Adsorption Of Iron Research Articles

Role of Quercetin on iron homeostasis

Iron is crucial in processes such as oxygen binding in haemoglobin, electron transport in mitochondria, cell proliferation and differentiation, etc. Insufficient iron regulation can lead to either accumulation of iron that enhances oxidative stress or iron deficiency leading to altered cell growth and metabolism. As there is no regulated physiological mechanism for excretion of iron, iron homeostasis is maintained primarily by regulating iron absorption. Dietary iron content and other dietary constituents can have a major impact on iron homeostasis. Flavonoids are a group of compounds found in the diet either naturally or added as food additives. Therefore interaction of these compounds with iron is of interest. Quercetin, one of the most abundant flavonols in the diet, is an effective iron chelator and also acts as an antioxidant by modulating expression of antioxidant enzymes. Both of these properties of quercetin therefore can have an effect on iron absorption. The aim of this work was to elucidate the effect of quercetin administered by gavage or intraperitionally (IP) on iron uptake. Sprague Dawley male rats, fed on an iron deficient or iron replete diet for two weeks, were used as the animal model. Gene expression of selected intestinal proteins (DMT1, FPN, Dcytb, GLUT1 and SGLT1) was quantitated by Real-time PCR. Intestinal iron absorption was measured in another group of animals using the in situ loop method and radioactive iron. Additionally, levels of iron and transferrin saturation in serum, and nonheme iron in duodenum, liver and spleen, were determined. Results were obtained during 13 different treatments on animal models. Study showed that quercetin affects iron homeostasis by changing expression of proteins involved in iron absorption in greater amount when administrated orally than IP. Furthermore, after longer oral treatment with quercetin, animals became iron deficient as both liver and spleen iron levels decreased significantly, 1.2 and 1.1 fold, respectively. These results confirmed negative effects of polyphenols on iron adsorption when consumed in a diet for a longer time. Additionally, when administrated orally, quercetin significantly upregulated SGLT1 transporter, namely 1.8 and 1.6 fold, 18 hours and 5 hours before being sacrificed. These results indicate that quercetin is probably transported by SGLT1 in the duodenum. Moreover, in uptake experiments where quercetin was introduced into the duodenum together with radioactive iron, there was a significant difference in levels of radioactive iron accumulated by duodenal mucosa (increase 2.7 fold) or transferred to serum (decrease 7.3 fold), compared to controls. The most probable explanation is that quercetin chelates iron, and that the complex is transported into enterocytes, but is not further transported into circulation. However, other uptake experiments showed no change in concentration of absorbed iron. Bearing in mind our results and the fact that there was no change in concentration of absorbed iron in the mucosa and circulation during uptake studies, further experiments are needed in order to get a more complete picture of how quercetin affects iron absorption.

Novel Method To Reduce Fishy Aftertaste in Wine and Seafood Pairing Using Alcohol-Treated Yeast Cells

"Fishy aftertaste" is sometimes perceived in wine consumed with seafood. Iron in wine has been reported to be a key compound that produces fishy aftertaste. However, cost-effective methods to remove iron from wine have not been developed. Here, we describe a cost-effective and safe iron adsorbent consisting of alcohol-treated yeast (ATY) cells based on the observation that nonviable cells adsorbed iron after completion of fermentation. Treatment of cells with more than 40% (v/v) ethanol killed them without compromising their ability to adsorb iron. Drying the ATY cells did not reduce iron adsorption. Use of ATY cells together with phytic acid had a synergistic effect on iron removal. We term this means of removing iron the "ATY-PA" method. Sensory analysis indicated that fishy aftertaste in wine-seafood pairings was not perceived if the wine had been pretreated with both ATY cells and phytic acid.

Iron removal using adsorptive filtration treatment for low iron concentration water from urban industrial region

Iron in urban runoff water from urban industrial regions is undesirable because of aesthetic and operational reasons. Generally iron is removed by chemical treatment processes. However, these systems have a limitation for water recycled as drinking water resources (∠0.3 mg/L). Conventionally, low iron concentration (0.3 mg/L–6 mg/L) in runoff is treated by the process of aeration followed by filtration in water treatment. The shortcomings of this process include short filter runs due to fouling by large volumes of sludge production and elevated headloss. Iron (II) is present in surface runoff in the urban industrial region and roadway, and can be removed by the adsorptive filtration or the conventional floc filtration process. The adsorptive filtration process has several potential advantages such as longer run, shorter ripening time, low sludge production and cost saving. In this study, the adsorptive filtration process shows better performance than the floc filtration. The use of the adsorptive filtration process is a feasible strategy to reduce the filter ripening time and sludge production with high iron (II) adsorption capacity. Also, this method can apply for treatment of discharging surface runoff and can be used as an alternative water resource through a decentralized system or best management practices (BMPs).

Use of argillaceous materials containing sediments of dam in the retention of heavy metals

The interaction of heavy metals like Fe (II), and Cu (II) ions from aqueous solutions is studied using sediments of dam activated by impregnation with ammonium chloride (VNE) and thermally activated at 300°C (V300). This study of retention of two metals allowed us to notice shows that: the rate of retention of metals using "V300" (thermal activation) is better then using "VNE". The retention of metals is governed by the model of adsorption of Langmuir for iron and of Freundlich for copper. Because of high surface area per unit area, activated mud is the most effective adsorbent and exhibits high capacity of adsorption of iron and copper. Mud of dam activated by impregnation with ammonium chloride (VNE) and thermally activated at 300°C has a considerable potential for the removal of heavy metal cationic species from aqueous solution

Homogeneous, heterogeneous and biological oxidation of iron(II) in rapid sand filtration

Research Article| February 01 2012 Homogeneous, heterogeneous and biological oxidation of iron(II) in rapid sand filtration C. G. E. M. van Beek; C. G. E. M. van Beek 1KWR Watercycle Research Institute, PO Box 1072, 3430 BB Nieuwegein, The Netherlands E-mail: Kees.van.Beek@kwrwater.nl Search for other works by this author on: This Site PubMed Google Scholar T. Hiemstra; T. Hiemstra 2Wageningen University, Department of Soil Quality, PO Box 47, 6700 AA Wageningen, The Netherlands Search for other works by this author on: This Site PubMed Google Scholar B. Hofs; B. Hofs 1KWR Watercycle Research Institute, PO Box 1072, 3430 BB Nieuwegein, The Netherlands Search for other works by this author on: This Site PubMed Google Scholar M. M. Nederlof; M. M. Nederlof 1KWR Watercycle Research Institute, PO Box 1072, 3430 BB Nieuwegein, The Netherlands Search for other works by this author on: This Site PubMed Google Scholar J. A. M. van Paassen; J. A. M. van Paassen 3Water utility Vitens, PO Box 1090, 8200 BB Lelystad, The Netherlands Search for other works by this author on: This Site PubMed Google Scholar G. K. Reijnen G. K. Reijnen 4Water utility WML, PO Box 1060, 6201 BB Maastricht, The Netherlands Search for other works by this author on: This Site PubMed Google Scholar Journal of Water Supply: Research and Technology-Aqua (2012) 61 (1): 1–13. https://doi.org/10.2166/aqua.2012.033 Article history Received: May 03 2011 Accepted: November 15 2011 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Cite Icon Cite Permissions Search Site Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsThis Journal Search Advanced Search Citation C. G. E. M. van Beek, T. Hiemstra, B. Hofs, M. M. Nederlof, J. A. M. van Paassen, G. K. Reijnen; Homogeneous, heterogeneous and biological oxidation of iron(II) in rapid sand filtration. Journal of Water Supply: Research and Technology-Aqua 1 February 2012; 61 (1): 1–13. doi: https://doi.org/10.2166/aqua.2012.033 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex Homogeneous, heterogeneous and biological oxidation may precipitate iron(II) as iron(III) hydroxides. In this paper we evaluate the conditions under which each of these processes is dominant in rapid sand filtration (RSF). It is demonstrated that in the presence of iron(III) hydroxide precipitates homogeneous oxidation is negligible compared with heterogeneous oxidation. As soon as iron oxidizing bacteria (IOB) are present, biological oxidation may contribute substantially, in particular under conditions of slight acidity and low oxygen concentration. As the oxidation step is preceded by an adsorption/uptake step, the competition between heterogeneous and biological oxidation is not determined by the oxidation rate, but by the adsorption or uptake rate. Extracellular polymeric substance (EPS), excreted by all kinds of bacteria, may serve as an initial adsorbent for dissolved iron(II) and iron(III) hydroxides. Because adsorption and oxidation of iron (II) either on biofilms (or EPS) or on mineral surfaces, are chemical processes, ‘EPS iron oxidation’ is not considered as a biological process. The so-called ‘biological iron oxidation’ actually refers to a treatment method characterized by high filtration rates and limited oxygen supply, where iron(II) is removed mainly by heterogeneous oxidation. The contribution of oxidation of iron(II) by IOB in this method is variable and may even be absent. drinking water, groundwater, hydrous ferric oxides, iron(II) oxidation, iron removal, rapid sand filtration This content is only available as a PDF. © IWA Publishing 2012 You do not currently have access to this content.

Evaluation of chitosan tripolyphosphate gel beads as bioadsorbents for iron in aqueous solution and in human blood in vitro

AbstractNonimprinted and Fe3+ imprinted chitosan tripolyphosphate gel beads were prepared via physical gel formation. A method based on in situ crosslinking using ethylene glycol diglycidyl ether was developed to imprint the chitosan tripolyphosphate gels with Fe3+ ion without deteriorating the gel beads. The beads were characterized by FTIR, SEM, XRD, and DSC with respect to the chemical structure, surface morphology, crystallinity, and thermal behavior. Swelling kinetics and Fe3+ ion adsorption behavior from aqueous solution were studied. The Fe3+ imprinted and in situ crosslinked beads proved to be durable and effective adsorbents for Fe3+ in solution. The bead prepared by in situ crosslinking and in the presence of 10 mM template ion had an equilibrium iron adsorption capacity of 53.9 mg/g after 3‐hour contact with 5 mM Fe3+ solution. The pros and cons of the beads as biomedical iron adsorbents were tested by evaluating their serum iron removal capacities from human blood. The preliminary tests carried out showed that Fe3+ imprinted beads were more effective in decreasing serum iron in human blood when compared to the nonimprinted beads. The decrease in serum iron level accompanied a parallel decrease in the hemoglobin level. The calcium level was also affected upon contact with the beads. The Fe3+ imprinted beads were less effective than the nonimprinted ones in decreasing the calcium level indicating selectivity towards iron containing species. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Synergistic effects of TiO2 photocatalysis in combination with Fenton-like reactions on oxidation of organic compounds at circumneutral pH

The integration of two different AOPs often offers synergistic reaction routes for the production of OH. In this study, synergistic production of OH was observed in the combined system of TiO2 photocatalysis and the Fenton-like reaction, causing a drastic enhancement in the oxidation of organic compounds at circumneutral pH values. The photolytic experiments using organic substrates (i.e., phenol, benzoic acid, and methanol) and valence band hole and OH scavengers (i.e., formate and tert-butyl alcohol) show that the synergistic effects result from dual roles of iron as an electron acceptor to facilitate charge separation in TiO2 photocatalyst and as a Fenton reagent to catalyze conversion of H2O2 into OH. A noteworthy observation is that the adsorption of iron onto the photoexcited TiO2 surface possibly modifies electron transfer properties of iron toward H2O2 at neutral pH to convert the resultant reactive oxidant from Fe(IV) into a stronger form, likely OH.

Adsorption of heavy metal from landfill leachate by wasted biosolids

The adsorption capacity of wasted solids that contained dead fungal biomass (Phanerochaete chrysosporium) was studied to remove cadmium, copper, zinc and iron from synthetic water and leachate. The biomass was produced due to the experiments conducted for bioconversion of wastewater for lignin peroxydase production in the laboratory. In the screening experiments, the maximum cadmium (Cd) adsorption from synthetic water was 28.81% at 18 h. Meanwhile, adsorption of copper (Cu), zinc (Zn) and iron (Fe) reached maximum condition after 5 h with 41.29, 58.94 and 52.03% removal efficiency, respectively. However, the concentration of Cd, Cu and Zn was not detected in the leachate but Fe was found to be in high concentration (184 mg/L) in raw leachate collected from a municipal landfill site. Therefore, the effects of biomass dosage, contact time, pH and agitation speed were observed for optimal adsorption of iron from leachate. Optimum removal of iron from leachate was 45.56% in every 1 L of leachate after 1/50 dilutions. The optimized biomass dosage, contact time, pH and agitation speed were 750 mg/L, 4 h, pH 5, and 150 rpm, respectively. The results of this study indicated that the biomass generated from the laboratory experiments could be used, before discarding, to remove iron from leachate which is one of the main problems at the landfill sites.

Potential use of bagasse and modified bagasse for removing of iron and phenol from water

Abstract The potential of bagasse, chemically modified and thermally charring bagasse for iron and phenol adsorption were studied. Graft copolymerization of acrylonitrile onto cellulosic material derived from bagasse in heterogeneous medium can be initiated effectively with Fe+2/H2O2. The effect of initiator and monomer concentration as well as grafting time and temperature were investigated. The grafted products were evaluated with FTIR and their iron and phenol adsorption from water. The results obtained for both phenol and iron adsorptions were dependent on the nature of adsorbent, which had been changed according to the type of modification carried out on bagasse adsorbent. The extent of iron adsorption is less than that of phenol for all adsorbents and for certain adsorbent (phenol or iron) the ranking of adsorbent efficiency is charred > grafted > bleached > unbleached > raw material. The results showed that the equilibrium data for iron and phenol-sorbent systems fitted the Freundlich model best within the concentration range studied.

Mechanism of adsorption of ferric iron by extracellular polymeric substances (EPS) from a bacterium Acidiphilium sp.

The aim of this study was to assess the sorption of Fe(III) by extracellular polymeric substances (EPS) of the Acidiphilium 3.2Sup(5) bacterium, which has promising properties for use in microbial fuel cells (MFC). The EPS of A. 3.2Sup(5) was extracted using EDTA. The sorption isotherms were determined using aliquots of purified EPS. The exosubstances loaded with metal were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction spectroscopy (XRD) and Fourier transform infrared spectroscopy (FTIR). The sorption uptake approaches to 536.1 +/- 26.6 mg Fe(III) (g EPS)(-1) at an initial ferric concentration of 2.0 g l(-1). The sorption of Fe(III) by EPS can be fitted to the Freundlich model. The sorption process produces hydrated iron (III) oxalate [Fe(OH)(C2O4) x 2H2O] by a reversible reaction (log K = 1.06 +/- 0.16), indicating that a shift in the sorption of the cation can be easily achieved. Know the magnitude and form of iron sorption by EPS in MFC can foresee the potential impact on the metabolism of iron-reducing and iron-oxidazing bacteria and, therefore, on the feasibility of the system.

Effects of alternating current (AC) and direct current (DC) in electrocoagulation process for the removal of iron from water

AbstractIn practice, direct current (DC) is used in an electrocoagulation processes. In this case, an impermeable oxide layer may form on the cathode as well as corrosion formation on the anode due to oxidation. This prevents the effective current transfer between the anode and cathode, so the efficiency of electrocoagulation processes declines. These disadvantages of DC have been diminished by adopting alternating current (AC) in electrocoagulation processes. The main objective of this study is to investigate the effects of AC and DC on the removal of iron from water using zinc as anode and cathode. The results showed that the optimum removal efficiency of 99.6% and 99.1% with the energy consumption of 0.625 and 0.991 kWh kL−1 was achieved at a current density of 0.06 A dm−2, at pH of 7.0 using AC and DC, respectively. For both AC and DC, the adsorption of iron was preferably fitting Langmuir adsorption isotherm, the adsorption process follows second order kinetics and the temperature studies showed that adsorption was exothermic and spontaneous in nature. © 2011 Canadian Society for Chemical Engineering

Influence of impregnation ratio on coffee ground activated carbon as landfill leachate adsorbent for removal of total iron and orthophosphate

Coffee grounds waste was used to prepare activated carbon with particle size between 1.18 and 2 mm by chemical activation with sulphuric acid. The influence of impregnation ratio on physical properties of activated carbon and removal efficiency of total iron and orthophosphate (PO 4–P) was studied. Impregnation ratio of 0.5 was found optimum for preparing activated carbon with high pore surface area (224.7 m 2/g) and micropore volume (0.07986 cm 3/g). Batch experiments were conducted to study the effects of contact time, pH, particle size and adsorbent dosage. Impregnation ratios of 2.5 and 0.5 were found to be optimum for the adsorption of total iron and PO 4–P, respectively at doses of 10 g and pH 8.1. pH 13 was optimum for iron removal while pH < 5 and > 11 was optimum for PO 4–P removal. The adsorption capacity increased with increasing adsorbent dosage for total iron. However, this trend was exceptional for PO 4–P with fluctuating adsorption capacity. The smaller particle size yielded larger adsorption capacity.

Adsorption of Iron (III), Lead (II) and Cadmium (II) Ions by Unmodified Raphia Palm (Raphia hookeri) Fruit Endocarp

Adsorption of Iron (III), Lead (II) and Cadmium (II) Ions by Unmodified Raphia Palm (Raphia hookeri) Fruit Endocarp

Structural stability and electronic structure of iron adsorption on the GaN(0 0 0 1) surface

In this work, we have investigated by means of first-principles spin-polarized calculations, the electronic and magnetic properties of iron (Fe) adsorption and diffusion on the GaN(0 0 0 1) surface using density functional theory (DFT) within a plane-wave pseudopotential scheme. In the surface adsorption study, results show that the most stable positions of a Fe adatom on GaN(0 0 0 1) surface are the H3 sites and T4 sites, for low and high Fe coverage respectively. We found that the Fe–H3 2 × 2 surface reconstruction exhibits a half-metallic behavior with a spin band gap and stable ferromagnetism ordering, which is a desirable property for high-efficiency magnetoelectronic devices. In addition, confirming previous experimental results, we found that the iron monolayers present a ferromagnetic order and a large thermal stability. This is interesting from a theoretical point of view and for its technological applications.

Preconcentration of metal ions on aluminum oxide modified with tiron

It is found that iron(III), titanium(IV), vanadium(V), copper(II), lead(II), and zinc(II) ions are adsorbed on aluminum oxide modified with Tiron. The adsorption of iron(III) is accompanied by the violet coloration of the adsorbent (560 nm), which indicates the formation of a 1: 2 complex on the adsorbent surface; copper forms a 1: 1 yellowish green complex (430 nm). The group preconcentration of metal ions on this adsorbent in a dynamic mode is possible; the preconcentration rate is 2.5 × 103. The method for the determination of metal ions is proposed based on the adsorption recovery of the elements followed by the direct determination by X-ray fluorescence spectroscopy on the adsorbent surface.

10.2478/s11814-009-0176-9

The present study provides an electrocoagulation process for the removal of iron from drinking water with aluminum alloy as the anode and stainless steel as the cathode. The studies were carried out as a function of pH, temperature and current density. The adsorption capacity was evaluated with both the Langmuir and the Freundlich isotherm models. The results showed that the maximum removal efficiency of 98.8% was achieved at a current density of 0.06 A dm−2, at a pH of 6.5. The adsorption of iron preferably fitting the Langmuir adsorption isotherm suggests monolayer coverage of adsorbed molecules. The adsorption process follows second-order kinetics. Temperature studies showed that adsorption was endothermic and spontaneous in nature.

Adsorption of iron on crude olive stones

The ability of crude olive stones, a residue of the olive-oil industry, for the adsorption of iron present in the industrial wastewaters was studied. Olive stones were used directly and characterized by mercuric porosimetry. The equilibrium adsorption capacity was higher when the particles size (from <1 to 4.8 mm) decreased. The percentage of iron adsorption increased from 30 to 70% when the initial concentration of biomass increased from 25 to 125 g dm −3. The optimum concentration of olive stones was fixed at 37.5 g dm −3. The adsorption of iron was determined as a function of their initial concentration and multiplayer formed at high iron concentration.

Production, characterization and application of activated carbon from brewer’s spent grain lignin

Different types of activated carbon were prepared by chemical activation of brewer’s spent grain (BSG) lignin using H 3PO 4 at various acid/lignin ratios (1, 2, or 3 g/g) and carbonization temperatures (300, 450, or 600 °C), according to a 2 2 full-factorial design. The resulting materials were characterized with regard to their surface area, pore volume, and pore size distribution, and used for detoxification of BSG hemicellulosic hydrolysate (a mixture of sugars, phenolic compounds, metallic ions, among other compounds). BSG carbons presented BET surface areas between 33 and 692 m 2/g, and micro- and mesopores with volumes between 0.058 and 0.453 cm 3/g. The carbons showed high capacity for adsorption of metallic ions, mainly nickel, iron, chromium, and silicon. The concentration of phenolic compounds and color were also reduced by these sorbents. These results suggest that activated carbons with characteristics similar to those commercially found and high adsorption capacity can be produced from BSG lignin.

Mössbauer and EXAFS spectroscopy investigation of iron and arsenic adsorption to lettuce leaves

The accumulation of iron and arsenic from aqueous solution by lettuce leaves biomass was investigated using Mossbauer and EXAFS spectroscopic techniques. Mossbauer spectroscopy results show that iron is oxidized during sorption while EXAFS results indicate that iron is coordinated by approximately 6 oxygen and 2 carbon atoms while arsenic is coordinated by approximately 4 oxygen atoms with iron as a second neighbor.

Self-assembled hemocompatible coating on poly (vinyl chloride) surface

A stable hemocompatible coating was fabricated by consecutive alternating adsorption of iron (III) and two kinds of polysaccharides, heparin (Hep) and dextran sulfate (DS), onto poly (vinyl chloride) (PVC) surfaces via electrostatic interaction. The fluctuation of contact angles with the alternative deposition of iron (III) and polysaccharides verified the progressive buildup of the mulitilayer coating onto the PVC surface. Atomic force microscopy (AFM) analysis revealed that the PVC surfaces were completely masked by iron–polysaccharides multilayer coatings. The activated partial thromboplastin time (APTT) assay showed that both Hep/Fe 3+/Hep and DS/Fe 3+/Hep coated PVC were less thrombogenic than the uncoated one. Chromogenic assay for heparin activity proved definitively that the inhibition of locally produced thrombin was ascribed to the thromboresistance of the surface-bound heparin. Compared with the unmodified PVC surfaces, iron–polysaccharide multilayer coating presented a drastically reduced adhesion in vitro of platelets, polymorphonuclear neutrophil leukocytes (PMN) and peripheral blood mononuclear cells (PBMC). Interestingly, the DS/Fe 3+/Hep coating was found to exhibit higher hydrophilicity and stability, hence lower non-specific protein adsorption in comparison with Hep/Fe 3+/Hep coating due to the incorporation of dextran sulfate into the multilayer coating.