Remove Iron Ions Research Articles

Efficacious sensing and elimination of iron ions from aqueous medium by polyethylenimine functionalized carbon dot

In the present work, Iron (Fe) ions are detected and removed from an aqueous medium using a green emissive polyethylenimine functionalized carbon dots (GPC), which are produced hydrothermally and have high adsorption efficiency and sensitivity. As prepared, GPC uses an adsorption approach to remove iron ions and a Turn-Off mechanism to detect iron ions. A UV-Vis and photoluminescence spectroscopy are used to evaluate the results of several experiments, including those involving the interference of other ions, changing the concentration of metal ions, pH, reaction time, and the dosage of adsorbent in the sensor, in an attempt to achieve high sensitivity (with a lower limit of detection of 0.08 ppm) and high adsorption efficiency of approximately 98 % (8 µM of Fe and 1 ppm of GPC) towards iron ions. The isotherm and kinetic analyses of adsorption show that pseudo-second-order kinetics and Freundlich isotherm suits the experimental data better. With a removal percentage of roughly 89 percent after three cycles, desorption analysis highlights its regeneration efficiency. The mechanism of adsorption and quenching are extensively investigated; The static and dynamic quenching mechanisms are supported by high static constant value of approximately 23.5 ×103 M and the lifetime decay declination of 2.42 ns, respectively. Zeta potential measurements and XPS analysis are used to examine the electrostatic interaction between GPC and Fe in the adsorption mechanism. Ultimately, the prepared material's contentment results illustrate its potential for practical applicability with five actual water samples.

Environmentally safe technology of waste processing of galvanic production

It is known that waste is difficult to purify using existing reagent methods to the standards of the MPC. In addition, the formed sediments contain poorly soluble hydroxy compounds of heavy metals and gypsum, which makes it impossible to dispose of iron- and copper-containing electroplating sludges. The purpose of the study was to study the possibility of ion exchange separate and simultaneous extraction of iron and copper ions from acidic solutions of pickling and copper plating in galvanic production to obtain ferrites. In the course of research, the highly acidic cation exchange resin Dowex HCR S/S in the H+ form was chosen as the cationite. The choice of a strongly acidic cationite is justified, based on the fact that cationites of this type are able to easily lose hydrogen ions due to their displacement from the cationite matrix by other cations of the solution. The sorption processes of iron (II) and copper (II) ions were carried out under dynamic conditions. In the course of experimental studies, it was shown that with an increase in the concentration of sulfuric acid, the full exchangeable dynamic capacity of the cationite significantly decreases both during the sorption of iron ions and during the sorption of copper ions. For iron-containing solutions, full dynamic exchange capacity decreases from 1.39 g-eq/dm3 in the absence of H2SO4 in the initial solution and decreases to 0.3-0.46 g-eq/dm3 at a concentration of sulfuric acid at the level of 1-3 g/dm3. An increase in the concentration of iron (II) ions leads to a significant increase in full dynamic exchange capacity, even with a concentration of sulfuric acid of 8 - 13 g/dm3, full dynamic exchange capacity was at the level of 1.35 g-eq/dm3, which corresponds to the level of sorption of diluted solutions even in the absence of acid. However, the total concentration shows that the efficiency of sorption of metals from acidic solutions remains quite high and increases with the increase of the initial total content of sorbed ions. The main indicator used when choosing an ion exchange method is the possibility of effective regeneration of the cation exchange material. When using 5% solution of sulfuric acid already at the specific consumption of the regeneration solution, it was possible to achieve a degree of regeneration at the level of 95-98%, and when using 10% solution, the degree of regeneration reached 100%. According to the developed technological scheme, regeneration solutions are processed by precipitation into magnetite in a ferritizer reactor. To remove iron ions from concentrated iron-containing regeneration solutions by the ferrite method in order to obtain ferrite particles (magnetite) with maximum magnetic properties, a mixture of Fe (II) and Fe (III) sulfates was used with their concentration ratio K = [Fe2+]/[Fe3+] = 0.5, as a stable relationship between magnetic properties and sediment volume was noted. At maximum magnetic properties, the sediment volume is minimal, and vice versa. Obtaining highly dispersed magnetic particles from a mixture of ferric and ferric sulfates by precipitating them with 10% NaOH solution during heating allows to significantly reduce the duration of the process, simplify it and increase the productivity of the equipment. To obtain magnetic particles of copper ferrites from regeneration solutions by precipitation with alkali at normal temperatures, the concentration ratio K1 = [Fe2+]/[Cu2+] = 3.15-7.76 should be maintained. With an increase in the concentration of Cu2+ ions, there is an increase in the period of crystallization of the obtained sediments and their acquisition of magnetic properties. The formed ferrite material can be used for environmental purposes as a valuable raw material for carbon monoxide neutralization catalysts, as part of alkaline cement for concrete products, or sent for safe disposal. The obtained results on the application of ion-exchange extraction of iron and copper ions from acidic solutions of galvanic production are expedient as the first stage of complex ecologically safe processing of galvanic wastes with the production of ferritic materials for industrial use.

Self-hydrolyzing Submerged Flow Technology for Acid Coal Mine Drainage Treatment: Effective Removal of Iron Ions

In this study, mine wastewater from Leiyang, Hunan Province was taken as the research object to investigate the effect of using the method of self-hydrolytic submerged sedimentation to treat acid coal mine drainage. It was found in this study that the removal rate of sulfate ions and iron ions from the acidic coal mine drainage stock solution at pH=2.7 was very limited by self-hydrolytic sedimentation experiments relying only on pure vertical sedimentation flow treatment, but the hydrolytic treatment could greatly improve the solution environment and promote the formation of secondary minerals of sulfate ions and iron ions in the acidic coal mine drainage, which greatly improved the removal rate of iron ions. Both suspended and precipitated materials produced in the self-hydrolysis sedimentation experiments were hydroxylated iron sulfate secondary minerals- Schwertmannite [Fe8O8(OH)8-2X(SO4)X (1 ≤ x ≤ 175)], the formation of which is inextricably linked to the low pH environment and high concentration of sulfate and iron ions in coal mine wastewater. Self-hydrophoretic submerged flow can remove iron ions from acidic coal mine drainage at low cost and high efficiency, and the total iron removal rate of this system can reach 90.93% after 24 h of treatment, which has a favorable comprehensive utilization value.

Chitosan/Alginate nanocomposites containing magnetic nanoparticles and multi-wall carbon nanotubes for efficient iron sorption

The widespread presence of iron pollution in groundwater is a major global worry, as increased levels can lead to severe health hazards. To tackle this urgent problem, we engaged in a synthesis procedure where magnetic nanoparticles (MNPs) and multi-wall carbon nanotubes (CNTs) were combined with a mixture of chitosan (CS) and sodium alginate (Alg) to produce a magnetic composite material. This novel composite, known as CS/Alg/MNPs/CNTs, was crafted with the primary aim of effectively removing iron from groundwater through adsorption. A thorough physicochemical analysis using FTIR, SEM, PSA, XRD, DSC, and TGA confirmed the composition's characteristics. The study delved into the influence of parameters such as retention time, sorbent dose, initial Fe concentration, pH, agitation rate, and temperature on the adsorption process. The Langmuir isotherm model fittingly represented the adsorption data, indicating a monolayer coverage of 12.43 mg/g and aligning with the pseudo-second-order kinetic model. Additionally, the adsorption of iron ions by the composite material was identified as a endothermic process. Furthermore, the study highlights the sorption process's inherent spontaneity and survivability, as demonstrated by the negative ΔG value. In conclusion, the results of this study indicate that the magnetic composite adsorbent (CS/Alg/MNPs/CNTs) holds considerable promise for effectively removing iron ions from groundwater, making it a viable and attractive choice for use in water purification applications.

Role of solution acidity on ferrous ions mineralization process at low temperature of 393.15 K, 408.15 K, and 423.15 K

Here, a clean, low-temperature hematite process using a neutralizer was proposed to remove iron ions from a zinc leaching solution and reutilize iron removal residue. The results showed that the solution acidity played a crucial role in this process. For a ZnSO4 solution with an Fe2+ concentration of 12–14 g/L and an initial pH > 3.0, the iron ion concentration decreased to 20 mg/L within 95 min when using the low-temperature hematite process with pure ZnO (10–13 g/L) added as a neutralizer in the temperature range of 408.15–423.15 K. The iron removal efficiency reached 99%. Increasing the initial pH of the initial solution significantly improved the iron removal efficiency, and it was necessary to control the pH above 3.0. After ferrous ion mineralization, the residual iron concentration in the solution was inversely proportional to the final pH. The precipitated hematite products contained an Fe content of >55%, with a Zn loss of <1% and S contamination level of <3%. These hematite products can be sold as raw materials for ironmaking to solve the environmental issues associated with the storage of iron removal residue. The results showed that zinc oxide dust could not be used as a neutralizer because it resulted in the loss of valuable metals such as Pb, Ag, and In. Compared with the hematite process (453.15–473.15 K, reaction time of 3.0 h) used by the Iijima Refinery of Akita Zinc Co. in Japan, the ferrous ion mineralization in this study was shortened to <100 min. This significantly increased the treatment capacity of the low-temperature hematite process for zinc leaching solutions. The low-temperature hematite process could be performed at 393.15 K, 408.15 K, and 423.15 K, which can realize energy savings and consumption reduction.

SEPARATION OF IRON IONS FROM SOLUTIONS OF HYDROMETALLURGICAL INDUSTRIES BY LIQUID EXTRACTION METHOD

In the article, the author considers the problem of choosing a method of extracting valuable components from the production solutions of hydrometallurgical production. For this purpose, it is promising to use the liquid extraction method. With the help of this method, in the field of metallurgy, during the production of non-ferrous metals, technological solutions can be used to remove iron ions. Depletion of mineral reserves requires the use of only poor natural materials for industrial enterprises. One of the promising methods of separating metal ions from poor solutions by freeing them from co-existing elements and obtaining a concentrated solution is extraction. In addition, the extraction method is only effective in processing high-iron solutions, because it allows to significantly reduce the amount of iron that goes to the heap. The use of liquid extraction method in the purification of solutions from iron ions significantly facilitates the separation of iron ions from non-ferrous metal ions. The conducted study showed that, when the concentration of the organic phase is correctly determined, it is possible to use toluene as a solvent and trialkylamine (TAA) as a reagent for the separation of iron ions from technological solutions containing acid. The obtained data showed that the use of toluene as a solvent and trialkylamine (TAA) as a reagent during extraction is promising. Keywords: liquid extraction, extractant, raffinate, iron ions, toluene, trialkylamine.

Photo-Fenton process applied for the treatment of industrial wastewaters containing diclofenac: optimization with low iron ions concentrations and without pH control

Diclofenac (DCF) can cause several adverse effects in the environment and it should be removed from industrial pharmaceutical wastewaters. Advanced oxidation processes (AOPs) are promising methods for the DCF degradation. But, in many cases, AOPs require acidic pH. However, at this condition, DCF precipitates, which may hinder its oxidation. Thus, in this work, some AOP were studied for the DCF degradation, especially the photo-Fenton process, applying the experimental design technique (Doehlert matrix), operating without and with pH control (between 6.5 and 7.0). As independent variables, the initial ferrous ion concentration ([Fe2+]) and the molar addition rate of H2O2 (FH2O2) were evaluated. Empirical models were proposed and optimized conditions were determined without ([Fe2+] = 0.27 mmol L−1 and FH2O2 = 1.64 mmol min−1) and with pH control ([Fe2+] = 1.0 mmol L−1 and FH2O2 = 1.64 mmol L−1), with the following predicted mineralization percentages: 93% and 68%, respectively. So, photo-Fenton process without pH control presented the best performances. Furthermore, at this condition, iron concentration respects the limit value established by the Brazilian environmental legislation. That is, in this condition, additional processes, in order to remove iron ions, would not be necessary, that is very interesting for applications on an industrial scale.

Chemical adsorption of iron ions from drinking water using Jordanian zeolitic tuff

Jordanian natural zeolitic tuff is distributed in the northeast, central and southern parts of Jordan. Zeolitic tuff used in this work was brought from Al Hala Volcano piles located in the southern part of Jordan to investigate its capability to remove iron ions from drinking water. The main zeolitic minerals identified in Al Hala are phillipsite and chabazite. The effects of iron concentration, pH values, contact time, zeolite grain size and amounts of used zeolitic tuff were examined in the removal process using batch experiments. Two zeolitic tuff grain sizes with two different amounts were used and designated as HZ1 and HZ2, two iron concentrations from two different water wells were investigated and designated as W1 and W2 were examined for different contact time periods. Batch tests were performed to determine the ability of zeolite to remove Fe3+ (iron III) from drinking water. In static regime experiments, the use of the HZ2 type shows a higher percentage of Fe3+ removal as compared to the HZ1 type for the same time and concentration. The results indicate that iron ions can be removed from drinking water with approximately 100% efficiency at the beginning of the contact time regardless the concentration of iron ions in the water. Al Hala zeolitic tuff used in iron removal showed a high capability with complete Fe3+ removal from drinking water. The HZ2 is more efficient in iron ions removal than HZ1, the pH value is not significantly affected.

A Novel Method for Removal of Iron Ion Contamination in Patchouli Essential Oil

Nowadays, in the aromatic and cosmetics industries, as well as an additive for food flavoring, patchouli essential oil (PEO) is a significantly crucial raw material. This oil is extracted from Pogostemon cablin, a plant from the Lamiaceae family. The standard method to obtain this oil is steam distillation. However, applying this method, the oil has a relatively high iron content. A contaminated iron ion can arise in the PEO for some reasons, i.e., the distillation practice used in a non-stainless steel tank, the PEO stored in an iron drum, or even the water for steam production was not appropriately treated. Activated carbon adsorbents can be used to remove contaminants from liquids or gasses by adsorbing ions, complexes, and molecules from aqueous solutions. Although fine adsorbent particles offer advantages in terms of adsorption capacity and kinetics, the application of the adsorbent to remove iron ions contaminated in PEO is not simple work. It is because a problem with these particles is widely dispersed in the oil and challenging to recover and contaminates the final product of PEO. This study developed a novel method to remove iron ions contaminated in a PEO using a modified activated carbon, i.e., magnetic activated carbon (MAC). For practical applications, using MAC material will reduce operating costs and solve the problems related to the quality of the end product, i.e., contamination by the adsorbent. The result shows that the MAC material improved the quality of PEO by reducing iron ion concentration in the oil from the initial concentration of 194 mg/L to around 87 mg/L. As expected, the adsorbent allows rapid removal from the PEO by using a magnetic source. Based on this study, MAC material enables the reduction of iron ion contamination in PEO and produces a free-adsorbent in the final product.

Removal of artificial iron ions using activated carbon from sago pith waste

In the present day, the industry is growing rapidly. Every process in the industries brings out pollution. Heavy metals, especially iron ions have contaminated water resources due to industrial activity. The high concentration of iron ions is dangerous for human life. To solve this issue an activated carbon from sago pith waste was developed to remove iron ions from industrial wastewater represented by artificial iron solution. The objective of this research is to measure the adsorption capacity of sago pith waste activated carbon (SPWAC) for treating artificial iron solution. The adsorbent was carbonized at 300 °C and 80 min. Further, it was activated by citric acid 0.1 M. The treated iron solution was analyzed by condutometer to examine the iron content. Subsequently, the functional groups of SPWAC were tested via Fourier Transform Infra-Red (FTIR). The result indicates that the SPWAC can reject iron ions of more than 80 % with an iron ions concentration of 1.81 mg/L at 60 min and 300 rpm. While, FTIR analysis show alkenes, carbonyl, and hydroxyl groups are present in SPWAC. The iron ions concentration in treated water is below the allowable threshold (0.3 mg/L) based on World Health Organization (WHO) guidelines for drinking water. Therefore, the SPWAC is promising technology to be applied for treating industrial wastewater.

Importance of Locations of Iron Ions to Elicit Cytotoxicity Induced by a Fenton-Type Reaction.

Simple SummaryThe Fenton reaction generates the hydroxyl radical (•OH), which is the most reactive and toxic reactive oxygen species and widely recognized as a key player in oxidative stress. To clarify whether this highly reactive molecule travels to its biological target, the effects of the site of the Fenton reaction on cytotoxicity were investigated. Cytotoxicity induced by the Fenton reaction was affected by the distribution of iron ions surrounding and/or being incorporated into cells. Cytotoxicity was enhanced when the Fenton reaction occurred inside cells. Instead of enhancing cytotoxicity, extracellular iron ions exerted protective effects against the cytotoxicity of extracellular hydrogen peroxide in an ion concentration-dependent manner. Distance had a negative impact on the reactivity of extracellular •OH and biologically effective targets. Furthermore, an assessment of plasmid DNA breakage showed that the Fenton reaction system did not effectively induce DNA breakage.The impact of the site of the Fenton reaction, i.e., hydroxyl radical (•OH) generation, on cytotoxicity was investigated by estimating cell lethality in rat thymocytes. Cells were incubated with ferrous sulfate (FeSO4) and hydrogen peroxide (H2O2), or pre-incubated with FeSO4 and then H2O2 was added after medium was replaced to remove iron ions or after the medium was not replaced. Cell lethality in rat thymocytes was estimated by measuring cell sizes using flow cytometry. High extracellular concentrations of FeSO4 exerted protective effects against H2O2-induced cell death instead of enhancing cell lethality. The pre-incubation of cells with FeSO4 enhanced cell lethality induced by H2O2, whereas a pre-incubation with a high concentration of FeSO4 exerted protective effects. FeSO4 distributed extracellularly or on the surface of cells neutralized H2O2 outside cells. Cytotoxicity was only enhanced when the Fenton reaction, i.e., the generation of •OH, occurred inside cells. An assessment of plasmid DNA breakage showed that •OH induced by the Fenton reaction system did not break DNA. Therefore, the main target of intracellularly generated •OH does not appear to be DNA.

Prospects for the use of surface waters of the Irkutsk region for drinking water supply and the production of soft drinks

One of the urgent problems of modern civilization is the provision of the population with highquality drinking water. According to the World Health Organization (WHO), at least 5-10 % of the population suffers from waterborne diseases. According to the Federal Service for Supervision of Consumer Rights Protection and Human Well-being in nine cities of the Siberian Federal District, the influence of water quality on the formation of population morbidity (from 7,7 to 41,0 %) has been established. Analysis of the data presented in the State reports on the state and protection of the environment of the Irkutsk region showed that in the surface waters of the region there is a systematic excess of the maximum permissible concentration (MPC) for phenol, and in some controlled areas for chloroform. One of the main components used in the production of various non-alcoholic products is water. Various organic substances, such as phenols, petroleum products, halogenated derivatives of hydrocarbons, according to the requirements for the quality of water used for the preparation of soft drinks, should be absent. Therefore, the purpose of the study was the use of various adsorption systems for wastewater treatment in the Irkutsk region for drinking water supply and the production of soft drinks. Used the adsorption method. The studies were carried out on model aqueous solutions, both of individual substances and in their joint presence. Mathematical modeling of the sorption process under dynamic conditions has been carried out. As a result of the studies carried out, the possibility of using charcoal for wastewater treatment has been proven. Pretreatment of activated carbon with hydrochloric acid practically does not affect the adsorption of chloroform, but leads to an increase in the adsorption of phenol. Hydrochloric acid helps to remove iron ions from the pores of the sorbents. A decrease in the degree of water purification from phenol with an increase in pH leads to the suppression of adsorption. The effect of phenol and chloroform on the value of adsorption has been established. The sorption process is limited by external mass transfer. The discrepancy between the calculated and experimental output curves of phenol and chloroform sorption from individual solutions and in their joint presence is calculated.

Evaluation of Jordanian Natural Zeolite for Removing Iron Ions from Underground Water

Evaluation of Jordanian Natural Zeolite for Removing Iron Ions from Underground Water

Biochar from Oil Palm Frond to Reduce Fe Ions in Artificial Solution and Peat Water

Raw oil palm fronds (OPF-R) converted into biochar (OPF-B) by torrefaction processes at temperatures range of 200 °C to 300 °C. This study aims to evaluate OPF-B performance to reduce iron ions in artificial solutions and peat water. Batch adsorption carried out at room temperature by stirring (175 rpm) using an orbital shaker. Some parameters observed included optimum torrefaction temperature, optimum conditions of Fe ions adsorption (optimum pH and contact time) and sorption isotherm. Metal content measured using atomic absorption spectroscopy (AAS). Functional groups on material surface characterized using Fourier Transform Infrared (FT-IR). Torrefaction at 260 °C produces biochar with the highest efficiency in removing iron ions. Both functional groups C=O and C-O attributed to lignocellulose on OPF-B were diminished and absorption band of aromatic (C=C) increased which caused by torrefaction. The optimum conditions for removal of Fe ions at pH 5 and 30 minutes contact time. Adsorption process follows the Langmuir Isotherm which indicates the formation of a monolayer with qmax 111.11 mg/g. Amount of 0.025 g OPF-B able to reduce iron concentration from 13.960 mg/L to 0.746 mg/L in 100 mL peat water (has complied with Indonesian clean water standard for iron concentration).

Dynamic experiment on de-fluoridation of Manganese-loaded Activated Alumina

This work used Manganese-loaded Activated Alumina (MAA) as the adsorbent to analyze the effect of column height and filtration rate on the removal of fluoride and iron ions, and clarified the fluoride removal mechanism by using dynamic experiments when the fluoride and iron in drinking water exceed the standard at the same time. The results showed that the height of the column and the filtration rate have a significant impact on the operation of the system. It was the best operating condition for the system that the filtration rate was 1m/h and the column height was 300mm. After the system run for 102 hours, the fluoride ion effluent concentration exceeded the standard, which was 1.02mg / L; the concentration of iron ions in the effluent reached the standard stably after the system run for 1 hour, and the concentration was not more than 0.18mg/L. When the filtration rate was 1m/h and the column height was 150mm, the stable running time of fluoride removal of MAA column was 2.5 times that of ordinary activated alumina (AA); the start-up time of MAA to remove iron ions was one-twelfth of AA. The effect of removing fluoride and iron by MAA was significantly better than AA.

Preparation of electrospun magnetic polyvinyl butyral/Fe2O3 nanofibrous membranes for effective removal of iron ions from groundwater

AbstractRemoving iron ions from groundwater to purify, it is a challenge faced by countries across the globe, which is why developing polymeric microfiltration membranes has garnered much attention. The authors of this study set out to develop nanofibrous membranes by embedding magnetic Fe2O3 nanoparticles (MNPs) into polyvinylbutyral (PVB) nanofibers via the electrospinning process. Investigation was made into the effects of the concentration of the PVB and MNPs on the morphology of the nanofibers, their magnetic properties, and capacity for filtration to remove iron ions. The fabrication and presence of well‐incorporated MNPs in the PVB nanofibers were confirmed by scanning electron microscopy and transmission electron microscopy. Depending on the concentration of the MNPs, the membranes exhibited magnetization to the extent of 45.5 emu g−1; hence, they exceeded the performance of related nanofibrous membranes in the literature. The magnetic membranes possessed significantly higher efficiency for filtration compared to their nonmagnetic analogues, revealing their potential for groundwater treatment applications.

Removal of iron from wastewater using a hybrid filter

Limestone is originally generated from sedimentary rocks that are mainly made from CaCO3, the latter in turn is made from calcites and aragonites. This chemical composition of limestone makes it a suitable material for water/wasters treatment as these elements are identified for their capability to adsorb several pollutants. Although, limestone is environmentally sustainable material and is broadly applied in water filtration, it is has a moderate affinity for heavy metals. Thus, due to this serious drawback, limestone becomes less attracting for researchers. Therefore, this study is aiming at producing an environmentally sustainable filtration system by mixing limestone and activated carbon, and applies it to remove heavy metal (iron) from synthetic wastewaters. The ability of the new filtration media, which was made of 50% activated carbon and 50% limestone (1:1 ratio), to remove iron from 10 mg/L synthetic iron solution. The latter was created using ferrous sulphate heptahydrate and deionised water. The removal of iron was optimised for the influence of the absorbent dosage (AD) (500-1000 g), detention time (DT) (10-120 minutes) and pH of solution (4-10). The outcomes of the experiments evidenced the capacity of the new filter to efficiently remediate wastewater from iron. Where, 1000 g of this filter needed only 95 minutes, at pH of 6.0, to completely remove iron ions from the synthetic solution.

Formation of mine water composition and analysis of treatment methods

Formation of mine water inflow compositions is discussed, and the methods of mine water treatment are described. Mine water has different chemistry depending on hydrological, geological and geotechnical factors, as well as on depth of mining. Formation of mine water on higher horizons takes place under the influence of oxidation processes, while reduction processes are typical of lower levels. With an increasing depth, hydrocarbonate water changes into carbonate-sulfate and sulfate-hydrocarbonate water. The main pollutants of mine water are identified, the methods of mine water treatment are reviewed, the criteria of application of mine water treatment methods are specified, and the advantages and disadvantages of the methods are described. In terms of the Kirov Mine, the structure of mine water treatment facilities is considered. It is found that equipment included in the process flow chart ensure good removal of various size suspended solids from water and partially remove iron ions (when its oxidation goes to an insoluble form). However, some heavy metals remain in mine water. This fact is proved by the background concentrations observed in the places of mine water discharge in the Inya river. In the Inya water river, some contaminants exceed MAC, namely, total iron, manganese, copper, ion nitrite, etc. The authors describe the treatment methods and equipment used in coal mines in Kuzbass. There is a wide range of mine water treatment methods, but the technologies in application mainly reduce to mechanical purification which enables efficient removal of suspended solids, oil products, bacterial pollution and, partly, iron. In compliance with the requirements to mine water treatment quality, mines should modernize treatment facilities and introduce new advanced technologies, i.e. provide an integrated solution of the mine water treatment problem, and should anticipate usability of treated mine water and dregs.

A Study of Using Natural Sorbent to Reduce Iron Cations from Aqueous Solutions.

Iron is an essential trace element, but at high doses, this element may pose a health risk. Wastewater from iron ore mining, steel production, and metal processing, among other heavy metals, also contains high concentrations of iron (Fe3+). The use of sorption on natural materials is a potential alternative to conventional methods for removing iron ions, also because of low cost. The methods presented in this article are based on the study of kinetic properties and the acquisition of adsorption isotherms, which are one of the most important characteristics of adsorption mechanisms. The course of sorption is analyzed according to the Freundlich sorption isotherm model. Isotherm parameters are evaluated using experimental results of ferric cation sorption. The results presented relate to the investigation of natural zeolite-clinoptilolite as a ferric cation sorbent, providing a measurement of the sorption kinetics as well as the observed sorption parameters of iron cations from aqueous media. The optimal time for equilibrium in the adsorption system is determined from the kinetic dependencies. The dependence of the achieved equilibrium concentration on the initial concentration of the solution was also expressed, both graphically and analytically. The new prediction model was compared with the traditional Freundlich model. Finally, adsorption isotherms tested under laboratory conditions for a practical application can be recommended for the preliminary examination of the possible technological use of natural zeolite in the wastewater treatment process.

Removing Iron Ions Contaminants from Groundwater Using Modified Nano-Hydroxyapatite by Nano Manganese Oxide

In this article, we study modified nano-hydroxyapatite (HAp) by nano manganese oxide (Mn3O4) as adsorbent material to remove iron ions from groundwater. Different parameters were studied to option optimum conditions of removing such as contact time, pH, initial concentration, a dosage of adsorbent, agitation speed and temperature. Kinetics studies included first order (R2 = 0.915), pseudo-first order (R2 = 0.936), second order (R2 = 0.948), pseudo-second order (R2 = 0.995), Elovich equation model (R2 = 0.977), intraparticle diffusion (R2 = 0.946), Natarajan and Khalaf (R2 = 0.915) were carried out, the obtained results revealed that the pseudo-second order is the best to describe the adsorption process because the correlation coefficient is approaching one (R2 = 0.995). Adsorption isotherm was calculated by using Freundlich, Langmuir and Temkin constants, adsorption capacity from Langmuir model was 0.606 mg/g. Thermodynamic parameters (ΔG, ΔH = −51 KJ/mol, and ΔS = −142 (KJ/mol)) for the adsorption process were also calculated and discussed.