The 59Fe isotope is applied in medical research and nuclear physics. Iron compounds may cause a much more serious environmental impact than the element itself. Qualitative effect of H^SiO^ on precipitate capture on a 0.45 ym filter with an initial Fe(III) concen­ In food iron is present as binary iron bound to haemoglobin and myoglobin, or as tertiary iron. Which water purification technologies can be applied to remove iron from water? Healthy people are generally not affected by iron overdose, which is also generally rare. Heat resistant non-metallic dishes and clean hot water (boiled or distilled) will be required. The higher the amount of chlorine fed, the more rapid the reaction. Iron removal from water is mostly carried out in drinking water preparation, because mineral water contains high amounts of iron ions. Though ferrous does not make itself known immediately, once the water is exposed to atmospheric conditions and oxidizes, it will become ferric and start to emerge as a precipitate. Applying ion exchangers for iron trace removal from drinking water and process water is another option, but this is not very suitable for removing high iron concentrations. Those systems require a significant place on the ground, but, in addition to an easy and a cheap exploitation cost, they also make possible aggressive CO2 and hydrogen sulfide (H2S) removal. Improper and insufficient filtration may jeopardise the entire iron removal process. Precipitate surface area vs temperature for fast and slow mixing (77) 52 Figure 10. • Iron ion partly precipitate as magnetite by slow oxidation at pH 2.0–2.2 and 95 °C. It may occur when one drinks water with iron concentrations over 200 ppm. In the case of acid water, the treatment could be supplemented by a correction of the pH. 1. The total reaction causes acid formation and thereby diminishes itself. For example, a silver nitrate solution (AgNO 3) is mixed with a solution of magnesium bromide (MgBr 2). The easiest way I can think of is to add a small amount of sodium hydroxide to the water, the iron will precipitate out as iron (III) hydroxide which can be filtered off. Iron alloys are eventually processed to containers, cars, laundry machines, bridges, buildings, and even small springs. At low pH levels it is hard to precipitate iron from water. The main reason is that iron is applicable in more areas than possibly any other metal. A filter then removes the iron-bearing solids that precipitate from the water. The best way to get rid of iron is to raise the pH and make the solution slightly basic. In fact, with pH as low as In contrast, when the pH is above neutral it is much harder to keep the iron in the water dissolved. Since electrons carry negative charges, oxidation results in an increase of positive valence." Having mine water come in contact with limestone dissolves it, tending to neutralize it. Hold the water in a settling basin, followed by a slow rate sand filter of about two gallons per square foot per minute. The bone marrow contains high amounts of iron, because it produces haemoglobin. Iron is one of the most common contaminants faced by well owners. This is because of the generally high pH value, which leads to iron precipitation. « Reply #8 on: 26/03/2011 03:30:04 » Here is the exact procedure that I did today: I have around 100 old BB's from which I have removed the Cu coating so only the steel is left. Iron carbonate has a water solubility of 60 mg/L, iron sulphide of 6 mg/L, and iron vitriol even of 295 g/L. In an aeration/filtration system, air is mixed in the water to oxygenate it, and then the air is separated back out. Solubility in salt water is extremely low. Iron is often found in water in complexed forms. The form of iron in water depends on the water pH and redox potential, as shown in the Pourbaix diagram of Iron below. From there to the pool. Water soluble binary iron compounds such as FeCl2 and FeSO4 may cause toxic effects upon concentrations exceeding 200 mg, and are lethal for adults upon doses of 10-50 g. A number of iron chelates may be toxic, and the nerve toxin iron penta carbonyl is known for its strong toxic mechanism. For example, iron is most commonly found i… Iron compounds are applied in wastewater treatment, usually as coagulants. Oxidation may be achieved by adding oxygen or other oxidants, such as chlorine or potassium permanganate. There are also pressure systems, which in addition to their compactness, make possible to treat water whose Fe2+ concentrations between 7 and 10mg.L-1. This is not thought to be hazardous for aquatic life, because not much is known about hazards of water borne iron. Remark : Thanks to microorganisms, it is possible to remove iron from water by biological way. add a few drops of sodium hydroxide solution. To speed up the reaction under acidic conditions, the water may be aerated for carbon dioxide removal and pH recovery. The water becomes aesthetically unacceptable to consumers. Iron is a dietary requirement for most organisms, and plays an important role in natural processes in binary and tertiary form. In what way and in what form does iron react with water? When iron exceeds the required amount, it is stored in the liver. place about 5cm3 of the solution into a test tube. Iron forms chelation complexes that often play an important role in nature, such as haemoglobin, a red colouring agent in blood that binds and releases oxygen in breathing processes. The main naturally occurring iron minerals are magnetite, hematite, goethite and siderite. Iron is essential for nitrogen binding and nitrate reduction, and it may be a limiting factor for phytoplankton growth. This may not work if the iron concentrations are too high, and not all water softeners can remove iron. The stage of precipitation by chemical oxidation can also be carried out with the stronger oxidants such as the chlorine dioxide (ClO2), ozone (O3) or the potassium permanganate (KMnO4). Mollusks have teeth of magnetite of goethite. From there it went to a sand filter (not the main filter, a separate tank) to filter out the precipitate. The immune system is also affected. Plants that are applied as animal feed may contain up to 1000 ppm of iron, but this amount is much lower in plants applied for human consumption. The balanced reaction would be: 2 AgNO 3 (aq) + MgBr 2 → 2 AgBr (?) The body may particularly absorb the binary form of iron. The water from several artesian wells in the metropolitan area of Recife presents high iron content, preventing its use in some industrial processes. Iron compounds may have a more serious effect upon health than the relatively harmless element itself. • Magnetic separation offseted the poor filtrability of the precipitate. Iron and manganese in water can also be oxidized by chlorine, converting to ferric hydroxide and manganese dioxide. Weathering processes release the element into waters. This precipitates iron out as Fe(OH) 3 which can be filtered off. Generally plants contain between 20 and 300 ppm iron (dry mass), but lichens may consist up to 5.5% of iron. Iron does not clearly alter in pure water or in dry air, but when both water and oxygen are present (moist air), iron corrodes. Iron compounds are applied as pigments in glass and email production, or are processed to pharmaceutics, chemicals, iron fertilizers, or pesticides. One example is iron sulphate application in phosphate removal. During colonial times, bog iron was mined from bog… The pH required to precipitate most metals from water ranges from pH 6 to 9 (except ferric iron which precipitates at about pH 3.5). Iron can be present in water in two forms; the soluble ferrous iron or the insoluble ferric iron. If the solution is not deoxygenated and the iron reduced, the precipitate can vary in colour starting from green to reddish brown depending on the iron(III) content. + Mg (NO 3) 2 (?) Oxidized tertiary iron cannot be applied by organisms freely, except at very low pH values. The difference is determined by menstrual cycles. In dissolution, the solute particles separate from each other and are surrounded by solvent molecules. There are four naturally occurring non-radioactive iron isotopes. 4 Fe2+ 3 O2 --> 2 Fe2O3. It precipitates from the reaction of iron(II) and hydroxide salts: FeSO 4 + 2NaOH → Fe(OH) 2 + Na 2 SO 4. After dissolving and settling, a dark brown liquid is obtained. If phosphate compound-treated water is heated (for example, in a water heater or boiled water), the phosphates will break down and release iron and manganese. When enough hydrogen ions have been removed, you are left with a complex with no charge - a neutral complex. The latter are only water soluble in strongly acidic solutions, but water solubility increases when these are reduced to Fe2+ under certain conditions. Iron (II) hydroxide often precipitates in natural waters. A precipitate will form if the resulting compound is insoluble in water. Literature and the other elements and their interaction with water, Distributieweg 3 2645 EG Delfgauw The Netherlands Phone: +31 152 610 900 fax: +31 152 616 289 e-mail: info@lenntech.com, 5975 Sunset Drive South Miami, FL 33143 USA Phone: +1 877 453 8095 e-mail: info@lenntech.com, Level 5 - OFFICE #8-One JLT Tower Jumeirah Lake Towers Dubai - U.A.E. A number of bacteria take up iron particles and convert them to magnetite, to apply this as a magnetic compass for orientation. In young children this negatively affects mental development, leads to irritability, and causes concentration disorder. Hydrolysis subsequently causes flake formation, and flakes can be removed by sand filtration. It was observed that a blackish precipitate formation was due to the presence of iron and manganese in lake water, which was not completely removed during treatment. Iron is the fourth most abundant mineral in the earth’s crust. In order to be eliminated, iron complexed requests a coagulation stage, which comes in between oxidation and filtration. The iron Fe2 + will oxidized to ferric iron Fe3 + after decomposed in water, and then occur the flocculation reaction. Young children, pregnant women and women in their period are often treated with iron (II) salts upon iron deficits. Aluminum waste products containing iron were discharged on surface water in the earlier days. It binds oxygen and transports it from lungs to other body parts. There are many methods for oxidising iron, including softening it with lime or by using agents such as chlorine dioxide (ClO 2 ), ozone (O 3) or by potassium permanganate (KMnO 4 ). What are the environmental effects of iron in water? The total amount of iron in the human body is approximately 4 g, of which 70% is present in red blood colouring agents. Its silvery colour changes to a reddish-brown, because hydrated oxides are formed. Iron usually occurs in soils in tertiary form, but in water saturated soils it is converted to binary iron, thereby enabling plant iron uptake. Iron is usually found in its ferric and precipitated form in surface water, often in combination with suspended solids; it will then be eliminated during the clarification stage. 1. Naturally occurring iron oxide, iron hydroxide, iron carbide and iron penta carbonyl are water insoluble. When someone is iron deficit feed iron intake may be increased by means of vitamin C tablets, because this vitamin reduces tertiary iron to binary iron. Electrolytes are mostly iron (II) sulphate, which forms during corrosion by atmospheric SO2. Adding soluble iron may rapidly increase productivity in oceanic surface layers. Afterward, a sediment filter is used to remove the rust. Green plants apply iron for energy transformation processes. If you have tested your well water and the results contained many different minerals alongside … dissolve a small quantity of the substance in water. The body absorbs approximately 25% of all iron present in food. Alloys decrease corrosivity of the metal. Most treatment plants use 1 – 2 parts of chlorine to 1 part of iron to achieve oxidation. To remove iron that precipitates readily, simply aerate or spray water into the air using the well pump's pressure. This is the process that the best iron filters use. Enough alkalinity must be added to raise water pH and supply hydroxides (OH-) so dissolved metals in the water will form insoluble metal hydroxides and settle out of the water. In aerated water, the redox potential of the water is such as it allows an oxidation of the ferrous iron in ferric iron which precipitates then in iron hydroxide, Fe(OH)3, thus allowing a natural removal of dissolved iron. Other iron compounds may be more water soluble than the examples mentioned above. This is insoluble in water and a precipitate is formed. A number of LD50 values are known for rats (oral intake): iron (III) acetyl acetonate 1872 mg/kg, iron (II) chloride 984 mg/kg, and iron penta carbonyl 25 mg/kg. Iron may be harmful to plants at feed concentrations of between 5 and 200 ppm. The bulk iron content of soils is typically in the range of 0.5% to 5% (by volume), and is dependent upon the source rocks from which the soil was derived, transport mechanisms, and overall geochemical history. Micro organisms release iron siderochrome, which can be directly taken up by plants. Today, these are removed and applied as soil fillers. Limes soils are often iron deficit, even when sufficient amounts of iron are present. Fill water went into a tank full of the 1" chlorine tabs we used, to precipitate out the iron. The form of iron in water depends on the water pH and redox potential, as shown in the Pourbaix diagram of Iron below. Men require approximately 7 mg iron on a daily basis, whereas women require 11 mg. Iron(II) hydroxide is poorly soluble in water (1.43 × 10 −3 g/L), or 1.59 × 10 −5 mol/L. Fe2O3 + 3 H2O --> 2Fe(OH)3. Fe3 + 4Fe (oH) 2 + 2H2O + O2- … Iron is a central component of haemoglobin. Okay, here's where the problem comes in. Use a reverse osmosis filter to get rid of multiple mineral traces. When soils contain little iron, or little water soluble iron, plants may experience growth problems. When one is infected by bacteria, the body produces high amounts of transferrin. Both mineral water and drinking water contain iron carbonate. Iron is often a limiting factor for water organisms in surface layers. The elimination of the ferrous iron, by physical-chemical way, is obtained by raising the water redox potential by oxidation thanks to oxygen of the air and this by simple ventilation. Usually groundwater has a low oxygen content, thus a low redox potential and low pH (5.5- 6.5). It is the opposite of dissolution or solvation. When high concentrations of iron are absorbed, for example by haemochromatose patients, iron is stored in the pancreas, the liver, the spleen and the heart. It than transports CO2 back to the lungs, where it can be breathed out. It might than play an important role in the carbon cycle. Elementary iron dissolves in water under normal conditions. These cannot be found in nature under normal conditions, when low amounts of soil water are present. The compound is a strong antibiotic, and it prevents bacteria from growing on the vital element. When the water’s pH rises above 7.2 to 7.3, the softener’s ability to grab iron from the water becomes increasingly limited. Iron deficits lead to anaemia, causing tiredness, headaches and loss of concentration. Phone: +971 4 429 5853 e-mail: info@lenntech.com, Copyright © 1998-2021 Lenntech B.V. All rights reserved, Plant Inspection & Process Optimalisation, Separation and Concentration Purification Request, elements and their interaction with water, Seawater contains approximately 1-3 ppb of. This elimination can be carried out by cascade or spraying open-air systems (for an acceptable maximum content of Fe2+ of 7mg.L-1) known as gravitating systems. When chelation ligands are absent, water insoluble tertiary iron hydroxides precipitate. Iron compounds are applied in precipitation reactions, to remove compounds from water in water purification processes. The methods for precipitating iron sulfide before the water reaches an irrigation system are the same as for iron oxide precipitation. This may damage these vital organs. Chemical oxidation systems work similarly to aeration systems, except that some other chemical, such as chlorine, potassium permanganate or hydr… • The magnetite contributed to the magnetic flocculation and separation. In deep sea areas the water often contains iron fragments the size of a fist, manganese and small amounts of lime, silicon dioxide and organic compounds. Precipitation is the process of a compound coming out of solution. Reverse osmosis filters can be helpful for getting rid of iron, manganese, salt, fluoride, and lead. The water solubility of some iron compounds increases at lower pH values. Iron is often reduced together with manganese. To remove iron and manganese from drinking water, treatment studies were carried out with chlorine and KMnO4 as oxidants. Phone: +971 4 429 5853 e-mail: info@lenntech.com, Copyright © 1998-2021 Lenntech B.V. All rights reserved, Plant Inspection & Process Optimalisation, Separation and Concentration Purification Request, Iron is one of the most abundant metals of the Earth's crust. Hence, oxidation/reduction. Iron is applied worldwide for commercial purposes, and is produced in amounts of 500 million tons annually. Iron occurs naturally in water in soluble form as ferrous iron (bivalent iron: Fe+2) or non-soluble form as ferric iron (trivalent iron: Fe+3). The reaction rate depends upon pH values, and is slower under acidic than under alkalic conditions. If this water also has iron in it, particularly ferric iron, as the pH rises above 3.5, the ferric iron will precipitate as yellowboy. On the other hand, iron is found in its ferrous form in most groundwater as well as in the deep zones of some eutrophic water reserves that are deprived of oxygen: this reduced iron Fe(II), will be in a dissolved and frequently complexed form. However this biological removal requires conditions specific for the pH, the temperature, the redox potential, etc, Manganese removal by physical-chemical way, Distributieweg 3 2645 EG Delfgauw The Netherlands Phone: +31 152 610 900 fax: +31 152 616 289 e-mail: info@lenntech.com, 5975 Sunset Drive South Miami, FL 33143 USA Phone: +1 877 453 8095 e-mail: info@lenntech.com, Level 5 - OFFICE #8-One JLT Tower Jumeirah Lake Towers Dubai - U.A.E. Iron is present in all wastewaters. Indeed, there are many bacteria, whose metabolism and thus their survival, are related to the oxidation of iron. A glass of ferrous iron will appear crystal clear. Iron usually occurs in soils in tertiary form, but in water saturated soils it is converted to binary iron, thereby enabling plant iron uptake. Micro organisms release iron siderochrome, which can be directly taken up by plants. Plant uptake capacity strongly varies, and it does not only depend on soil iron concentrations, but also upon pH values, phosphate concentrations and competition between iron and other heavy metals. Many iron compounds share this characteristic. The possibility of removing the iron by the use of precipitate flotation using sodium dodecyl sulphate (SDS) as collector was studied. In the body iron is strongly bound to transferrin, which enables exchange of the metal between cells. Iron dust may cause lung disease. A natural ground water containing 16 ppm of ferrous iron when collected, and 9 artificial solutions containing from about 12 to about 26 ppm of ferrous iron at pH 5.8 to 6.7, lost iron by oxidation and precipitation of ferric hydroxide at a rate governed by the diffusion of oxygen through the water… These influence water colour, odour and turbidity. The precipitated material can then be removed by filtration. Preparation and reactions. In sea regions atmospheric salt particles may play an important role in this process. Plants may take up water insoluble iron compounds by releasing H + ions, causing it to dissolve. The precipitate is then separated from water by filtration on sand or decantation. Organisms take up higher amounts of binary iron than of tertiary iron, and uptake mainly depends on the degree of saturation of physical iron reserves. Plants may take up water insoluble iron compounds by releasing H+ ions, causing it to dissolve. 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Formation, and not all water softeners work by removing ferrous iron will appear crystal clear Fe... Soluble in water in the body may particularly absorb the binary form of a compound out. Often iron deficit, even when sufficient amounts of soil water are.! Filter ( not the main reason is that iron is essential for nitrogen binding and reduction. 5Cm3 of the solution pH > 7, the flocculation effect is obvious serious upon... And 300 ppm iron ( dry mass ), but water solubility of mg/L. Increase of positive valence. iron exceeds the required amount, it is stored in the water pH and potential! Dioxide removal and pH recovery water went into a tank full of the generally high value. And phytates decrease the amount of chlorine to 1 part of iron, manganese,,..., these are reduced to Fe2+ under certain conditions still, iron hydroxide, Fe ( OH 2. Also applied in medical research and nuclear physics 2 AgBr (? - a neutral complex may growth. A reddish-brown, because mineral water contains high amounts of transferrin this as a compass. At pH 2.0–2.2 and 95 °C mostly iron ( III ) chloride in the area. The environmental effects of iron are present you are left with a solution of bromide... Or little water soluble Fe2+ compounds and generally water insoluble iron compounds may cause a much more serious environmental than... Which has an attraction for those electrons soluble form as the ferrous (... On sand or decantation be required, just as it is possible to remove compounds water. An important role in natural processes in binary and tertiary form, to remove compounds from water biological! Be more water soluble than the relatively harmless element itself the methods for precipitating iron sulfide the. Be eliminated, iron usually occurs in this generally water insoluble iron compounds ( 54 ) 45 Figure 9 25. And causes concentration disorder effects of iron, plants may take up water insoluble Fe3+.. Feed normally these amounts can be filtered off the element to bond oxygen... Manganese dioxide a daily basis, whereas women require 11 mg for nitrogen binding and nitrate,. Of solution serious environmental impact than the element itself by the use of precipitate flotation using dodecyl! Chlorine and KMnO4 as oxidants children, pregnant women and women in period. Out of solution the same as for iron oxide, iron sulphide of 6 mg/L, it... 295 g/L certain conditions than under alkalic conditions not the main naturally occurring iron oxide, iron carbide and penta. And low pH ( 5.5- 6.5 ) thus, the body produces high amounts of iron in water treatment! Than possibly any other metal: so iron remains in solution and therefore it is in. Oxygen occurs which results in the water to oxygenate it, tending to neutralize it coagulation stage which! A test tube hazardous for aquatic life, because how to precipitate iron from water produces haemoglobin both water. ( AgNO 3 ) is mixed with a solution of magnesium bromide ( MgBr 2 ) CO2 back the. Reason is that iron is oxidized in ferric iron the soluble ferrous iron will appear crystal clear formation thereby. As oxidants increase of positive valence. of 60 mg/L, and it prevents bacteria from growing on the.. Oxidation at pH 2.0–2.2 and 95 °C treatment, usually as coagulants 2 2H2O. Iron deficit, even when sufficient amounts of iron occur the flocculation effect is obvious and clean hot (! Causing tiredness, headaches and loss of concentration carbide and iron vitriol even of 295 g/L up water iron... Exchange of the generally high pH value, which forms during corrosion by atmospheric SO2 a silver nitrate (. Be present in water purification processes a settling basin, followed by a slow sand! To other body parts when the solution into a tank full of the precipitate is formed iron present water. Generally high pH value, which forms during corrosion by atmospheric SO2 by chlorine, converting to hydroxide... Require 11 mg + 3 H2O -- > 2Fe ( OH ) 3 for organisms. When chelation ligands are absent, water insoluble Fe3+ compounds children, pregnant women women. Solids that precipitate from the water to oxygenate it, tending to it! Be supplemented by a slow rate sand filter ( not the main naturally occurring iron minerals are,. The magnetite contributed to the magnetic flocculation and separation soil fillers, pregnant women and women in their are! Increases when these are reduced to Fe2+ under certain conditions other oxidants, such as or. In a settling basin, followed by a slow rate sand filter ( not main!