scholarly journals Study of the process of cyanide leaching of gold using sodium acetate at different ore sizes

2020 ◽  
Vol 1 (312) ◽  
pp. 59-68
Author(s):  
Ye. K. Yessengarayev ◽  
◽  
B.S. Baimbetov ◽  
S. V. Mamyachenkov ◽  
B. N. Surimbayev ◽  
...  
Keyword(s):  
Sodium Acetate ◽  
Gold Recovery ◽  
Metal Extraction ◽  
Cyanide Leaching ◽  
Electron Probe Analysis ◽  
Granulometric Analysis ◽  
Complete Extraction ◽  
Crushed Ore ◽  
Kinetics Of ◽  
Technical Measures

Intensification of metal extraction by leaching is a complex of organizational and technical measures aimed at achieving the fastest and complete extraction of metal from ore. Measures to intensify leaching are aimed at completely or partially neutralizing the causes that cause a decrease in the leaching rate. Tests were performed on cyanide leaching of gold from gold-containing ore with the addition of sodium acetate to intensify the leaching process. The results of assay-gravimetric, chemical, mineralogical and granulometric analysis of oxidized ore are presented. According to electron-probe analysis, gold in the ore is present in the form of thin (micron) inclusions in minerals and ore rocks. A study was conducted on leaching of crushed ore with a size of 90% of the class -0.074 mm and crushed ore with a size of -12+0 mm. Leaching of crushed ore with a size of 90% of the class -0.074 mm showed that when adding sodium acetate, the gold recovery rate increases by 1.13 % compared to leaching without adding this reagent. When leaching crushed ore with a size of -12 + 0 mm with the addition of acetate, gold recovery increases by an average of 4 %, and the kinetics of gold dissolution improves. Research data prove that sodium acetate can be used to intensify gold at a ore size of -12+0 mm and in larger ore classes for leaching gold.

scholarly journals Studies on heap leaching of gold with the addition of sodium acetate as an intensifying reagent

2020 ◽  
pp. 25-30
Author(s):  
Ye. K. Yessengarayev ◽  
B. S. Baimbetov ◽  
B. N. Surimbayev
Keyword(s):  
Sodium Acetate ◽  
Heap Leaching ◽  
Gold Recovery ◽  
Gold Content ◽  
Electron Probe Analysis ◽  
Crushed Material ◽  
Urgent Task ◽  
Cyanide Consumption ◽  
Crushed Ore ◽  
Gold Bearing

One of the cheapest methods of extracting gold is heap leaching. However, the recovery of gold by this method is relatively low, compared with cyanidation of the crushed material, so the search for the ways to intensify leaching and increase gold recovery is an urgent task. Investigations on heap leaching of gold from the gold-bearing ore of the Sari Gunay deposit were conducted using a promising reagent sodium acetate to intensify the heap leaching process. The results of assay-gravimetric, chemical, mineralogical and granulometric analyses of oxidized ore are presented. The average gold content in the ore was 2.90 g/t. According to the electron probe analysis, gold in the ore is present in the form of fine (micron) inclusions in minerals and ore rocks. Comparative studies on heap leaching of gold from the crushed ore with a grain size of –20 + 0 mm with the addition of sodium acetate and without that were carried out. The degree of gold recovery with sodium acetate at a flow rate of 0.5 kg/t was 58.74%, that without sodium acetate was 54.69%, i.e. the addition of the reagent provides an increase in recovery of more than 4%. Leaching with the addition of the reagent also reduces sodium cyanide consumption from 0.65 to 0.59 kg/t. The research results have shown that sodium acetate can be used to intensify the process of heap leaching of gold when the ore size is –20+0 mm.

Applicability of electrodialysis to the separation of sodium acetate from synthetic alkaline hardwood extract

TAPPI Journal ◽  
2015 ◽  
Vol 14 (11) ◽  
pp. 695-708 ◽  
Author(s):  
RAVIKANT PATIL ◽  
CHI TRUONG ◽  
JOSEPH GENCO ◽  
HEMANT PENDSE ◽  
ADRIAAN VAN HEININGEN
Keyword(s):  
Current Density ◽  
Sodium Sulfate ◽  
Sodium Acetate ◽  
Separation Efficiency ◽  
Feed Concentration ◽  
Initial Concentration ◽  
White Liquor ◽  
Complete Extraction ◽  
Electro Osmosis ◽  
Preliminary Separation

Our objective was to develop a process for recovering acetyl groups from industrial northeast hardwood chips. Extraction experiments showed that the white liquor charge of 6% effective alkali at 50°C and liquor-to-wood ratio of 4:1 leads to the complete extraction of acetyl groups from industrial hardwood chips. Electrodialysis was assessed as a technique for separating and concentrating sodium acetate from synthetic hardwood extract. Preliminary separation experiments using dilute sodium acetate showed that the sodium acetate can be concentrated up to approximately 24% by weight from an initial concentration of about 2% by weight. The effects of current density, feed concentration, electro-osmosis, and osmosis on the separation of sodium acetate were evaluated. Finally, selectivity experiments were performed to study the effect of various components of the white liquor on the separation of sodium acetate. Fully oxidized synthetic white liquor was used in selectivity experiments to avoid deleterious effects of Na2S. Selectivity experiments using synthetic oxidized white liquor showed a significant decrease in the separation efficiency due to the presence of sodium hydroxide, sodium carbonate, and sodium sulfate in the synthetic extract.

scholarly journals Kinetics of metal extraction in ionic liquids: Eu3+/HNO3//TODGA/[C1C4im][Tf2N] as a case study

RSC Advances ◽  
2013 ◽  
Vol 3 (27) ◽  
pp. 10736 ◽  
Author(s):  
Michal Sypula ◽  
Ali Ouadi ◽  
Clotilde Gaillard ◽  
Isabelle Billard
Keyword(s):  
Ionic Liquids ◽  
Metal Extraction ◽  
Kinetics Of

Leaching kinetics of copper and valuable metal extraction from copper-cadmium residues of zinc hydrometallurgy by oxidation acid leaching

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Jihao Guo ◽  
Hongao Xu ◽  
Bo Li ◽  
Yonggang Wei ◽  
Hua Wang
Keyword(s):  
Hydrogen Peroxide ◽  
Acid Concentration ◽  
Acid Leaching ◽  
Metal Extraction ◽  
Agitation Rate ◽  
Leaching Kinetics ◽  
Solid Ratio ◽  
Zinc Hydrometallurgy ◽  
Kinetics Of ◽  
Leaching Efficiency

Abstract Multiple purification of zinc sulfate solution is an important process for zinc hydrometallurgy, and large quantities of copper-cadmium residues are generated as byproducts in this process. Copper-cadmium residues contain a large number of valuable metals that must be recovered. A comprehensive extraction process has been proposed using sulfuric acid as the leaching reagent and hydrogen peroxide as the oxidizing reagent. The effects of acid concentration, leaching temperature, leaching time, liquid-to-solid ratio, hydrogen peroxide dosage and stirring speed on the leaching efficiency were investigated. The optimum conditions were determined as an acid concentration of 150 g/L, liquid-to-solid ratio of 4:1, hydrogen peroxide amount of 20 mL, time of 60 min, temperature of 30 °C, particle size of −d75 μm, and agitation rate of 300 r/min. It was concluded that the leaching efficiency of copper and cadmium reached 97%, but because of the existence of zinc sulfide in the residues, a lower leaching efficiency of zinc was obtained. Furthermore, the leaching kinetics of copper was also studied based on the shrinking core model. The activation energy for copper leaching was 5.06 kJ/mol, and the leaching process was controlled by the diffusion through the product layer.

Equilibria between Palladium(II) Acetate and Olefins in Acetic Acid containing Sodium Acetate

1975 ◽  
Vol 53 (12) ◽  
pp. 1833-1841 ◽  
Author(s):  
Raj N. Pandey ◽  
Patrick M. Henry
Keyword(s):  
Acetic Acid ◽  
Sodium Acetate ◽  
Solution Composition ◽  
Kinetics Of Oxidation ◽  
Complex Equilibria ◽  
Π Complex ◽  
Allylic Esters ◽  
Kinetics Of

π-Complex equilibria between dimeric Pd(II) acetate and various olefins (ethylene, styrene, 3,3-dimethyl-1-butene, vinylic and allylic esters) in acetic acid solvent have been investigated by spectral means. The results indicate two π-complexes are formed. The first π-complex, which is formed rapidly, is a dimeric π-complex (ol = olefin ).[Formula: see text]The Benesi–Hildebrand plots for these complexes are linear for all olefins and thus values of Kπ22 can be readily evaluated. The values of the equilibrium coefficient, Kπ22, do not change with solution composition or [NaOAc]. The second π-complex is formed slowly. The data are consistent only with the equilibrium[Formula: see text]The data are inconsistent with the equilibrium[Formula: see text]which is analogous to that reported for the Na2Pd2Cl6 reaction with olefins in acetic acid. Furthermore, previous assumptions as to the equilibria between ethylene and Pd(II) in the all-acetate system have proved incorrect, and so the kinetics of oxidation of ethylene in this system must be reinterpreted in view of the present results.

Sign in / Sign up

Export Citation Format

Share Document