zinc silicate dissolution in sodium hydroxide

zinc silicate dissolution in sodium hydroxide

The Depolymerization of Silica in Sodium Hydroxide ...

The alkaline leaching kinetics of a zinc silicate ore assaying 34.1% Zn, 11.1% Fe and 22.9% SiO 2 is studied in sodium hydroxide solutions. Speciation diagrams indicate zinc dissolution as [Zn(OH) 4] 2− and SEM analysis showed a progressive reduction in particle size during leaching which supports the shrinking particle model. The process is chemically controlled with an activation energy of ...

How to Dissolve Silicate | Sciencing

This allows the dissolution of Ca(OH) 2 (portandite) and increases the concentration of Ca 2+ ions into the cement pore water. Calcium ions then react with the soluble sodium silicate gel to convert it into solid calcium silicate hydrates (C-S-H). The C-S-H forms a continuous poorly permeable coating at the external surface of the aggregate.

Mechanochemical leaching of refractory zinc silicate ...

Abstract. Effect of calcium on the solubility of zinc oxide in the sodium hydroxide solution was studied in this paper. Results showed that ZnO equilibrium concentration was different at different temperatures when CaO or Ca(OH) 2 was added to the saturated sodium zincate solution of Na 2 O-ZnO-H 2 O system. ZnO equilibrium concentrations had little change with Ca(OH) 2 added at 100°C.

redox

Crystalline zinc silicate, Zn2SiO4, and zinc ferrite, ZnFe2O4, were prepared and characterized. The solubilities of these phases were measured using flow-through apparatus from 50 to 350 °C in 100 °C intervals over a wide range of pH. Both solid phases dissolve incongruently, presumably to form ZnO(s) and Fe2O3(s) (or the corresponding hydroxide phases at low temperature), respectively.

zinc silicate leaching

Zinc reacts with hot and conc. sodium hydroxide to form sodium zincate with the liberation of hydrogen. Zn + 2NaOH → Na 2 ZnO 2 + H 2 Sodium zincate

Sodium Hydroxide

Silicon is second only to oxygen as the most abundant element in the crust. Silicon combines with other elements, such as calcium, iron, potassium and magnesium to form a wide range of silicate material. Natural acids form when rain combines with elements in the atmosphere. These acids dissolve …

Effect of Calcium on the Solubility of Zinc Oxide in the ...

The dissolution kinetics of lead and zinc was examined according to the shrinking core models and it was distinguished that the leaching process of lead and zinc in sodium hydroxide solution followed the kinetic law of the shrinking core model with the fluid film diffusion as the rate-controlling step.

How to Make Sodium Silicate From Sodium Hydroxide | Sciencing

ZnO−H2O system in the sodium hydroxide solution was revalued from 25 to 100 °C. The solubility of zinc oxide is different from the report by URAZOV et al while it is similar to that in the KOH solution. It is instructive to treat zinc oxide ores with sodium hydroxide. 2) The change tendency of the solubility of zinc

Leaching behaviour of zinc from a smithsonite ore in ...

The role of the dissolution of silicic acid powders in aluminosilicate synthesis mixtures in the crystallization of large mordenite crystals. Zeolites 1996, 16 (2-3), . DOI: 10.1016/(95). M. Dietzel, E. Usdowski. Depolymerization of soluble silicate in …

Effect of sodium silicate on the solubility of zinc oxide ...

@article{osti_, title = {Reaction of sodium hydroxide with silicate minerals}, author = {Thornton, S D}, abstractNote = {The reactions of individual silicate minerals with caustic solution were measured over a 1-week period. These silicate minerals included: two feldspars (microcline and albite), two micas (biotite and muscovite), and three clays (chlorite, Kaolinite and montmorillonite).

Silicon dioxide

Alum, zinc chloride and sodium silicate/diluted hydrochloric acid were found to have negligible dissolution-inhibiting effects for buffer solution with pH 5.95, and sodium silicate/zinc chloride ...

Investigation of the Anodic Dissolution of Zinc in Sodium ...

AutoClave for dissolving Sodium Silicate solid . · This can be done in an autoclave, either stationary or rotary. The pressure-dissolving is continued until the sodium silicate solutions has a specific from solid sodium silicate glass, said process comprising (a) dissolvingenough of said silicate .

Investigation of the Anodic Dissolution of Zinc in Sodium ...

Zinc oxide react with sodium hydroxide to produce zincate sodium and water. This reaction takes place at a temperature of °C. Find another reaction. Our channel. Thermodynamic properties of substances The solubility of the substances Periodic table of elements. Picture of reaction:

boiler for dissolving sodium silicate glass

To increase leaching rate of zinc, the effect of sodium silicate on the solubility of zinc oxide of the Na2O–ZnO–SiO2–H2O equilibrium system is studied by adding Na2SiO3 and ZnO to NaOH ...

156 Zinc Oxide and Hydroxide

Apr 23, 2017· leaching plant zinc ore separation efficient Sulfuric acid leaching of zinc silicate ore under pressure . The obtained results show that the acid leaching of zinc silicate ore under pressure was found to be more efficient compared to other zinc hydrometallurgical process in terms of decreased dissolution of silica and iron and increased zinc extraction.

The kinetics of zinc silicate leaching in sodium hydroxide ...

This study uses empirical experimental evidence and Material Studio simulations to explain the interaction of sodium hydroxide (NaOH) with quartz. Density functional theory (DFT) calculations were carried out using the Cambridge Serial Total Energy Package. In addition, quartz grains subjected to dissolution in NaOH were characterized using scanning electron microscopy.

Molecular simulation and microtextural characterization of ...

ZnO−H2O system in the sodium hydroxide solution was revalued from 25 to 100 °C. The solubility of zinc oxide is different from the report by URAZOV et al while it is similar to that in the KOH solution. It is instructive to treat zinc oxide ores with sodium hydroxide. 2) The change tendency of the solubility of zinc

Alkaline leaching of lead and zinc by sodium hydroxide ...

Zinc react with sodium hydroxide to produce zincate sodium and hydrogen. This reaction takes place at a temperature near 550°C. Find another reaction. Our channel. Thermodynamic properties of substances The solubility of the substances Periodic table of elements. Picture of reaction:

The kinetics of zinc silicate leaching in sodium hydroxide

Apr 23, 2017· leaching plant zinc ore separation efficient Sulfuric acid leaching of zinc silicate ore under pressure . The obtained results show that the acid leaching of zinc silicate ore under pressure was found to be more efficient compared to other zinc hydrometallurgical process in terms of decreased dissolution of silica and iron and increased zinc extraction.

Sodium hydroxide

Concentration of sodium hydroxide solution was maintained 10 M and sodium silicate to sodium hydroxide ratio was fixed as 2.5:1 by weight. ... The dissolution of aluminosilicates is initiated by ...

Alkaline leaching of lead and zinc by sodium hydroxide ...

Sodium hydroxide (Na OH), also known as lye or caustic soda, is a caustic metallic base. An alkali, caustic soda is widely used in many industries, mostly as a strong chemical base in the manufacture of pulp and paper, textiles, drinking water, and detergents. Worldwide production in 1998 was around 45 million tonnes. Sodium hydroxide is also the most common base used in chemical laboratories ...

Effect of sodium silicate on the solubility of zinc oxide ...

The alkaline leaching kinetics of a zinc silicate ore assaying 34.1% Zn, 11.1% Fe and 22.9% SiO2 is studied in sodium hydroxide solutions. Speciation diagrams indicate zinc dissolution as [Zn(OH)4 ...

Sodium aluminate

The alkaline leaching kinetics of a zinc silicate ore assaying 34.1% Zn, 11.1% Fe and 22.9% SiO2 is studied in sodium hydroxide solutions. Speciation diagrams indicate zinc dissolution as [Zn(OH)4 ...

Dissolution kinetics of smithsonite ore as an alternative ...

Investigation of the Anodic Dissolution of Zinc in Sodium ... [33–35], in sodium hydroxide in presence of sodium silicate and sodium tetraborate [13], in sodium hydroxide in presence of sulfur containing ions such as Na 2 SO 4, Na 2 SO 3, Na 2 S, Na 2 S 2 O 3 or NH 4 SCN

boiler for dissolving sodium silicate glass

The corrosion and electrochemical studies of zinc dissolution in sodium chloride solutions have been investigated in the literatures [14,17–19]. For pH >12, a passive layer composed of zinc hydroxide and/or zinc oxide is formed on the surface of the zinc sample [19]. In an aerated acidic NaCl solution, the

zinc silicate leaching

due to the formation of solid zinc hydroxide and solid zinc oxide phases, respectively. It was observed that increasing leaching time from 1800 to 14400 s at 3 mole/dm3 NaOH concentration, favoured the formation of hydrated calcium zincate phase and so decreased the leaching ratio of …