hypochlorite leaching of gold ore 6821

Assessing the Similarity of Cyanide-Free Gold Leaching ...

10 Steps For Gold Leaching Using Environmental Gold Calcium peroxide sodium hypochlorite and sodium peroxide are all very stable and widely used multi-functional inorganic peroxides and have the characteristics of long-term oxygen release. In the leaching pulp oxygen can be slowly released for a long time which is

leaching process withacid

Table 2-1 Leaching systems for gold (J. T. Woodcock, 1988) 6 Table 2-2 - Properties and applications of leaching reagents for gold 7 Table 2-3 - List of gold minerals (R. W. Boyle, 1979) 10 Table 2-4 - Most common naturally occurring gold minerals (Marsden et al., 1992) 11 Table 2-5 Stability constants for some of the metal cyanide complexes 29

Hypochlorite Pretreatment of a Low Grade Carbonaceous Gold ...

A process for removing precious metals from comminuted ores. The process comprises the steps of first contacting comminuted ore with a primary acidic hypochlorite solution, separating the ore from the primary hypochlorite solution and then contacting the separated ore with an aqueous hypochlorite solution having a pH greater than 7.

Hypochlorite pretreatment in heap leaching of a low grade ...

Hypochlorite pretreatment of a refractory carbonaceous gold ore showed promise as a method for oxidizing sulfidic and carbonaceous materials prior to conventional cyanide heap leaching. However, previous studies showed hypochlorite consumption is high and gold extraction is proportional to hypochlorite consumption.

Leaching of an oxide gold ore with chloride/hypochlorite ...

If further leaching of gold by cyanidation or chloride-hypochlorite method is expected, then the process is carried out in a relatively neutral environment: at a pulp pH of more than 4.0. To neutralize sulfuric acid formed during oxidation by reactions (1) and (4), the cheapest reagent is used - limestone and (or) soda.

Leaching of an oxide gold ore with chloride/hypochlorite ...

Leach Gold Ore With Chlorination. Oct 06, 2015nbsp018332if the reading is less than 1000mv you need to add hypochlorite to get it up to 1000mv.when you add hypochlorite you will raise the ph so you will need to add hcl to get the ph back into range.if the redox is less than 1000mv you will start preferentially leaching base metals and will also precipitate out some of the already leached gold.

calcium hypochlorite for ore dressing

Gold cyanidation (also known as the cyanide process or the MacArthur-Forrest process) is a hydrometallurgical technique for extracting gold from low-grade ore by converting the gold to a water-soluble coordination complex.It is the most commonly used leaching process for gold extraction. In most cases, gold is often physically wrapped or incorporated into the various …

Hypochlorite pretreatment in heap leaching of a low grade ...

HYPOCHLORITE LEACHING OF GOLD ORE 7 1 Free Milling Gold Ore The free milling gold ore used in this study contains sulphide minerals, such as chalcopyrite and pyrite. Conventional cyanidation resulted in 95 % of the gold being extracted under strong leaching conditions, i.e., a grind of 90 % minus 200 mesh, leach with 1 g5 NaCN at pH 11.0 for

US4605537A - Sulfide as a hypochlorite kill agent - Google ...

The group of chemicals known as halides is composed of the elements fluorine, chlorine, bromine, and iodine. We will ignore fluorine because it does not

The leaching and adsorption behaviour of gold ores

Hypochlorite pretreatment in heap leaching of a low grade carbonaceous gold ore . By Mojtaba Ahmadiantehrani. ... 775-784-6945.The concept of hypochlorite treatment prior to cyanidation in the heap leaching of low grade carbonaceous gold ores is discussed and a brief operating cost evaluation is given Topics: metallurgy ...

US4439235A - Chlorination process for removing precious ...

Hypochlorite Leaching of Gold Ore - Free download as PDF File (.pdf), Text File (.txt) or read online for free. lixiviação alternativa do ouro

Gold Mine Heap Leaching Project in Paramaribo, Suriname

The gold dissolution rate at different conditions was determined using gold strips immersed in various mixtures of chloride/hypochlorite. Leaching experiments were conducted to test the extraction of gold from various ores (oxidised and copper-gold ores), showing a promising prospect for this technique in various applications.

The leaching of gold using nitrogen - and sulfur ...

Hypochlorite leaching system is a strong oxidizing solution for metal sulfides, which are naturally associated with gold extraction. This study evaluated the hypochlorite leaching of refractory gold ore by using the response surface method–central composite design (RSM-CCD) as a statistical approach in determining the optimum condition of gold extraction from refractory gold ore.

Process for the recovery of gold from an ore in chloride ...

The reactions between gold and hypochlorite leach solutions containing hydrochloric acid and sodium chloride are demonstrated below: 4Au + 16NaOCl + 10H2O → 4HAuCl4 ...

The leaching and adsorption behaviour of gold ores

Apr 21, 2020· The leaching of gold ore requires a pretreatment agent selection test. The pretreatment agents are mostly calcium peroxide, sodium hypochlorite, sodium peroxide, hydrogen peroxide, citric acid ...

Hypochlorite Leaching Of Gold Ore - Sisters Act,Johannesberg

kinetics, taking twice the time (46 h) to achieve maximum gold recovery of 58% compared to sodium hypochlorite. 10 g/L of total initial hypochlorite species in solution produces reasonable gold recoveries. The amount of added HCl and hence the initial pH was found to have a major effect on gold leaching kinetics and maximum gold recovery.

Extraction of Gold in Hallide Media - AusIMM

4.4 the effect of copper cyanide on gold leaching from oxide and sulphide ores 110 4.5 summary 114 chapters preg-robbing phenomena in the cyanidation of gold ores 116 5.1 objectives of this chapter 116 5.2 background information 116 5.3 preg-robbing behaviour by the ores at …

Determination of the mechanism of the chlorination of gold ...

Residual hypochlorite contained in chlorinated slurries of either carbonaceous gold-containing ores or mixtures of carbonaceous and oxide gold-containing ores are reduced by reaction with sulfide ion-providing chemical compounds preferably sodium hydrosulfide, sodium sulfide or hydrogen sulfide. The hypochlorite "kill" step enables subsequent cyanide leach operations …

4 Reasons and Solutions of Poor Gold Leaching Effect

The invention claimed is: 1. A cyanide-free process for recovery of gold from an ore comprising the steps of: i) providing the ore comprising the gold to be recovered; ii) leaching the ore in a chloride oxidative medium, comprising nitric acid to produce a chloride solution comprising gold; and iii) recovering the gold from the chloride solution, wherein recovering the gold from the …

Hypochlorite pretreatment in heap leaching of a low grade ...

rite. Such deposits are called refractory gold ores due to the encapsulation of fine particles of gold in the ore host. A clear boundary between refractory and non-refractory ore in terms of gold recovery is not well defined, but several authors have pointed out that less than 60% gold recovery by direct cyanide leaching, after fine grinding

Process for the recovery of gold from an ore in chloride ...

This rate is much higher than the gold dissolution rate of 2.5 mg/cm 2 h obtained in 2 g/L of cyanide solution (Tran et al., 2001).The performance of chloride/hypochlorite solution for gold leaching also depends on major minerals present in the ore.

THE CYANIDE HEAP LEACHING BEHAVIOR OF CUPRIFEROUS …

4.4 the effect of copper cyanide on gold leaching from oxide and sulphide ores 110 4.5 summary 114 chapters preg-robbing phenomena in the cyanidation of gold ores 116 5.1 objectives of this chapter 116 5.2 background information 116 5.3 preg-robbing behaviour by the ores at low cyanide ...

Flexicone technology for sulfide ores | flexicone

Hypochlorite leaching system is a strong oxidizing solution for metal sulfides, which are naturally associated with gold extraction.

Recovery of Platinum, Palladium, and Gold From Stillwater ...

4.4 the effect of copper cyanide on gold leaching from oxide and sulphide ores 110 4.5 summary 114 chapters preg-robbing phenomena in the cyanidation of gold ores 116 5.1 objectives of this chapter 116 5.2 background information 116 5.3 preg-robbing behaviour by the ores at …

Leaching of an oxide gold ore with chloride/hypochlorite ...

Pretreatment Process on Refractory Gold Ores with As. Bacterial oxidation process to leach gold is roughly divided into three stages: (1) using bacteria culture medium to cultivate thiobacillus ferroxidans, etc. and preparation for sulfuric acid bacteria leaching solution of Ph=1.5–2.5; (2) bacteria catalyzing, oxidizing and re-moving arsenic and sulfur; (3) the residue from …

(PDF) Chloride-hypochlorite oxidation and leaching of ...

The invention claimed is: 1. A cyanide-free process for recovery of gold from an ore comprising the steps of: i) providing the ore comprising the gold to be recovered; ii) leaching the ore in a chloride oxidative medium, comprising nitric acid to produce a chloride solution comprising gold; and iii) recovering the gold from the chloride solution, wherein recovering the gold from the …

How to Improve the Effect of Gold Cyanidation Process

Pretreatment Process on Refractory Gold Ores with As. Bacterial oxidation process to leach gold is roughly divided into three stages: (1) using bacteria culture medium to cultivate thiobacillus ferroxidans, etc. and preparation for sulfuric acid bacteria leaching solution of Ph=1.5–2.5; (2) bacteria catalyzing, oxidizing and re-moving arsenic and sulfur; (3) the residue from …

leaching process withacid

Apr 24, 2017· Bleach is the chemical compound sodium hypochlorite. When combined with hydrochloric acid, the mixture produces chlorine that dissolves gold from gold ore. This was the first commercial method used for gold extraction. Place the ore …

Sodium hypochlorite pretreatment for heap leaching gold ore

10 Steps For Gold Leaching Using Environmental Gold Calcium peroxide sodium hypochlorite and sodium peroxide are all very stable and widely used multi-functional inorganic peroxides and have the characteristics of long-term oxygen release. In the leaching pulp oxygen can be slowly released for a long time which is

Leaching of an oxide gold ore with chloride/hypochlorite ...

Chloride–hypochlorite oxidation and leaching of refractory sulfide gold concentrate 63 Fig. 1. The Pourbaix diagram of Fe–S at [Fe] –= 10 4 M, [S] = 10– M and 25 C (the chlorine species regions are also marked) (Marsden and House, 2005) Fig. 2.

How to Use Bleach on Gold Ore to Remove Gold | Sciencing

In this paper, gold leaching of a refractory sulfide concentrate by chloride–hypochlorite solution was investigated and effects of stirring speed, temperature and particle size on the leaching ...

Advances in Gold and Silver Processing

If the gold ore is still difficult to be successfully leached after being finely ground, the gold ore is called refractory gold. Generally, the grade of Au in the tailings is greater than 0.5g/t. The gold in this type of ore, either physically wrapped or chemically combined, cannot be in contact with the cyanide solution, so it is difficult to ...

The leaching and adsorption behaviour of gold ores

The leaching of gold using less corrosive fluids without significant losses in the dissolution rate of the metal. 19 C.p. f-crystals, 6 tables, 4 Il. The invention relates to the field of dissolution of metallic gold leaching solution, especially for the hydrometallurgical recovery of gold from ore.

Method of gold extraction from sulphide gold-bearing ores

What is claimed is 1. A method of treating carbonaceous gold ores to prevent absorption of Au(CN)-2 during a subsequent cyanide leach comprising treating an aqueous slurry of said ore with an alkaline hypochlorite from the group consisting of sodium hypochlorite and calcium hypochlorite at a temperature of less than 70° C. 2. The method of claim 1 wherein the alkaline hypochlorite …

Hypochlorite Leaching Of Gold Ore - Sisters Act,Johannesberg

4.4 the effect of copper cyanide on gold leaching from oxide and sulphide ores 110 4.5 summary 114 chapters preg-robbing phenomena in the cyanidation of gold ores 116 5.1 objectives of this chapter 116 5.2 background information 116 5.3 preg-robbing behaviour by the ores at …

(PDF) Chloride-hypochlorite oxidation and leaching of ...

Chloride–hypochlorite oxidation and leaching of refractory sulfide gold concentrate 63 Fig. 1. The Pourbaix diagram of Fe–S at [Fe] –= 10 4 M, [S] = 10– M and 25 C (the chlorine species regions are also marked) (Marsden and House, 2005) Fig. 2.

bacterial heap leaching of refractory gold sulphide ores

The invention relates to hydrometallurgy of precious metals and can be used for the extraction of gold from refractory ores and concentrates. For multi-stage technology of gold extraction plant for intrusion resistant gold-bearing ores has developed a number of pyro-and hydrometallurgical methods, while bacterial leaching shows good economic performance and environmental …

bacterial heap leaching of refractory gold sulphide ores

An oxide gold ore was subjected to chloride/hypochlorite leaching at room temperature. The effects of three factors, including Ca(OCl)2 vs. NaOCl, OCl− concentration, and HCl concentration on ...

RECOVERY OF GOLD FROM CARBONACEOUS ORES - INTERIOR USA

peroxide, chlorine, sodium hypochlorite, nitric acid, and a persulfate salt were the oxidants investigated. The two-stage leaching scheme ex­ tracted up to 97 pct of the platinum, 92 pct of the palladium, and 99 pct of the gold from the roasted concentrate. The base metals were not solubilized and reported to the residue.

Optimization Process of the Refractory Gold Ore Extraction ...

The article emphasizes the urgent need of heap leaching in the current geotechnical conditions. The application prospects for heap leaching are connected with preliminary oxidation of refractory ore. Another important requirement is geo-engineering typification of ore through geotechnical mapping. An alternative of cyanide in gold leaching is chlorine compounds.