthesis of zeolite production from coal fly ash: A heuristic approach and its optimization for system identification of conversion

Abstract Commercialization of synthetic zeolites has given considerable impetus to optimization of its production routes. The preferred production route involves hydrothermal treatment of coal fly ash in a strong alkali solution. The process involves several parameters, such as reaction temperature, time, the concentration and amount of alkali solution, and silica content in the fly ash, all of which strongly and non-monotonically affect the conversion. We herein perform several experiments with the Kazakhstani fly ash, and obtained a highest conversion of zeolites of 78% using 3 M NaOH at 110 °C. Further, we propose a conversion model using zero-order Takagi-Sugeno fuzzy system to analyze the effect of individual process parameters on conversion, and thereby, the reaction mechanism(s) of zeolite formation. The model is designed and developed, using the data, both from literature and our experiments on Kazakhstani fly ash. The obtained results clearly illustrate that the model accurately predict the conversion percentage of zeolite for a given set of reaction parameters. The model is further optimized to provide accurate inferences and an average deviation between the model predictions and experimental values for zeolite yield is observed to be less than 5%.

Synthesis of 2D MFI zeolites in the form of self-interlocked nanosheet stacks with tuneable structural and chemical properties for catalysis

This study explores a facile synthesis method by simply changing the type of precursor cations or anions to regulate the nanosheet stack size of mesoporous 2D MFI zeolites while preserving the ‘self-interlocked ordered nanosheet stack’ (SI-ONS) microstructural characteristics. The important roles of precursor cations and anions in controlling the structure and hence chemical properties of the 2D MFI zeolites are demonstrated and the corresponding mechanisms are explained. The ability to facilitate microporous MFI framework development followed the order Na+<K+<Rb+<Cs+ for cations and SO42−≈NO3−≈Cl− for anions. Conversely, the capability to generate inter-crystalline mesopores followed the order Na+>K+>Rb+>Cs+ and SO42−>NO3−>Cl−. The cations and anions showed little effect on the number and strength of strong acid sites, but clearly influenced their hydrothermal stability. The hydrothermal stability of strong acid sites in the resulting 2D MFI zeolites followed the order Na+<K+<Rb+ for cations and SO42−<Cl−<NO3− for anions. A general micelle-aggregation mechanism governing the microstructure formation of SI-ONS in precursors containing different types of cations and anions was proposed established. It was found, for the first time, that a linear relationship exists between nanosheet stack size and mesopore volume of 2D MFI zeolites, which provides a valuable indicator for predicting mesopore volume from nanosheet stack size for a 2D MFI zeolite product. Catalytic performance of the synthesized 2D MFI zeolites was examined using three selected liquid phase reactions including the O-methylation of cyclohexanone, the esterification of benzyl alcohol with hexanoic acid and the protection of benzaldehyde with pentaerythritol. It was shown that the catalytic activity of the 2D MFI zeolites was primarily dictated by the amount of mesopores present, for example, the reaction conversion increased by as much as 300% when the mesopore volume increased from 0.05 to 0.55cm3g−1.

Solvent-Free Synthesis of All Silica Beta Zeolite in the Presence of Tetraethylammonium Bromide

We report a solvent-free synthesis of all silica Beta zeolite using a cheap organic template of tetraethylammonium bromide (TEABr). The method includes mixing, grinding and heating solid raw material in the absence of water solvent but the presence of zeolite seeds. The absence of water solvent significantly improves the efficiency of synthesis, while the addition of seeds remarkably enhances the crystallization rate. In addition, the use of a cheap organic template of TEABr greatly decreases the synthesis cost. The effects of the reaction compositions, including the molar ratios of NH4F/SiO2, TEABr/SiO2, and mass ratios of seeds to the silica, on the synthesis of the pure product were investigated using different temperature. Physicochemical characterizations, including XRD, SEM, TG and N2 sorption, show that the zeolitic product has good crystallinity, uniform crystals, and high surface area.

Synthesis of Zeolite A from Mongolian Coal Fly Ash by Hydrothermal Treatment

Raw coal fly ash and acid pretreated fly ash were used to synthesize A-type zeolite by hydrothermal treatment. In order to synthesize zeolite A an aqueous gel having a molar batch composition of Na2O:Al2O3:1.926SiO2:128H2O was utilized. Fly ash and zeolitic products were characterized by SEM, XRF, XRD and cation exchange capacity (CEC). After hydrothermal treatment, several types of zeolites were formed: zeolite A, analcime, faujasite and hydroxy-sodalite. The highest content of zeolite A was formed in the mixture treated at 80°C for 8 hours. CEC values of the zeolitic products were 28-38 times higher than that of in raw fly ash. Acid pretreatment which leads to low calcium and iron content is preferable method for processing of fly ash for the zeolite synthesis. Synthesized zeolite can be used for ion exchangers for water treatment.