Acid Leaching Method Research Articles

Enrichment and extraction of lanthanum from Belitung silica sand using sulfuric acid heap leaching, precipitation and complexation with phytic acid

In this study, enrichment and extraction of lanthanum from Belitung silica sand was carried out using heap leaching, precipitation and complexation methods. Complexation with phytic acid with impurities metal ions on pregnant leach solution (PLS) from silica sand at room temperature was also investigated. This method is cheap, practical, no destruction needed, and the preparation is simple and easy. The precipitation method using sodium sulfate was carried out to separate the metals and impurities present in the solution. The heap leaching of the metals was performed by varying the parameters such as acid concentration (0.001–3 M) and volume of sulfuric acid solution (50–250 mL). Concentration of lanthanide and composition of metal ions of samples were determined using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). The optimum concentration and volume of H2SO4 as a leaching agent was 3 M and 250 mL, respectively, with the result of the lanthanum salt as high as 1.637 ppm. The hexaphosphate groups of phytic acid as active sites is favorable selective to bind with Al3+ metal ions, thus it is expected to have high effectiveness for lanthanum enrichment. From the ICP-OES results in the complexation using phytic acid, lanthanum was obtained of 0.709 ppm (11.29%) with its purity of ∼67%. These results suggested that lanthanum can be extracted from Belitung silica sand using the acid leaching, precipitation and complexation methods.

Preparation of porous alumina adsorbent from kaolin using acid leach method: studies on removal of fluoride toxic ions from an aqueous system

In the present study, feasibility of the porous alpha alumina beads for the removal of fluoride has been investigated. The porous alumina beads were fabricated by choosing the low-cost method i.e., oil drop method through extraction of alumina from kaolin. Extraction of alumina from kaolinite is a well-defined process from long decade. After preparation, alumina beads were characterized using powder X-ray diffractometer (XRD) which shows major phase as alpha alumina (α-Al2O3) with minor phase of theta alumina (θ-Al2O3) at 1050 °C. Further these beads were examined through scanning electron microscopy (SEM) and Brunauer–Emmett–Teller (BET) using N2 adsorption–desorption isotherm. The specific surface area of 54.54 m2/g was estimated through BET experiment. Alumina beads were then used to eliminate the fluoride toxic ions from the aqueous system using adsorption process. Further, the adsorbent dose and kinetics parameters were thoroughly studied to achieve the maximum removal in the aqueous system. The microstructural analysis was carried out before and after the adsorption process using SEM with EDX to compare the surface morphology of the alumina beads. Batch adsorption study show the mechanism and adsorption capacity of the porous alpha alumina beads which suggests the Freundlich adsorption i.e., heterogeneous behavior of fluoride ions towards alumina surface. Through batch adsorption study it was clearly observed that adsorption belongs to pseudo second order kinetic with inter particle diffusion. At initial fluoride concentration of 10 mg/L (adsorbent dose = 3 g/L; pH 6.7 ± 0.3; time = 48 h) the defluoridation efficiency was 26% with Freundlich adsorption capacity kf = 0.91795 (mg/g) (L/mg)1/n.

Carbon-silica mesoporous composite in situ prepared from coal gasification fine slag by acid leaching method and its application in nitrate removing

Coal gasification fine slag (CGFS) was produced in the coal gasification process which was classified as an industrial solid waste. It was featured with naturally formed amorphous structures and an abundance of silicon, carbon and metal oxides. In this study, on the basis of the composition and structure characteristics of CGFS, a simple hydrochloric acid (HCl) leaching technology was applied to in situ prepare carbon-silica mesoporous composites (CSMCs) from CGFS by fully considering the value of the residual carbon. Special focus was put on the novel mechanism of pore formation in amorphous silica glass microspheres (SGM) during acid leaching. Experimental evidences showed that the metal oxides were uniformly distributed in SGM thus the dissolution of the metal oxides were starting from the surface of SGM, then gradually extending to the interior, and finally leading to form “tree branch” mesoporous channels. In addition, a response surface method was used to predict the optimal reaction conditions and the optimal sample (named as CGFS-O) was successfully prepared. CGFS-O possessed a prominent specific surface area (SSA) (337.51 m2/g) as well as an excellent pore volume (0.341 cm3/g). CGFS-O also exhibited a desirable capacity for NO3− removing and the adsorption process was studied detailed by changing different adsorption conditions. Adsorption results proved that CSMCs have the potential to purify wastewater in an economically and environmentally way. Therefore, combined with a proof-of-concept adsorption performance experiment, our study has not only provided a cost-effective strategy to industrially prepare CSMCs, reutilizing CGFS in an environmentally friendly way, but also contributed to the future applications of CSMCs with valuable insights into the pore formation mechanism in SGM during acid leaching process.

Synthesis, characterization, and performance of graphene oxide and phosphorylated graphene oxide as additive in water-based drilling fluids

Graphene oxide (GO) and phosphorylated graphene oxide (PGO) have been synthesized from graphite electrode waste (GrW) or spent pot lining (SPL) from industrial aluminum wastes. The graphite waste was successfully recovered from the industrial aluminum wastes by alkaline and acid leaching method. The GO was then synthesized according to modified Hummers method in room temperature. The addition of oxygen into graphite structure was indicated by the formation of new vibrational bands at 3344, 1727, and 1069 cm−1 in the infrared (IR) spectrum, and the increase of oxygen content was confirmed by energy dispersive X-ray (EDX). The formation of single or few layers of graphene is confirmed through X-ray diffraction (XRD) analysis which show a down shift of 2θ peak and longer interlayer distance. Additional phosphate group to graphene oxide in functionalization process, in order to enhance the dispersion of graphene in water, was confirmed by scanning electron microscopy-energy dispersive X-ray (SEM-EDX). The effect of heat treatment on phosphorylated graphene oxide (PGO) was investigated by calcination at different temperatures (200–500 °C). The Fourier transform infrared (FTIR) spectroscopy and EDX results indicated that heat treatment decreased the oxygen containing group in PGO. An addition of GO as additive in water-based drilling fluids resulted in better rheology properties (plastic viscosity (PV) reduced from 10 to 7 cp and yield point (YP) increased from 11 to 15 lbs/100 ft2), an increase in fluid loss control performance (filtrate volume decreased from 6 mL to 3.6 mL and filter cake thickness reduced from 1.06 to 0.33 mm), and an increase in lubricity ability (lubricity coefficient reduced from 0.158 to 0.119). In the alkaline environment, the bentonite particles are negatively charged, and GO may also turn to be negatively charged. The repulsive static interaction might reduce the plasticity. The zeta potential of the GO and PGO was measured to be −38.90 and −41.23 mV, indicating that both are not easily agglomerated. The additional PGO as additive in water-based drilling fluids showed a negative impact due to significant pH decreased of drilling fluid.

Reduction-ammoniacal leaching to recycle lithium, cobalt, and nickel from spent lithium-ion batteries with a hydrothermal method: Effect of reductants and ammonium salts

Some inevitable issues of the acid leaching method used to recycle spent lithium-ion batteries (LIBs), such as toxic gas emission, excessive acid-base consumption, inferior metal selectivity and equipment corrosion, have gradually emerged and restricted the promotion and development of this method. It is therefore essential to develop a sustainable closed-loop recycling technology (reduction-ammoniacal method) for spent LIBs. In this study, the effects of various species of ammonia, ammonium salts and reductants on the leaching of Li, Co, Ni, Mn and Al from spent LIBs were investigated with a hydrothermal method. An increase of the electrode potential of the reductant greatly accelerated the selective leaching of Li, Co and Ni, which agreed with the thermodynamic analysis results. The standard electrode potentials of the LiNixCoyMn1−x−yO2 (NCM) materials were also determined by using approximate calculations. When using (NH4)2SO3 as a reductant in a one-step leaching process, 100% Co, 98.3% Ni and 90.3% Li were extracted into the ammonia-ammonium chloride solutions. From the kinetics analysis, the surface chemical reaction shrinking core model was found to control the leaching behavior of Li, Co, and Ni in the reduction-ammoniacal leaching process. A shell-core structure was composed of a product layer, a diffusion layer of the solid core and an unreacted core. Species in the product layer reduced the leaching efficiencies of Li, Co, and Ni. The results obtained for this hydrothermal reduction-ammoniacal method applied to recycle spent LIBs provide insights for the design of a high-speed, exceptionally selective, closed-loop recycling technique.

Effect of oxalic acid-leaching levels on structure, color and physico-chemical features of palygorskite

Palygorskite (Pal) was treated with organic acids to explore effects of acid-leaching levels on its structure, shape of rod crystals, color and physico-chemical features. The leaching behavior of octahedral cations of Pal was studied by evaluating the effect of organic acid types, concentration and reaction time. The results show that oxalic acid (OA) has the strongest ability to leach octahedral metal cations in selected organic acids. OA, having acidity, complexing ability and reduction ability, can be attached to the surface of Pal to promote the leaching reaction, and the position at which the reaction occurs is concentrated on the cylinder surface of the rod crystal. The occupied position of metal cations in the octahedral sheets is the key factor in controlling the leaching of Pal. Mg2+ ions at the edge of the octahedral sheet prefer to leach out, then gradually deepens into the interior octahedral sheet, and Fe3+ and Al3+ ions are leached in turn. When the metal cations are almost completely leached, it means that the octahedral sheets are almost eliminated, at this time, the stacked structure is maintained by the deformed tetrahedron. Compared to conventional inorganic acid leaching methods, organic acid leaching does not destroy the shape of the Pal nanorods. Finally, the one-dimensional amorphous silica nanorods with high SiO2 content of 91.68 wt%, decent rod length, large specific surface area (323 m2/g), high porosity and high whiteness (L* = 86.6, a* = 0.1, b* = 3.2) were obtained by leaching with 1 M OA solution for 120 h, indicating that the non-destructive dissolution of the Pal was achieved.

Utilization of leached MnO2 for the mechanosynthesis of nano LaxCa1-xMnO3 and LaxSr1-xMnO3: Sinterability and properties

The present study focuses on the leaching of MnO2 form manganese ore by acid leaching method using glucose as a reducing agent. The leached MnO2 was used to prepare nano LaxCa1-xMnO3 and LaxSr1-xMnO3 (x = 0.1, 0.3, 0.5 and 1) perovskites by mechanical activation method in the presence of La2O3, CaO or SrO. The leached MnO2 and synthesized perovskite powders were investigated by x-ray diffraction technique (XRD) and transmission electron microscope (TEM).The prepared LaxCa1-xMnO3 and LaxSr1-xMnO3 perovskites were subjected for sintering up to 1350 and 1400 °C, respectively. The physical, electrical and magnetic properties as well as microstructure of sintered perovskites were investigated. The results showed that MnO2 was successfully leached and utilized for preparation of nano LaxCa1-xMnO3 and LaxSr1-xMnO3 perovskites after milling for 8 h. LaxCa(1-x)MnO3 was sintered at 1350 °C while LaxSr(1-x)MnO3 was sintered 1400 °C. The doping with Ca and Sr led to decreasing the electrical resistivity, while they led improving the magnetic property until specific limit (x = 0.5) after which magnetic property was decreased again with increasing their amounts. The highest magnetization was obtained for La0.5Ca0.5MnO3 and La0.5Sr0.5MnO3. In all cases, their values were higher than that of pure LaMnO3.

Selective extraction of uranium from uranium–beryllium ore by acid leaching

Both uranium and beryllium are very important strategic metals and have been applied to many fields, such as nuclear industries, atomic energy, metallurgical industries and telecommunications industries. When uranium and beryllium in the ore were leached simultaneously, a complicated downstream separation process was needed. Based on the different chemical stabilities of uranium and beryllium, an acid leaching method was employed in this work to selectively extract uranium from uranium–beryllium ore. The effects of sulfuric acid concentration, temperature, liquid–solid ratio and leaching time on the leaching efficiency were studied experimentally. Results indicated that treatment of the ores in 0.2 M sulfuric acid at 348.5 K for 50 min with the solid–liquid ratio of 0.25 g/mL is optimum. Under optimal conditions, the leaching efficiencies of uranium is 97.4% and the leaching efficiencies of beryllium is 1.78%, and the standard deviation of them are less than 2% and 0.06%, respectively. Results of kinetic study suggest that the leaching process of uranium was thermodynamically favorable and was controlled by the diffusion of the product layer, whereas the rate-determining step for beryllium leaching is the surface chemical reaction.

Recovery of iron from electric arc furnace slag: effect of heating temperature and time

This work presents the iron oxide recovery from electric arc furnace slag with different temperature and time using acid leaching method. The results showed that formation of iron oxide from electric arc furnace (IO-EAFS) was influenced by the temperature and time of heating. This is evidenced by constant acid concentration and liquid to solid ratio, 5 hours of heating time was exhibited the highest amount of iron ion in extracted solution. The maximum of iron extract in heating temperature was at 100 °C. Throughout the characterization using Scanning Electron Microscopy (SEM), the iron oxide illustrated the microstructures were agglomerates predominantly with irregular shapes and XRD results further colobrated the presence of hematite combined with other metal oxide exists in the IO-EAFS. From the TGA analysis, it was identified that the recovered iron oxide was totally decomposed at 525°C. This results indicate that electric arc furnace slag is potential material of iron oxide for the future appliction.

Hierarchical ZSM-5 based on fly ash for the low-temperature purification of odorous volatile organic compound in cooking fumes

Hierarchical ZSM-5 (HZ) zeolites with different SiO2/Al2O3 ratios (SiO2/Al2O3 = 50, 100, 150, 200, 250 and 300) were synthesized using a two-step hydrothermal treatment method, and the Al and Si were obtained from fly ash by the alkali melting and acid leaching method. On this basis, the 10 wt% LaMnO3/HZ catalysts were prepared by impregnation. The all the synthesized catalysts were investigated for the low-temperature (200 °C) catalytic oxidation of pentanal, which was selected as a typical odorous volatile organic compound (VOC) in cooking fumes. In addition, the physicochemical properties of HZ zeolites were characterized by several techniques (XRD, N2 physical adsorption–desorption, ICP-OES, SEM,TEM,NH3-TPD and 27Al MAS-NMR). The results showed that the HZ zeolite, which was micro-mesoporous material and had high specific surface area, provided a higher diffuser efficiency for long-chain VOC gas. The catalytic performance of HZ zeolite was better than that of the traditional ZSM-5 zeolite. Compared with the dry atmosphere, HZ-100 zeolite, which possessed more proper medium strong acid sites and the appropriate amount of acid sites, had the higher pentanal catalytic combustion conversion of above 92% and the relatively superior stability with 2 V% water steam in air, indicating that the suitable acid sites can form the best synergistic catalytic effect with water molecules for purifying long-chainVOC gas. In addition, the catalytic conversion of pentanal on 10 wt% LaMnO3/HZ-100 was 100% with no deactivation, and compared with HZ under a dry atmosphere, the average CO2 yields of 10 wt% LaMnO3/HZ catalysts in the steady catalytic oxidation stage under a dry atmosphere and 2 V% water steam in air were improved by 6–18% and 13–20%.

Novel Approach for Synthesis of Mesoporous γ-AlOOH Powder from Coal-Bearing Kaolinite and its Enhanced Adsorption Performance for Congo Red and Fluoride

Mesoporous boehmite (γ-AlOOH) was synthesized from naturally occurring coal-bearing kaolinite (CBK) by direct sulfuric acid leaching and hydrothermal method to explore a new possible route to the synthesis of product with high value added using the CBK. The Brunauner-Emmett-Teller (BET) surface area and the average crystallite size of the γ-AlOOH powder could be controlled in the range from 6.3 to 192.5 m2 g-1 and from 5.5 to 14.4 nm, respectively, by varying the reaction temperature and reaction time. Owing to its porous structure and high surface area, the synthesized mesoporous γ-AlOOH powder exhibited better adsorption abilities for CR and fluoride in contrast to commercial boehmite, and it only took 20 min to reach removal efficiency of 99.6% for CR and 90.5% for fluoride, when the initial concentration of CR and fluoride was 100 and 10 mg L-1, respectively.

Understanding the role of water-based electrolytes on magnesium-ion insertion/extraction into λ-MnO2 lattice structure

In rechargeable batteries, the different anionic groups of the electrolyte salt having same cation play an importance role in improving electrode material performance due to their intrinsic characteristics which affect ion migration process, structural stability and self-discharge. To this end, we investigate Mg2+ ion insertion into λ-MnO2 structure with aqueous electrolytes that contain three different salts of Mg. Experimental study includes both material characterizations performed to describe the physical properties of the active material and battery performance tests of the working electrode in Mg-based aqueous mediums. Herein, λ-MnO2 that functions as an inorganic electroactive template is synthesized by extracting Li+ ion from LiMn2O4 through acid leaching method. Electrochemical performance of the spinel-type positive electrode material is evaluated by means of cyclic voltammetry (CV) and galvanostatic charge-discharge measurements. In charge-discharge tests conducted at C/10 current density, λ-MnO2 electrode deliver approximately a reversible discharge capacity of 70 mAh g−1 in 1 M MgSO4, 20 mAh g−1 in both 1 M MgCI2 and 1 M Mg(NO3)2 after 100 cycles. C-rate performance tests are carried out for the samples in which the electrolyte contained MgSO4 salt, and the result is found to be around 220 mAh g−1 capacity at C/40 current rate. Concurrently, the insertion of Mg2+ ion is confirmed by EDX-mapping and XPS analysis after the first reduction step.

Case study on removal of heavy metals from waste incineration fly ash by acid leaching method

Case study on removal of heavy metals from waste incineration fly ash by acid leaching method

Appropriate titanium slag composition during smelting of vanadium titanomagnetite metallized pellets

The suitable titanium slag composition with high titanium content for electric furnace smelting of vanadium titanomagnetite was investigated through thermodynamics and related phase diagram analysis. According to the thermodynamic results, low-melting-point regions and MgTi2O5 primary phase area in the phase diagrams, the suggested titanium slag composition for the present vanadium titanomagnetite metallized pellets should consist of 50% TiO2, 8%–12% MgO and 13% Al2O3 (mass fraction) with a binary basicity of 0.8–1.2. Finally, the verified smelting experiments were conducted and successful separation of the molten iron from the titanium slag is obtained. The obtained vanadium-containing molten iron contains 0.681% V and 0.267% Ti, and the obtained titanium slag contains 52.21% TiO2 (mass fraction), in which MgTi2O5 is the primary phase. The titanium resource in the final titanium slag production could be used to produce TiO2 pigment by acid leaching methods.

Acid Leaching Extraction of Mo, V, and Ni Compounds from the Semicoking Product of Tar Hydroconversion Residue

The results of studies of the extraction of Mo, V, and Ni compounds contained in the semicoking product of tar hydroconversion residue by an acid leaching method are presented. The aqueous solutions of HNO3, H2SO4, and H2O2 were used as reagents for the leaching. Conditions for the extraction of 80–90% metals from the semicoke were determined. The possibility of decreasing the sulfur content of the semicoke by a factor of more than 2 was demonstrated. According to the calculated kinetic characteristics, the reaction of molybdenum leaching by the test reagents corresponds to a higher degree to a first-order kinetic equation (R2 > 98%).

Thermomagnetic concentration and dephosphorizing of brown clay iron ore and concentrates

Oolitic brown clay iron ores are of prime economic importance because of their enormous stocks in the world. However, their use in metallurgical production is very severely limited at the present time because of the high content of phosphorus in them. The process of phosphorus extracting from these ores almost cannot be realized by the known enrichment methods, since phosphorus presents in oolites in the emulsionated and impregnated state, without forming the independent minerals in this case. Therefore, using of ores of the given type is very limited. Growth of the world steel production at this time has considerably increased demand for iron ore, for that reason in the last decades in the world there were made considerable efforts on creation of new manufacturing schemes of brown clay iron ores obtaining standard iron ore concentrates. Considerable reduction of rich and easily beneficiated iron ores in Kazakhstan results in necessity to attract in metallurgical production the huge resources of the easily extracted ooli tic brown clay iron ores of Lissakovsk, Ayat, Priaral, and other fields with the iron content from 35 to 40 % and phosphorus up to 1 %. The technology of thermomagnetic beneficiation is represented as the most self-sustainable and acceptable dephosphorizing technology of brown limonites. The essence of the technology consists in the reproduction by liquid hydrocarbon reducer (LHR), mesmerizing roasting of the concentrate, magnetic concentration of the roasted raw material receiving the magnetic concentrate with the subsequent dephosphorizing of the obtained concentrate by the acid leaching method. The technology was tested in pilot conditions by representative samplings of the Lissakovsk concentrate and the ores of Ayat and Kokbulak fields.

Comparative Study of Water-Leaching and Acid-Leaching Pretreatment on the Thermal Stability and Reactivity of Biomass Silica for Viability as a Pozzolanic Additive in Cement.

The present work aims to introduce a novel and eco-friendly method, i.e., a water-leaching pretreatment for extracting highly reactive biomass silica from rice husk (RH), for viability as a pozzolanic additive in cement. For comparison, the traditional acid pretreatment method was also employed throughout the experimental study. The silica from RH was extracted using boiled deionized water and acid solution as leaching agents to remove the alkali metal impurities, and then dried and submitted to pyrolysis treatment. The results indicated that potassium was found to be the major contaminant metal inducing the formation of undesirable black carbon particles and the decrease in crystallization temperature of amorphous RHA silica. The boiling-water-leaching pretreatment and acid-leaching pretreatment on RHs significantly removed the metallic impurities and reduced the crystallization sensitivity of RHA silica to calcination temperature. A highly reactive amorphous silica with purity of 96% was obtained from RH via 1 N hydrochloric acid leaching followed by controlled calcination at 600 °C for 2 h. The acid treatments increased the crystallization temperature of silica to 1200 °C and retained the amorphous state of silica for 2.5 h. In the case of water-leaching pretreatment, leaching duration for 2.5 h could yield an amorphous silica with purity of 94% and render the silica amorphous at 900 °C for 7 h. The RHA silica yielded by water-leaching pretreatment presented a comparable enhancing effect to that of acid leaching on hydration and improved the strength of cement. Furthermore, compared with the acid-leaching method, the water-leaching pretreatment method is more environmentally friendly and easier to operate, and hence more widely available.

Co-utilization of spent pot-lining and coal gangue by hydrothermal acid-leaching method to prepare silicon carbide powder

Spent pot-lining from aluminum electrolysis and coal gangue are toxic and hazardous solid wastes with high recovery value and contents of valuable elements, such as carbon, silicon, aluminum and fluorine. Thus, harmless treatment and recycling of these materials are of considerable importance. For extracting valuable components, Spent pot-lining and coal gangue were co-treated by hydrothermal acid-leaching method in this study. Effect of adding spent pot-lining on impurities leaching rate of coal gangue was systematically studied, and results indicated that fluoride in spent pot-lining positively affected the decomposition of coal gangue. Moreover, effects of leaching temperature, initial acid concentration, time, and particle size, on the extraction efficiency of aluminum were investigated comprehensively. Optimum parameters obtained by single-factor test included reaction temperature of 200 °C, initial hydrochloric acid concentration of 10 mol/L, time of 10 h, liquid–solid ratio of 10:1, and particle size below 200 mesh. Under these conditions, leaching rate of aluminum reached to 92.47%. Acid-leaching residue was used in the preparation of silicon carbide powder by carbothermal reduction, and silicon carbide powder with small size (D50, the median diameter, of 18.15 μm) was obtained by firing the acid-leaching residue at temperature of 1600 °C for 5 h. This study provides an inspiring approach for recovering and reusing spent pot-lining and coal gangue.

Recovery of Lanthanides from Indonesian Low Grade Bauxite Using Oxalic Acid

The present work describes the extraction of lanthanide (rare earth elements, REE) from low grade bauxite using acid leaching method. The aim of this study is to obtain the best condition for extraction of lanthanides from low grade bauxite. The effect of different parameters such as temperatures and concentration of oxalic acid in leaching process were investigated. The content of La, Ce and Y elements were determined using ICP-OES. The experimental result shows that the efficiencies of lanthanide leaching are the temperature-dependent. Increasing leaching temperature from 45°C to 85°C did not improve recoveries of lanthanides. The most optimum condition was found at oxalic acid leaching of 1 mol/L, leaching temperature at 40°C, and time for 2 hours. The obtained results show that the lanthanides can be leached using oxalic axid. This finding may lead to more effective and economical method to separate lanthanides from low grade bauxite.

Accelerated crystallization of magnetic 4A-zeolite synthesized from red mud for application in removal of mixed heavy metal ions

To cope with the increasing environmental issues of red mud, an integrated technological route for its comprehensive utilization was developed through the extraction of valuable components and the synthesis of magnetic 4A-zeolite. To accelerate the crystallization process of the synthesized 4A-zeolite, sodium chloride (NaCl) was innovatively employed under hydrothermal treatment. The effects of various parameters, including mass ratio of red mud/NaOH, alkali fusion temperature, alkali fusion time and molar ratio of NaCl/Al2O3, were systematically investigated. The results showed that approximately 81.0% Al, 76.1% Si and 95.8% Fe were utilized from red mud using alkali fusion and acid leaching methods. The optimal conditions of the alkali fusion process were determined as: mass ratio of red mud/NaOH = 1/2, alkali fusion temperature of 800 °C, and time of 90 min. Furthermore, when the molar ratio of NaCl/Al2O3 was kept at 1.5, the crystallization time reduced from 240 min to 150 min, and particle size distributions narrowed from 20–100 μm to 1–10 μm. The practical applications in removal of mixed heavy metal ions (Zn2+, Cu2+, Cd2+, Ni2+, and Pb2+) from wastewater indicated that the as-synthesized magnetic 4A-zeolite is a promising candidate for heavy metals adsorption.