Effects of sulphide minerals and dissolved oxygen on the gold and silver dissolution in cyanide solution

Liu, G.Q.; Yen, W.T.

doi:10.1016/0892-6875(94)00107-n

Cited by 41 publications

(12 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…According to the mixed potential theory of [CN − ]/[O 2 ], the optimal concentration ratio of [CN − ]/[O 2 ] was determined on the basis of the anodic oxidation of gold; the cathodic reduction of oxygen should be performed at the same rate. According to Fick's law calculation, the molar ratio of free cyanide to oxygen in the solution is approximately 6:1 when the dissolution rate of gold reaches a maximum [8]. The above-mentioned theories confirm that appropriate concentrations of [CN − ]/[O 2 ] improve the gold leaching rate, which is consistent with the previously analyzed effect of [CN − ]/[O 2 ] on the cyanide leaching of gold.…”

Section: Qcm-d Monitoring Of the Effect Of [Cn − ]/[O 2 ] On The Cyanide Leaching Of Goldsupporting

confidence: 85%

“…The two sources of oxygen during cyanide heap leaching are dissolved oxygen (DO) in the feed solution and gaseous oxygen in the heap interspace [7]. In the cyanide heap leaching of gold ore, associated minerals, such as copper sulfide and pyrite, consume abundant oxygen [8]. As the ore heap height gradually increases over time, the liquid flows from the top through the particles in preferential flow paths, limiting the reaction at the bottom of the heap [9].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Ozone Ice as an Oxygen Release Reagent for Heap Leaching of Gold Ore

et al. 2021

View full text Add to dashboard Cite

The issue of poor aeration efficiency and low oxygen transfer in the heap leaching of gold has gained considerable attention. In this study, ozone ice was studied as an oxygen release reagent in the cyanide heap leaching of gold at a low temperature of approximately 5 °C, owing to its effective oxidation and clean and green properties. Quartz Crystal Microbalance with Dissipation (QCM-D) was used to monitor the effect of different ratios of cyanide and oxygen concentrations on the gold leaching rate. The results showed that the leaching rate doubled when the dissolved oxygen (DO) was increased from 8.2 mg/L to 12 mg/L at a relatively high cyanide concentration of 60 mg/L. The release of oxygen during the process of ozone ice melting was analyzed by simulating the oxygen-deficient condition of the ore heap in column leaching. In the first stage of ice melting, the DO in the solution increased dramatically, and the rate of increase improved with increased initial ozone concentration in the ice. In the second stage of ice melting, the rate of increase in the DO of the solution was not significantly affected by the initial ozone concentration in the ice; this was consistent with the decomposition rate of ozone. The addition of ozone ice containing 300 mg/L ozone increased the gold extraction by 4.1% in the ore column leaching experiment, compared to a column with no ozone ice. However, continuously increasing the ozone concentration up to 600 mg/L had no further significant effect, because the dissolved oxygen in the leaching solution reached saturation. The results facilitate a better understanding of the decomposition law of ozone in the melting process of ozone ice and help to improve the oxygen deficit state in gold leaching heaps.

show abstract

Section: Qcm-d Monitoring Of the Effect Of [Cn − ]/[O 2 ] On The Cyanide Leaching Of Goldsupporting

confidence: 85%

Section: Introductionmentioning

confidence: 99%

Ozone Ice as an Oxygen Release Reagent for Heap Leaching of Gold Ore

et al. 2021

View full text Add to dashboard Cite

show abstract

“…The cyanidation process for gold ore is described by Elsner's equation as Eq. 1, in which oxygen plays an important role in gold cyanidation (Liu and Yen, 1995). Later studies suggested that the cyanidation process occurs in two steps: O2 is reduced and hydrogen peroxide (H2O2) is formed at the beginning of the reaction as Eq.…”

Section: Introductionmentioning

confidence: 99%

Effect of hydrogen peroxide and lead(II) nitrate on gold cyanide leaching of Malaysian mesothermal deposit gold ore

Baharun¹,

Ling²,

Ardani³

et al. 2020

Physicochem. Probl. Miner. Process.

View full text Add to dashboard Cite

The gold extraction from Malaysian mesothermal lode gold ore through the cyanidation method was performed. The effect of hydrogen peroxide (H2O2) and lead nitrate Pb(NO3)2 were investigated on the percentage of gold recovery. The statistical analysis method using a response surface design-central composite design was applied to find the optimum condition for gold extraction. The studied parameters were NaCN concentration (300-500 ppm), H2O2 concentration (205-410 ppm), and Pb(NO3)2 concentration (50-150 ppm). It was found that increasing the amount of NaCN and H2O2 as well as decreasing the amount of Pb(NO3)2 in the studied range, increased the gold recovery. The analysis of variance suggested the linear model for the gold extraction with the optimum condition at 467.3 ppm NaCN, 94.96 ppm Pb(NO3)2, and 340 ppm H2O2. The gold extracted from the ore at the optimum condition was 88.97% as compared to 62.02% from conventional cyanidation. The characterization study of the gold ore indicated that the finely gold particles interlocked in the aluminosilicate phase (grain size of ~10.0 µm). The Van't Hoff differential method justified that the cyanidation was of second order with a specific reaction rate of 0.0501/hour.

show abstract

“…[8] A literature survey shows that few from which the extraction fraction of silver was calculated. articles reported on the leaching kinetics of silver in sulfuric acid solution, although there are many investigations on the kinetics of silver leaching in cyanide, [9][10][11][12] thiourea, [13,14,15] III. RESULTS AND DISCUSSIONS halide, [16,17,18] nitric acid, [19] ammonia, [20,21] and thiosulfate [22] systems.…”

Section: Introductionmentioning

confidence: 99%

Kinetics of silver leaching from manganese-silver associated ores in sulfuric acid solution in the presence of hydrogen peroxide

Jiang

Yang

Huang

et al. 2002

Metall Mater Trans B

View full text Add to dashboard Cite

Kinetics of silver leaching from a manganese-silver associated ore in sulfuric acid solution in the presence of H 2 O 2 has been investigated in this article. It is found that sulfuric acid and hydrogen peroxide have significant effects on the leaching rate of silver. The reaction orders of H 2 SO 4 and H 2 O 2 were determined as 0.80 and 0.68, respectively. It is found that the effects of temperature on the leaching rate are not marked, the apparent activation energy is attained to be 8.05 kJ/mol within the temperature range of 30 ЊC to 60 ЊC in the presence of H 2 O 2 . Silver leaching is found to be diffusion-controlled and follows the kinetic model: 1 Ϫ 2x/3 Ϫ (1 Ϫ x) 2/3 ϭ Kt. It is also found that particle size presents a clear effect on silver leaching rate, and the rate constant (k) is proportional to d 0Ϫ2 .

show abstract

Effects of sulphide minerals and dissolved oxygen on the gold and silver dissolution in cyanide solution

Cited by 41 publications

References 1 publication

Ozone Ice as an Oxygen Release Reagent for Heap Leaching of Gold Ore

Ozone Ice as an Oxygen Release Reagent for Heap Leaching of Gold Ore

Effect of hydrogen peroxide and lead(II) nitrate on gold cyanide leaching of Malaysian mesothermal deposit gold ore

Kinetics of silver leaching from manganese-silver associated ores in sulfuric acid solution in the presence of hydrogen peroxide

Contact Info

Product

Resources

About