Initial Iron Concentration Research Articles

Effect of Iron Contamination and Polysilicon Gettering on the Performance of Polysilicon‐Based Passivating Contact Solar Cells

ABSTRACTOver the past decade, silicon solar cells with carrier‐selective passivating contacts based on polysilicon capping an ultra‐thin silicon oxide (commonly known as TOPCon or POLO) have demonstrated promising efficiency potentials and are regarded as an evolutionary upgrade to the PERC (passivated emitter and rear contact) cells in manufacturing. The polysilicon‐based passivating contacts also exhibit excellent gettering effects that relax the wafer and cleanroom requirements to some extent. In this work, we experimentally explore the impact of bulk iron contamination and polysilicon gettering on the passivation quality of the polysilicon/oxide structure and the resulting solar cells performance. Results show that both n‐ and p‐type polysilicon/oxide passivating contacts are not affected by iron gettering, demonstrating robust and stable passivation quality. However, for a very high bulk iron contamination (1 × 1013 cm−3), the accumulated iron in the p‐type lightly boron‐doped emitter in crystalline silicon would degrade the emitter saturation current density. This can cause a reduction in both open‐circuit voltage and short‐circuit current. Meanwhile, this very high iron content (1 × 1013 cm−3) can further degrade the fill factor and temperature coefficient of the cells. On the other hand, for an initial iron content of 2 × 1012 cm−3, which should be well above the iron level in the current industrial Czochralski silicon wafers, the resulting cells demonstrate similar performance as the control group with no intentional iron contamination. This work brings attention to both the benefits of polysilicon gettering effects as well as the potential degradation due to the accumulation of metal impurities in the p‐type emitter region.

Using Sugarcane Bagasse as an Adsorbent Material to Remove Iron from Water

This study evaluates the effectiveness of chemically treated sugarcane bagasse as an adsorbent for iron removal from water. The bagasse was modified using sodium hydroxide and citric acid, and its adsorption capabilities were characterized [1-3]. Batch adsorption experiments were conducted to determine the impact of initial iron concentration, contact time, pH, and adsorbent dosage. Results indicated that the treated sugarcane bagasse exhibited a significantly higher iron adsorption capacity compared to the raw material, with an enhancement factor of 1.7. Optimal conditions were identified as a contact time of 100 minutes, a pH of 3, and an adsorbent dosage of 1.5 grams. Adsorption isotherms were best described by the Langmuir model, yielding a maximum adsorption capacity (qmax) of 15.57 mg/g. Additionally, dynamic adsorption tests showed that the adsorbent could be reused effectively, with a desorption efficiency of 75.20%. These findings demonstrate that chemically treated sugarcane bagasse is a viable, cost-effective, and environmentally friendly option for iron removal in water treatment [4].

Influence of Technological Factors on the Formation and Transformation of Iron-Containing Phases in the Process of Ferritization of Exhausted Etching Solutions

Every year, metallurgical enterprises generate a massive amount of toxic exhausted high-concentration etching solutions. Application of the ferritization process to recycle exhausted etching solutions can help to prevent environmental pollution. It enables a cost-efficient use of water at an industrial plant and allows the plant to obtain products from toxic industrial waste and utilize it. The aim of the study was to analyze the qualitative and quantitative composition of the formed sediment and its grain size composition. Variable study parameters were the initial pH values of the solutions, the initial concentrations of total iron, and the duration of the aeration process of the reaction mixture. Thermal activation and alternating magnetic fields were used to activate the ferritization. The XRD showed that the formed sediments contained phases of γ-FeOOH, δ-FeOOH, Fe3O4, and γ-Fe2O3. Granulometry analysis showed that these sediments were highly dispersed and heterogeneous. Chemically stable phases of magnetite were obtained in the composition of sediments, with an initial concentration of iron in the reaction mixture of 16.6 g/dm3, a pH of 11.5, and a process duration of 15 min. The study results demonstrated the feasibility of further study and possible use of such sediments with a high magnetite content for the production of materials with ferromagnetic and sorption properties.

Study on bioleaching behavior of sphalerite from lead concentrate in agitator tank

Sphalerite which is highly continuous with galena cannot be effectively separated by flotation, the extraction of zinc from sphalerite in bioleaching process has become an alternative method. By testing the initial iron concentration, pulp density, grinding fineness and other parameters as well as monitoring pH, potential and dissolved oxygen, the zinc content of the lead concentrate decreased from 8.41% to less than 1% after bioleaching in 8L agitator tank. The initial concentration of ferric is the most significant factor affecting the zinc extraction efficiency of sphalerite, and when the concentration of ferric ions reaches 9g/L, acceptable leaching yield can be achieved.

ADSORPTION OF IRON(III) IONS FROM SULFURIC ACID SOLUTIONS BY DOWEX G-26 RESIN (Н)

The adsorption of iron (III) from sulfuric acid solutions on a strongly acidic cation-exchange resin Dowex G-26 (H) has been studied. The factors influencing the adsorption of iron (III) have been investigated: solution pH, contact duration, adsorbent dose, initial concentration of iron (III) in solution. The obtained results show that Dowex G-26 (H) resin has a high exchange capacity for iron (III) ions from sulfuric acid solutions. Complete adsorption of iron (III) was achieved at pH2 (99%). Based on the experimental results, Langmuir and Freindlich adsorption isotherms have been constructed. Both isotherms fully describe the adsorption of iron(III) by the Dowex G-26 adsorbent. However, a comparison of the Langmuir correlation coefficient (R2=0.9098) with respect to Freundlich (R2=0.9915) shows that the Freundlich isotherm provides a better fit than the Langmuir isotherm. Quantitative and quantitative sorption properties of Dowex G-26 (H) relative to iron (III) have been investigated using scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS). The maximum adsorption capacity (qm) for iron (III) was 166 mg/g at 250C. It has been shown that Dowex G-26(H) can be recommended as an adsorbent for sorption of Fe(III) from acidic solutions

Investigation of the solid oxidizer effect on the metal geotechnology efficiency

Purpose. The research is aimed at increasing the useful component content in a pregnant solution during in-situ leaching (ISL) using a solid oxidizer and increasing the ferric iron concentration in the leaching solution based on laboratory research. Methods. Laboratory research is performed on a specially developed model electrolyzer for obtaining comparative data on divalent iron oxidation to trivalent iron and the change in the useful component content in a pregnant solution. Firstly, tests are conducted with a basic leaching solution, then on the oxidation of the leaching solution with a solid oxidizer in the form of a lead dioxide plate. Tests are conducted by changing sulphuric acid concentration within 5-50 g/l, amount of divalent iron ions in the solution from 0.5 up to 4.0 g, lead dioxide plate surface area from 19 to 76 cm2. The leaching time is up to 10 hours. Findings. The results of laboratory research on determining the oxidation degree of divalent iron ions and change in the oxidation-reduction potential (ORP) depending on the sulphuric acid concentration and on the initial concentration of divalent iron ions in the initial solution are presented. With a change in the sulphuric acid concentration from 5 to 50 g/l, the oxidation value of divalent iron ions increases from 26.5 to 96.5%, and with an increase in the initial solution concentration of divalent iron, the oxidation degree of divalent iron naturally decreases from 95.2 to 58.8%. In the initial leaching solution, the divalent solution concentration is 312 mg/l, and that of the trivalent solution is 288 mg/l. After oxidation with a solid oxidizer, the divalent and trivalent iron concentrations are 56 and 392 mg/l, respectively. In the course of further laboratory research using core materials from a uranium deposit, it has been revealed that when leaching with a basic solution, the uranium content in the pregnant solution is 19.36 mg/l, and when leaching with a solution after oxidation with a solid oxidizer, it is 27.9 mg/l, which is by 8.54 mg/l more. Originality. New dependences have been determined of the oxidation degree of divalent iron ions to trivalent one on the sulphuric acid concentration and on the initial concentration of divalent iron ions, as well as the useful component content in the pregnant solution on the leaching time when using a solid oxidizer. Practical implications. Using of a solid oxidizer, it is possible to increase the trivalent iron concentration in the leaching solution and the useful component content in the pregnant solution compared with the basic technology, thereby reducing the time of mining uranium reserves. Proposed technology is environmentally friendly, with low capital costs.

Fenton oxidation treatment of benzalkonium chlorides to prevent antibiotic resistance development in non-acclimated activated sludge system

Improper discharge of benzalkonium chlorides (BAC) to sewage and wastewater treatment plants can cause acute intoxication and chronic low-dose exposure, which can lead to changes in microbial communities and can promote the development of antibiotic resistance. The aim of this study was to develop a feasible treatment strategy based on the homogeneous Fenton oxidation to minimize the negative impact of BAC-containing wastewater on activated sludge systems. The effect of initial iron and oxidant concentrations was analyzed. After an initial Fenton oxidation stage (180 min), the solution needed to be stored at ambient temperature and in the dark for some time to remove residual oxidizing agents and promote further oxidation. The 0.1 % w/v-BAC solution treated at best operating conditions, i.e., homogeneous Fenton for 180 min at 30 °C, pH0 = 3, stoichiometric oxidant dose, [Fe+2]0:[H2O2]0 = 0.011, and stored during 4 days, led to BAC conversion of 99.9 %, no residual H2O2, no sludge, and DOC conversion of 40.8 %. An increase in metabolic activity was observed when non-acclimated activated sludge was exposed to the treated solution. Treated solution showed biodegradation without increasing resistance to Ampicillin, Cephalexin, or Ciprofloxacin. Evaluation of the effect of water matrix (tap or distilled) showed that the composition of tap water enhanced the oxidation extent, resulting in a 15 % increase in mineralization and a further reduction of COD. This study provides insights into the treatment of wastewater containing BAC and its safe discharge to sewage systems or biological wastewater treatment plants.

Experimental study on the performance of the dielectric barrier discharge technique in the treatment of simulated groundwater with high iron and manganese content

Abstract Groundwater with high concentrations of iron and manganese is harmful to the human body and modern industries. Conventional methods of treating iron and manganese have the disadvantage of high costs and complex control processes. A dielectric barrier discharge (DBD) water treatment system was built to remove iron and manganese from groundwater in this paper. Single-factor experiments were used to analyze the effect of discharge power, initial iron and manganese concentrations, gas flow rate, liquid flow rate, initial pH, flocculant and capture agent process parameters on iron and manganese removal rates. It was found that Fe2+ removal rates can reach 97.31% and Mn2+ removal rates can reach 81.42% when the initial concentrations of Fe2+ and Mn2+ are 6 and 3 mg/L, respectively. The use of 10 mg/L NaHCO3 or 5 mg/L Ca(OH)2 increased the removal rate of Fe2+ to 99% but had no effect on the removal rate of Mn2+. It was found that the optimum treatment time for Mn2+ was different for different process parameters, mainly in the range of 9–15 min, which needs to be noted in future production applications. This work shows that DBD can effectively remove iron and manganese ions from groundwater and analyzes the removal mechanism.

Exploring the scalability of solar-activated persulfate with iron-EDDS in raceway pond reactors for advanced wastewater treatment

In this study, the removal of microcontaminants (MCs) by the activation of persulfate (PS) with Fe(III)-EDDS under natural solar radiation in a low-cost raceway pond reactor (RPR) was investigated. The primary focus was to evaluate the effect of the Fe(III)-EDDS molar ratio, initial iron concentration, PS concentration, and initial pH on process performance while using sulfamethoxazole (SMX) and carbamazepine (CBZ) as model MCs. The investigation encompassed three different water matrices: natural water, synthetic municipal wastewater treatment plant (MWWTP) secondary effluent, and actual MWWTP secondary effluent. During experiments in natural water, it was found that 0.1 mM Fe(III) at a 1:2 molar ratio and 0.2 mM Fe(III) at a 1:1 molar ratio resulted in the most adequate operational conditions. Further experiments revealed a general decrease in process efficiency due to water matrix effects; however, this could be compensated by increasing the initial PS concentration and decreasing the initial operation pH. For example, the use of 0.2 mM Fe(III) at a 1:1 Fe(III):EDDS molar ratio, with 2 mM PS at pH 6, allowed for an 80% removal of the MCs sum in approximately 20 min, along with a significant decrease in chronic toxicity (Selenatrum Capricornutum) when working with actual waters. Nonetheless, the final experiment, focused on simultaneous MCs removal and wild bacteria inactivation in actual MWWTP secondary effluent, showed only a 1.6–1.8 log reduction of Escherichia coli, total coliforms, and Enterococcus faecalis. As such, further studies about the solar/Fe(III)-EDDS/PS process are needed to explore new strategies that improve its disinfection efficiency.

Unlocking the hidden value of industrial by-products: Optimisation of bioleaching to extract metals from basic oxygen steelmaking dust and goethite

In this study, the potential of bioleaching to extract valuable metals from industrial by-products, specifically basic oxygen steelmaking dust (BOS-D) and goethite was investigated. These materials are typically discarded due to their high zinc content and lack of efficient regeneration processes. By using Acidithiobacillus ferrooxidans, successful bioleaching of various metals, including heavy metals, critical metals, and rare earth elements was achieved. The Taguchi orthogonal array design was used to optimise the bioleaching process, considering four variables at three different levels. After 14 days, the highest metal extraction for the BOS-D (11.2 mg Zn/g, 3.2 mg Mn/g, 1.6 mg Al/g, 0.0013 mg Y/g, and 0.0026 mg Ce/g) was achieved at 1% solid concentration, 1% energy source concentration, 1% inoculum concentration, and pH 1.5. For goethite, the optimal conditions were 1% solid concentration, 4% energy source concentration, 10% inoculum concentration, and pH 2 resulting in a extraction of 26.6 mg Zn/g, 2.1 mg/g Mn, 1.8 mg Al/g, 0.01 mg Co/g, 0.0022 mg Y/g. These findings are significant, as they demonstrate the potential to extract valuable metals from previously discarded industrial by-products. The extraction of such metals can have substantial economic and environmental implications, while simultaneously reducing waste in the metallurgical industry. Furthermore, the preservation of initial concentration of iron in both BOS-D and goethite residues represents a significant step towards implementing more sustainable industrial practices.

Developing of a Counter-Current Copper Leaching Process Using Response Surface Methodology

ABSTRACT Due to the scarcity of water in many parts of the world, wastewater generated by hydrometallurgical processes has been recognized as a valuable resource for recovery or reuse. A method for reusing hydrometallurgical raffinate in the leaching of low-grade oxide copper ore in a counter-current leaching process was evaluated. In the first stage of the investigation, the influential factors on copper leaching, such as the amount of acid consumed (200–400 g/kg of ore), the initial iron concentration of the raffinate (5–25 g/L), the liquid-to-solid ratio (2–10 mL/g), and the duration of the leaching process (15–75 min), were examined using response surface methodology coupled with central composite design. Two responses, copper recovery and final copper concentration, were selected to determine the optimal conditions for the leaching process. Based on the statistical model, it was found that using 325 g/kg of ore of consumed acid, an initial iron concentration of 10 g/L, a liquid-to-solid ratio of 4 mL/g, and a leaching time of 60 min would result in higher values for both responses. Confirmation runs were conducted to validate the selected conditions and the suitability of the statistical model. Additionally, compositional and morphological characterization of samples before and after the leaching process was conducted using field diffusion scanning electron microscopy and X-ray diffraction analysis, which showed the dissolution of compounds such as tenorite and cuprite. In the second stage, a two-unit counter-current leaching system was adopted, as hydrometallurgical processes are usually carried out in multiple stages on an industrial scale. This leaching system was designed to maximize copper dissolution by considering the information obtained from the response surface methodology. The use of this leaching system increased the overall leaching efficiency by up to 80%. By characterizing the solid samples, it was found that the copper extraction percentage in a counter-current leaching system could be increased by simultaneously precipitating iron-bearing compounds.

Perancangan Multiple Tray Aerator Sebagai Pretreatment Proses Reverse Osmosis untuk Pengolahan Air Baku Sungai Itik Kabupaten Kubu Raya

The Itik River is used by the community as a source of clean water for daily needs such as bathing and washing, the characteristics of the Itik River water do not meet the requirements for water based on PERMENKES No. 32 of 2017. The characteristics of the Itik River water have the parameter Iron (Fe) 1.15 mg/ l which exceeds the quality standard. The design of multiple tray aerators is expected to reduce iron in the Itik River raw water to meet water standard requirements before entering the reverse osmosis process. The method used to reduce iron (Fe) in water is aeration with multiple tray aerators. Initial sample concentration of iron (Fe) 3.22 mg/l, TDS 844 mg/L, pH 7.1 and DO 6.0. The design of multiple tray aerators consists of design calculations, design making, preparation of tools and materials, and the tool building process. The multiple tray aerator is designed to have a capacity of 1000 l/day with 5 tiers of trays. Multiple tray aerator dimensions: length = 1.5 m, width = 1.3 m, height = 4.3 m. The distance between each tray is 60 cm, the number of holes per tray is 1,512, the hole diameter is 4 mm, and the distance between holes is 2 cm. The results of water treatment obtained a decrease in concentration (Fe) of 94.44%, TDS became 838 mg/L, pH became 7.9 and DO 6.9 mg/l. The total RAB needed to build multiple tray aerators made of iron is Rp. 4,380,000.

BIOKINETIC CHARACTERIZATION OF FERROPLASMA ACIDIPHILUM

Abstract. Recently a mixed culture dominated by the iron-oxidizing microorganisms Leptospirillum and Ferroplasma has been used in a large-scale microbial fuel cell for electrical power generation. There are many factors that affect the kinetics of iron oxidation by the mixotroph Ferroplasma acidiphilum. This study investigated the effects of pH, temperature, and substrate and yeast extract concentrations in order to arrive at kinetically favorable operating conditions with minimal jarosite precipitation. Furthermore, F. acidiphilum was cultured with Leptospirillum sp. in order to determine its viability as a species capable of limiting the organic by-products of chemolithotrophic microbial growth. Bacterial characterization in the culture was accomplished using fluorescent in situ hybridization (FISH). It was found that the ferrous iron oxidation was most favorable at yeast extract concentration of 0.02% (w/v), pH of 1.6, temperature of 35 oC and an initial ferrous iron concentration of 1 g/L yielding a maximum specific growth rate of 0.0351-0.042 h-1. Moreover, F. acidiphilum displayed a symbiotic relationship with its chemolithotrophic counterpart, Leptospirillum sp. in that they were able to utilize the metabolic organic products of the chemolithotroph and limit the organic concentration to ~20 ppm total organic carbon (TOC), well below the threshold concentration of 250 ppm for chemolithotroph activity.

Composition dependence of the specific heat of FeSi

Recently, a high-mobility surface conduction channel and in-gap states were identified in the correlated small-gap semiconductor FeSi using electrical transport measurements and high-resolution tunneling spectroscopy. The mobility of the charge carriers in the surface channel is quantitatively reminiscent of topological insulators, but displays a lack of sensitivity to the presence of ferromagnetic impurities as studied by means of a series of single crystals with slightly different starting compositions. Here, we report measurements of the specific heat of these crystals. At low temperatures, a shallow maximum is observed in the specific heat divided by temperature. This maximum is suppressed under magnetic field, characteristic of a Schottky anomaly associated with magnetic impurities. In comparison, the height of this maximum decreases with increasing initial iron content.

Feasibility of successive hydrogen and methane production in a single-reactor configuration of batch anaerobic digestion through bioaugmentation and stimulation of hydrogenase activity and direct interspecies electron transfer

Two-stage anaerobic digestion is a promising way to increase the efficiency of decomposition of organic waste. However, spatial separation of stages makes this technology less economically attractive. In this work, we studied a model of two-stage anaerobic digestion with stages separated in time in one reactor. To implement this model, we used a combination of (1) bioaugmentation with a hydrogen-producing Thermoanaerobacterium thermosaccharolyticum SP-H2, resistant to low pH, (2) setting a low initial pH (5.5) to reduce the activity of hydrogenotrophic methanogens, (3) supplementing additives in the form of soluble iron (II) and granular activated carbon (GAC) to stimulate hydrogenase activity and direct interspecies electron transfer (DIET), respectively. For comparison, two methanogenic inoculums with different dominant microbial groups and initial iron concentrations were used. With the simultaneous addition of GAC and iron (II), sequential production of hydrogen and methane was observed for both methanogenic inoculums. Without the addition of GAC, methane formation was practically not observed, which, apparently, indicated the impossibility of syntrophic degradation of acidogenesis products due to the high partial pressure of hydrogen and the absence of conductive material for activation of DIET. Significant differences in hydrogenase activity and the kinetics of hydrogen and methane formation according to the modified Gompertz equation depending on the iron content in the system may indicate the importance of this additive. Further studies should be aimed at determining the optimal initial pH, concentrations of stimulating additives, bioaugmentation and methanogenic cultures, as well as confirming the stability of the proposed single-reactor two-stage anaerobic digestion system in semi-continuous mode.

Synergistic effect of Fenton oxidation and adsorption process in treatment of azo printing dye: DSD optimization and reaction mechanism interpretation

ABSTRACT The main challenges to overcome within the Fenton process are the acidic pH as an optimal reaction condition, sludge formation in neutral pH medium and high toxicity of treated printing wastewater due to the generation of contaminating by-products. This research discusses the catalytic activity of homogeneous (FeSO4/H2O2) and heterogeneous (Fe2(MoO4)3/H2O2) Fenton processes in treatment of Yellow azo printing dye in synthetic aqueous solution and real printing effluent, with an integration of adsorption on functionalized biochar synthesized from wild plum kernels. The definitive screening design (DSD), was used to design the experiment. Independent variables were initial dye concentration (20–180 mg L−1), iron concentration (0.75–60 mg L−1), pH (2–10) and hydrogen peroxide concentration (1–11 mM). Higher decolourization efficiency of 79% was obtained within homogeneous Fenton treatment of printing wastewater, in comparison to heterogeneous Fenton treatment (54%), after a reaction time of 60 min. Same trend of mineralization degree was established: COD removal was 59% and 33% for homogeneous and heterogeneous Fenton process, respectively. The application of adsorption treatment has achieved significant advantages in terms of toxicity reduction (95%) and decolourization efficiency (90% of TOC removal and 22% of dye removal) of treated samples, even at neutral pH medium. Degradation mechanisms within Fenton and adsorption processes were proposed based on the qualitative gas chromatography/mass spectrometry analysis, physico-chemical properties of dye degradation products and functionalized biochar. Overall, the homogeneous Fenton/adsorption combined process can be potentially used as a treatment to remove azo dyes from contaminated water.

Bio-Assisted Leaching of Non-Ferrous Metals from Waste Printed Circuit Boards—Importance of Process Parameters

The effect of varying process parameters during bio-catalyzed leaching of metals from end-of-life printed circuit boards (PCBs) was investigated. Fragmented PCBs (under 2 mm) were subjected to an indirect bioleaching in a stirred tank reactor while pulp density, pH and initial ferric iron content were varied. An iron oxidizing Acidithiobacillus ferrooxidans 61 microbial strain was used to generate the lixiviant through oxidizing Fe(II) to Fe(III). Chemically generated Fe(III) was tested as lixiviant under the same conditions as the biological one for comparative purposes. Cell enumeration during leaching and microscopic observations of the input and leached PCBs were conducted in parallel to shed light on the observed phenomena. The degree of bringing metals in solution was found to depend mainly on ferric iron concentration and pH. For the entire duration being always kept as 24 h, substantial portion of Cu (~87%) was extracted respectively at 1% pulp density (PD), 15.5 g/L Fe3+ and pH 1. For Zn and Ni, nearly 100% recovery was observed at 5% PD, 18 g/L Fe3+ and pH 1.1. The achieved results offer possibilities for further studies at higher pulp density, to ultimately render the bioleaching approach as enabling economical and environmentally friendly technology for urban mining of non-ferrous metals.

Biosorption removal of iron from water by Aspergillus niger

The expulsion of iron from water is an essential issue. Exceeding iron concentrations in water, it become more toxic and cause several troubles for human health and environment. The biosorption is the upcoming mechanism to treat the iron from wastewater. Microorganisms perform an important function in the bioremediation of wastewater. This study was conducted to investigate the removal of iron by dried biomass of Aspergillus niger (A.niger). The dried A. niger was tested as a sorbent for the removal of iron from wastewater. The effects of various experimental parameters as initial iron concentration, amount of biomass, contact time and the initial pH solution were examined and optimal experimental conditions were obtained. The obtained adsorption results were fitted to the Langmuir, Freundlich, and Temkin equations. The study showed that dried A. Niger biomass in high concentration 4 g/100 ml was found to be more effective in the removal of iron from water at pH 3 with contact time 60 min. the A. Niger successfully removed iron and has ability to be regenerated and reused in the removal process.

Formation of Iron (Hydr)Oxide Nanoparticles with a pH-Clock.

We demonstrate the autonomous synthesis of iron (hydr)oxide (green rust, magnetite, and lepidocrocite) nanoparticles by precipitating iron(II) ions using hydroxide ions generated in situ with the methylene glycol-sulfite (MGS) reaction, a pH-clock. We show that the nature of the products can be predetermined by tuning the initial iron(II) concentration.

Aeration Strategies for the Removal of Iron From Water Manufacturing Industry

Clean water used for daily needs in the industry must meet health requirements and be safe to use, but artesian well water often contains various dangerous metals, one of which is iron. This study aimed to determine the effect of various variations in the length of aeration contact time on the reduction of iron content in water. In this study, the aeration process of water with various variations in the number of aerators was carried out to reduce the iron content. This type of research was experimental research with a pre and post-test design. The population and sample in this study were partially artesian well water in the shoe industry office. The sampling technique in this study used grab sampling. The results showed the greatest decrease in iron content was in 3 aerators with an initial iron content of 1.18 mg/l after treatment to 0.15 mg/l. The results showed that reducing iron content in clean water with variations in the number of aerators reduced Fe levels. It is recommended to the shoe industry to reduce the iron content of clean water by using an aeration process using an aerator with a capacity of 5 L/second. This study found that using aerators can be effectively used as an economical method in reducing iron content in the industrial and community environment.