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Showing 1 to 18 of 18 for “"Ferric Hydroxide"”.
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Arsenic Stability In Fresh and Aged Amorphous Ferric Hydroxide Sludges Generated from Brine Treatment Processes
… arsenic brines by co-precipitation with iron oxyhydroxides is an established and effective remediation method for small quantities of highly concentrated liquid arsenic waste, such as brines derived from mine tailings, ion exchange resin regeneration, and reverse osmosis treatment of drinking …
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A Study of the Ferrous-Ferric System in Phosphoric Acid
… the oxidation-reduction potential of the ferrous-ferric system by using methods of procedure and apparatus that are easily reproducible under laboratory conditions. |In the media of various concentrations of orthophosphoric acid, the potential of the ferrous-ferric system is depressed far below …
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Leaching from High Capacity Arsenic-Bearing Solid Residuals under Landfill Conditions
… role in the mobilization of As from granular ferric hydroxide (GFH). Long term operation of GFH sorbent showed that Fe (III) was reduced to Fe(II) and As(V) was reduced to As(III) under anaerobic/reducing conditions. Under semi batch landfill simulation experiments, our results show that non …
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The effect of treatment process variations on the thickening and dewatering characteristics of water plant sludges
… pH and influent turbidity on aluminum and ferric hydroxide sludge macro-and micro-properties were investigated. To reduce the number of variables, sludges were produced under specific operating conditions in a 400 L/day continuous-flow pilot-plant. The effluent turbidity was monitored to …
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Application of phosphate and surfactant-modified zeolite for remediation/attenuation of trace elements in soil and coal fly ash
… (As(V)) and phosphate (Pi) adsorption on ferric hydroxide. Both oxyanions showed similar adsorptions during single-ion adsorption experiments; however, As(V) was preferentially adsorbed during competitive adsorption experiments. Similarly, more As(V) was adsorbed when it was loaded in …
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Aqueous Silica in the Environment: Effects on Iron Hydroxide Surface Chemistry and Implications for Natural and Engineered Systems
… fundamentals of silica sorption onto pre-formed ferric hydroxide at pH 5.0-9.5 and silica concentrations of 0-200 mg/L as SiO₂. Over the entire pH range studied, sorption densities exceeding monolayer sorption were observed at silica levels typical of natural waters. Under some circumstances, …
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The flotation of pyrite using xanthate collecters
… possibly due to the formation of hydrophilic ferric hydroxide. The addition of a xanthate collector improved the flotation properties of pyrite at all pHs. In acidic solutions the main effect observed was on the rate of pyrite recovery and on the grade of the concentrates. In alkaline …
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Understanding and Predicting Water Quality Impacts on Coagulation
… model. NOM is capable of interfering with ferric iron hydrolysis and influencing the size, morphology, and identity of precipitates. Conversely, calcium is known to increase the size and aggregation of Fe3+ precipitates and increase surface potential, leading to more effective coagulation …
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Geochemical Flow Modeling
… model was used to study both acid leaching using ferric sulfate solutions and alkaline leaching using carbonate solutions. For acid leaching. simulations revealed that the pyrite dissolution kinetics and potential precipitation of ferric hydroxide determine the leach solution selection. For …
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Phytate Extraction and Stimulation of Phytase by Zn & Mg in Seeds
… After phytic acid was extracted by hot HCl, ferric phytate was precipitated by adding an excess amount of ferric chloride. The iron of ferric phytate was converted to ferric hydroxide with NaOH and the amount of iron in each sample was spectrophotometrically determined.</p> <p>The results in …
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The Effect of Seed Sprouting Time and Light on Phytic Acid Concentration
… 1) phytic acid was extracted by hot HC1, 2) ferric phytate was precipitated by adding an excess of ferric chloride to the extraction, 3) ferric phytate was converted to ferric hydroxide with NaOH, and 4) the amount of iron in the samples was determined colorimetrically using o-phenanthroline …
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Treatment of acid mine drainage with Weirton steel slags
… diffusion of hydroxyl ions through the armored ferric hydroxide layer, which is produced by the neutralization. However the reaction with the limestone may be controlled by surface reaction with the acid. Thus, the neutralization with Weirton slag is less vulnerable to armoring than the …
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Evaluation of the KanchanTM Arsenic Filter under various water quality conditions of the Nawalparasi District, Nepal
… is removed via absorption onto the surface of ferric hydroxide, or rust, through the integration of locally available iron nails into a BioSand Filter setup. Since 2002, the KAF filter has been successfully disseminated in approximately 24,000 Nepali households. However, recent studies have …
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The Influence of Water Quality on Arsenic Sorption and Treatment Process Performance
… improved arsenic sorption to amorphous iron hydroxide in the presence of silica over short reaction times, but had no long-term advantage. This result could have considerable applications for treatment in that it suggests water quality controls the required reaction times. Additionally, batch …
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Mn(II) oxidation by HOCl in the presence of iron oxides: a catalyzing effect
… is fairly well understood; however, the role of ferric hydroxide/oxides (Fe(OH)₃<sub>(s)</sub>) in catalyzing the oxidation of Mn(II) by oxidants such as free chlorine (HOCI) is one specific aspect of manganese removal via oxidation that requires further investigation. Data collected in this …
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Integrative Bioassessment of Acid Mine Drainage Impacts on the Upper Powell River Watershed, Southwestern Virginia
… in close proximity to AMD discharges; 3) solid ferric hydroxide can cause acute toxicity to standard test organisms in the absence of dissolved iron; 4) Asian clams (Corbicula fluminea) can be used to detect both acutely toxic AMD inputs and nutrient loading in low order streams, and clam …
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Effect of Solution Chemistry on Schwertmannite Formation
… environment. We are using a poorly crystalline ferric hydroxysulfate nanomineral, schwertmannite, as a model system to understand the effect of formation conditions, specifically solution chemistry, on its physico-chemical characteristics. Previous studies indicate schwertmannite has highly …
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Examination of Silica Removal with Solids Recycle for Reverse Osmosis Pretreatment
… is operated at a pH of 10 or above. Magnesium hydroxide precipitates in this higher pH range thereby removing silica via a co-precipitation or adsorption mechanism. This project explored the relationship between magnesium concentration, pH, and silica removal in two phases. Phase 1 included 21 …