Silica Sand Etching Behavior During a Primary Step …
The most influencing parameters on silica leaching are leaching time and particles sand size. Our work consists of the study of …
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Iron Removal Process for High-Purity Silica Sands …
In this article, a leaching study, carried out on a quartz sample to obtain high-purity silica sands, has been presented. A leaching process by using oxalic acid …
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Recovery of Silicon Dioxide from Waste Foundry Sand and
Abstract This study was conducted to recover silica (desilication) as a valuable metalloid from waste foundry sand (WFS) by a leaching process and to find application for desilicated foundry sand (DFS). The leaching time applied was 5 h; 3 M of potassium hydroxide (KOH) was used as a leaching reagent. The agitation speed of 200 …
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Technical noteInnovative technology for the …
Under optimal leaching conditions, the SiO 2 purity of silica sand increased to 97.42%. Following a three-stage acid leaching process with 4 mol/LHCl +2 mol/LH 2 C 2 O 4, the removal efficiency of Al, Ca, Fe, and Mg exceeded 97% for all cases, and the SiO 2 …
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Optimization of Quartz Sand Leaching Process Using …
The sand from the Djelfa deposit has a high concentration but not enough to be used as raw material for pyrometallurgy (97%) of SiO 2. Therefore, the quartz was treated using acid leaching process to increase the silica concentration up to 98.5%. Otherwise, we employ Design of Experiments Method Software (DOE) as numerical …
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Iron Removal Process for High-Purity Silica Sands …
In this article, a leaching study, carried out on a quartz sample to obtain high-purity silica sands, has been presented. A leaching process by using oxalic acid to remove low iron content from the ore under study and to obtain a material suitable for fiber optic production has been evaluated. A characterization study has been carried out to …
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Progress, Challenges, and Perspectives of Bioleaching for
Biological leaching methods for the treatment of electronic waste can be divided into three types according to the type of biomass exposure to the waste: one-step, two-step, and spent-medium [].In the study of biological leaching of heavy metals from tailings, the operation steps are generally as follows (Figure 2): first, the tailing samples …
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Silica Sand Etching Behavior During a Primary …
Thus, we have studied etching effect on particle granulometric size during a primary step of leaching process on Algerian silica sand with HF at 20% during 2, 4 and 6 hours. Therefore, a new ...
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Evaluating life cycle environmental impacts of coal fly ash …
The leaching data was collected by the authors based on US EPA leaching methods (US EPA Method 1315, 2017; US EPA, 2012; US EPA, 2017). Therefore, a combination of existing GaBi modules (landfill process, truck for material transport, compaction equipment, and diesel supply) and original modules (leaching process and …
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Optimization of Quartz Sand Leaching Process Using …
Optimization of Quartz Sand Leaching Process Using Design Experiments Method (DOE) | Request PDF. Authors: Kefaifi Aissa. Centre de Recherche en Technologie des Semi-conducteurs pour...
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Quartz Sand Iron Removal Methods
Quartz sand is a non-metallic mineral with a wide range of applications in traditional fields such as glass products, building materials, waterproof and anti-corrosion materials, and high-tech ...
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Leaching | Soil Chemistry, Nutrient Loss & Pollution
Leaching, in geology, loss of soluble substances and colloids from the top layer of soil by percolating precipitation. The materials lost are carried downward (eluviated) and are generally redeposited (illuviated) in a lower layer. This transport results in a porous and open top layer and a dense,
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Process development to recover rare earth metals from monazite …
A roast–leach process has been reported for the extraction of rare earth from complex monazite concentrates using sulfuric acid and other leaching agents at the Pea Ridge iron mine in Sullivan (Franken, 1995). In this process, the RE phosphate of the ore is converted to its oxide, which eliminated hazardous processing steps currently in practice.
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Progress in bioleaching: fundamentals and mechanisms of
In general, leaching bacteria seem to grow attached to the surfaces of mineral sulfides. In case of not limiting surface space, some microorganisms with good attachment capabilities to mineral surfaces exhibit attachment of up to 80–90% of the planktonic cells within less than one day (Gehrke et al. 1998; Harneit et al. 2006).It is quite obvious that …
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Effect of quartz crystal structure transformations on
The removal of iron impurities is one of the technical difficulties in the preparation process of high-purity quartz sand. In this work, the effect of the transformation of the crystal structure on the removal of iron impurities in quartz sand was investigated. After respectively roasting at 600 °C, 900 °C, and 1200 °C for 4 h, the crystal ...
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Enhancing the Performance of Bottom Ash Using Acid Leaching …
This paper reports a research on the leaching process of bottom ash and the effect on the physical characteristics and compressive strength of the mortar containing bottom ash as sand replacement. The bottom ash was subjected to leaching with Hydrochloric, Citric, Nitric, Sulfuric and Hydrofluoric acids.
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Optimization of Quartz Sand Leaching Process Using …
In this context, the optimal grain sizes of sand and the optimal acid concentration are respectively, 276.9 µm and 21.15%, for 6 hours leaching time. The …
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Hydrometallurgical Recovery of Gold from Mining Wastes
2.1 Cyanide leaching. Cyanide is a cheap but highly toxic reagent that is very effective in leaching gold from low-grade minerals and mining wastes. Therefore, cyanidation is the most widely used method for the extraction of gold from mining wastes.
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Recovery of Zinc and Iron from Steel Mill Dust—An Overview …
The leaching process using concentrated acid as a leaching agent required the equipment to have good acid corrosion resistance. ... The raw materials of this process are converter dust, quartz sand and coarse iron ore powder. These raw materials are first mixed evenly, then agglomerated in the sintering process and finally smelted in the ...
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Innovative technology for the production of high-purity sand …
Under optimal leaching conditions, the SiO 2 purity of silica sand increased to 97.42%. Following a three-stage acid leaching process with 4 mol/LHCl +2 mol/LH 2 C 2 O 4, the removal efficiency of Al, Ca, Fe, and Mg exceeded 97% for all cases, and the SiO 2 purity in high-purity silica reached 99.93%. Thus, this study proposes a new strategy ...
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Effects of Rice Husk Biochar on Nitrogen Leaching from …
The application of biochar can affect soil properties and retention of fertilizer nitrogen, but its effects and mechanism on the retention capacity of different forms of nitrogen in soils are still uncertain. In this study, an indoor soil column leaching experiment was conducted using vegetable soil samples with 3% rice husk biochar by mass prepared …
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Developing circular concrete: Acid treatment of waste …
The aim of this research was to optimize acid leaching of waste concrete fines using the process shown in Fig. 1.The optimal conditions for acetic acid leaching of waste concrete fines to produce clean extracted sand are identified and the pozzolanic activity of the dried silica rich residue is assessed.
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Leaching Gold from Finely Crushed Ore (Sand Leach)
The leaching cock is better kept closed until the whole charge is saturated and the solution stands permanently above the level of the sand. It may then be opened and regulated to any desired rate of flow. When the cyanide process was first introduced a great point was made of letting the solution remain in contact for many hours before drawing ...
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Recovery of Silicon Dioxide from Waste Foundry …
The leaching time applied was 5 h; 3 M of potassium hydroxide (KOH) was used as a leaching reagent. The agitation speed of 200 rpm and the liquid/solid ratio of …
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Kinetics of iron removal from quartz under ultrasound-assisted leaching
where x is the iron removal rate, θ is the amount of iron in the leached solid sample and α is the amount of iron in ore sample.. 3 Results and discussion 3.1 Kinetic analysis of iron leaching process. The shrinking core model is the most commonly used liquid–solid phase non-catalytic reaction model [].In the interface reaction model without solid products, the …
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(PDF) Process development to recover rare earth metals …
Different authors studied the direct leaching of monazite sand. ... leaching process where. mineral was digested by 98% H. 2. SO. 4. and dissolved in cold water (1:20) then precipitated with.
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Monazite Sand
A modified flowchart of the alkaline digestion, leaching, and extraction of uranium from Egyptian monazite is presented in Fig. 28 (El-Nadi et al., 2005). Similarly, thorium was recovered from Egyptian monazite sand after alkaline treatment and leaching with alkaline carbonate solution (Ali et al., 2007). This process was further studied to ...
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An integrated and sustainable hydrometallurgical process …
In this study, an integrated and sustainable hydrometallurgical process was developed to recover copper, zinc, and lead from roasted sand of WPCB-SA, and to enrich gold and silver; 99.85% of copper and 99.47% of zinc in the roasted sand were separated efficiently during water leaching, and the loss rate of silver was 2.1% at an NaCl ...
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(PDF) The Modeling and Optimization of Iron Removal from Silica Sand
The following were found to be the best conditions for the leaching process variables: 83.2051 leaching temperature, 0.0827mm particle size, 3.6179mol/dm3 acid concentration; 0.0287g/cm3 kaolin to ...
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(PDF) Dissolution of quartz sand in sodium hydroxide …
The experimental results show that the optimum condition of the leaching process occurs at a reaction time of 5 hours with a sulfuric acid concentration of 10 N. The silica levels increase from 93 ...
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