Dissolved Oxygen Concentration In Gold Leaching

25-12-2015· In simplified terms, the Effect of Oxygen on Gold Leaching can be summarized in saying: The dissolution rate of gold in alkaline cyanide

27-12-2017· The dissolution rate of the precious metals is thus closely related to the concentration of dissolved oxygen in the pulp. Extensive measurements

01-02-2004· The concentration of cyanide determines the rate of anodic dissolution of gold whilst the concentration of oxygen determines the cathodic reduction of oxygen. Thus the initial rate of gold dissolution is largely controlled by the factors such as cyanide and oxygen concentrations, pH and temperature.

Throughout the cyanidation process, dissolved oxygen levels varied between 5.5 and 8.5 mg/l, as measured with the Syland Dissolved Oxygen

01-06-1992· The cyanidation tests determined the effect of oxygen on leaching rate, total gold dissolution and cyanide consumption. The oxygen consumption for the superficial oxidation of the particles depends on the type and concentration of sulphide species in the ore, ranging from 5

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.

01-01-2017· Moreover, gold cyanidation can be enhanced by increasing concentration of the dissolved oxygen (DO). In general, the optimum concentration ratio of [CN-]/[O2] is calculated as 6, but it goes higher in the real system (Marsden &House, 2006), which means that the reaction is typically controlled by DO concentration."

Gold bullion is then recovered from the electrolyte by electrowinning. As a deficiency in dissolved oxygen in the solutions would slow the leaching speed, gaseous oxygen is bubbled through the slurry to increase the dissolved oxygen concentration. Intimate oxygen-slurry contactors are used to increase the partial pressure of

The cyanidation tests determined the effect of oxygen on leaching rate, total gold dissolution and cyanide consumption. The oxygen consumption for the superficial oxidation of the particles depends on the type and concentration of sulphide species in the ore, ranging from 5 to 150 g O 2 /h/t. Based on these results, plant measurements indicate,

Download scientific diagram | Effect of oxygen on gold leaching of a pyrrhotite-bearing gold ore (Cyanidation: pH 11.2, 200g/t Pb(NO 3 ) 2 , 32h) from publication: Cyanidation of a pyrrhotite,

Increased oxygen concentration enhanced Au dissolution from 0.04 to 0.16 mmol/l within the test period of 70 h. Electrochemical measurement clarified this phenomenon; the rest potential of Au in the cyanide solution produced by C. violaceum increased from -400 to -200 mV, while in the sterile cyanide solution, it was constant in cyanide,

The leaching behaviour of gold in the presence of sulphide minerals depends strongly on both the amount of dissolved sulphur and the oxygen concentration in solution (Dai and Jeffrey, 2006). Since the dissolution of sulphide minerals consumes oxygen, a reduction in the gold-leaching rate occurred associated with low dissolved

[ ] Complete gold recovery within a reasonable leaching time may only be achieved if the pulp is saturated with dissolved oxygen. Gold losses in leach operations mainly occur due to the following reasons: In some cases, the saturation of oxygen in the pulp cannot be achieved by aeration due to the difficulty to transfer oxygen from the gaseous into the liquid phase.

Oxygen is one of the reagents consumed during cyanidation, accepting the electrons from the gold, and a deficiency in dissolved oxygen slows leaching rate. Air or pure oxygen gas can be purged through the pulp to maximize the dissolved oxygen concentration. Intimate oxygen-pulp contactors are used to increase the partial pressure of the oxygen,

Dissolved Oxygen There must be sufficient entrained oxygen in the slurry. Increasing the oxygen concentration drives the reaction to the right. The flow of oxygen should be such,producing substances which can reduce the efficiency of gold leaching. Minerals that cause excessive consumption of cyanide are called cyanocides.

Gold bullion is then recovered from the electrolyte by electrowinning. As a deficiency in dissolved oxygen in the solutions would slow the leaching speed, gaseous oxygen is bubbled through the slurry to increase the dissolved oxygen concentration. Intimate oxygen-slurry contactors are used to increase the partial pressure of

Download scientific diagram | Effect of oxygen on gold leaching of a pyrrhotite-bearing gold ore (Cyanidation: pH 11.2, 200g/t Pb(NO 3 ) 2 , 32h) from publication: Cyanidation of a pyrrhotite,

25-03-2021· This process can increase the dissolved oxygen content in the slurry and therefore accelerate the leaching speed, improve the leaching rate of gold and the processing capacity. Oxygen is fed into the leaching tank from below the agitator and dissolved in the slurry. The concentration of oxygen in the slurry can be maintained at about 20×10-6.

18-07-2013· Gold leaching optimization studies were performed with one gold ore sample. Cyanide consumption was found to be strongly affected by the leaching pH and the “free” cyanide concentration in the slurry. High dissolved oxygen concentration as well as high lead nitrate addition,,

01-09-2017· 2.8 Effect of dissolved oxygen concentration on heap leaching process In cyanide solution, the dissolution rate of gold is proportional

[ ] Complete gold recovery within a reasonable leaching time may only be achieved if the pulp is saturated with dissolved oxygen. Gold losses in leach operations mainly occur due to the following reasons: In some cases, the saturation of oxygen in the pulp cannot be achieved by aeration due to the difficulty to transfer oxygen from the gaseous into the liquid phase.

gold leaching by Taguchi method, the sodium cyanide, pH, solid percent, d 80 and residence time parameters were chosen at two levels. The dissolved oxygen concentration in the pulp was obtained 6mg/l, which is due to the mixing condition, stirring speed, low volume of tests and dissolved oxygen during mixing at the lab scale,

This influence is 5 7. where gold dissolution rate has been plotted vs dissolved clearly illustrated in the 3D graph of Fig. 3. where cyanide oxygen and “free” cyanide concentration for lead nitrate consumption has been plotted vs leaching pH and cyanide con- additions of 0.0, 12.5 and 25.0 g/t, respectively.

The leaching behaviour of gold in the presence of sulphide minerals depends strongly on both the amount of dissolved sulphur and the oxygen concentration in solution (Dai and Jeffrey, 2006). Since the dissolution of sulphide minerals consumes oxygen, a reduction in the gold-leaching rate occurred associated with low dissolved

01-05-2003· Ammonium thiosulfate is a noncyanide lixiviant for gold leaching. However, the major problem with this leaching method has been the high consumption of reagents. To leach a mild-refractory copper-bearing gold ore, the authors used a reagent combination of 0.3M (NH4)2S2O3, 0.03M CuSO4 and 3M NH3 at pH 10.2 for 24 hours. In the testing, thiosulfate