pretreatment of refractory sulphide gold ores and concentrates. Refractory gold ore pretreatment Treatment of refractory gold ore (whole ore and flotation concentrates) has become more prominent since the 1980s with many gold discoveries often including ores that are wholly or partially refractory.
Metallurgical ContentGold Leaching & Processing of Arsenic OreMispickel (Arsenopyrite: FeAsS).6Leaching and Recovering Gold from Antimony MineralsStibnite (Antimony Sulphide, Sb2S2)Telluride Gold Ore ProcessingSolubility of TelluridesGold Extraction from Carbonaceous OreList Gold Refractory Process Methods Where gold is associated with arsenic, antimony, tellurium, and …
pretreatment of refractory gold ore ellul.nl. Effect of Pretreatment of Sulfide Refractory Concentrate For extraction of gold from refractory ores or concentrate, in which gold is surrounded or covered by iron sulfide minerals, mainly arsenopyrite and pyrite, mineral oxidative pretreatment is essential to oxidize sulfides and to expose gold ...
Mrkusic, P. G., and J. E. Laschinger. 1967. Refractory gold ores—report on investigations into roasting of gold concentrates in the Edwards roaster of the Fairview and the New Consort reduction plants. Nat. Inst. of Metallurgy, Report No. 211, Johannesburg. Google Scholar
Request PDF on ResearchGate | Pre-treatment of a refractory gold sulfide ore by means of Acidithiobacilli cells | Cyanidation is a relatively simple and cheap technology to treat gold-containing ores.
Many of the gold deposits contain finely disseminated gold in iron sulfide minerals such as pyrite and arsenopy- 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
The problem of refractory sulfide gold ore that has a gold recovery less than 50% when direct cyanidation applied, still exists until now. It needs oxidative pretreatment for cyanidation to be effective in gold recovery the objective of this study is figuring out the effect of sodium nitrite as an oxidizing reagent on cyanidation of refractory gold ore.
Effect of Pretreatment of Sulfide Refractory Concentrate ... The majority of the refractory gold and silver occurs in occlusion in sulphides, then precious metal dissolution is possible by first oxidizing auriferous sulfide concentrate using sodium hypochlorite-sodium-hydroxide solution followed of pressure cyanidation of the oxidized concentrate, for the extraction of precious metals.
Effect of Pretreatment of Sulfide Refractory Concentrate ... For extraction of gold from refractory ores or concentrate, in which gold is surrounded or covered by iron sulfide minerals, mainly arsenopyrite and pyrite, mineral oxidative pretreatment is essential to oxidize sulfides and to expose gold to the leaching solution.
Pre-treatment of refractory gold concentrates 865 Roasting and cyanidation The roasting tests were carried out to confirm the gold recovery values obtained at the Roasting Plant. Exactly 566.5g of the concentrate was blended with 133.5g of silica to give a blend roast charge of 700g assaying 65.4g/t.
reagent on cyanidation of refractory gold ore. Cyanide leaching of the concentrate was performed at 20%-w/w of solid (500 gram of refractory sulfide gold ore concentrate) in a 2.5-liter glass reactor with aeration and stirred at 250 rpm. Leach solutions were prepared using deionized-distilled water at the prescribed concentration of reagents.
Hydrometallurgy 105 (2011) 234–239 Contents lists available at ScienceDirect Hydrometallurgy j o u r n a l h o m e p a g e : w w w. e l s ev i e r. c o m / l o c a t e / h yd r o m e t Improved gold and silver extraction from a refractory antimony ore by pretreatment with alkaline sulphide leach Oktay Celep, İbrahim Alp ⁎, Hacı Deveci ...
The BIOX® process involves bacterial oxidation in agitated tanks for pre-treatment of refractory ores and concentrates ahead of conventional cyanide leach for gold recovery. Under controlled continuous plant conditions, the number of bacterial cells and their activity is optimised to attain the highest rate of sulfide oxidation.
research is conducted on the removal of residual sulphur from refractory gold bearing bioleach residue through the application of bio-oxidation, where sulphur is oxidized at different temperatures and pH levels to form sulphuric acid. Refractory sulphide ores and concentrates often consume large
submicroscopic gold inclusions within sulphide minerals such as arsenopyrite and pyrite. Such ores require a pre-treatment process to alter or destroy the sulphide matrix and render the gold accessible to cyanide and oxygen (Gudyanga et al., 1999). The gold in high-sulphur and high-arsenic refractory gold concentrate (HGC) is encapsulated
Microbial Pretreatment of Refractory Gold Ore - Xinhai. For coarse grain size of gold after crushing and grinding by flotation, gravity concentration, cyanide leaching process or several process combined treatment will be able to complete the separation of gold and gangue minerals
The result of the novel microbial pre-treatment process indicated that sulfide sulfur was degraded under alkaline conditions and carbonaceous matter passivated by T. versicolor at its optimum growth conditions. This led to a significant improvement in gold extraction from the double refractory gold ore and concentrate investigated.
Refractory gold ores are those that do not yield high gold recoveries in conventional cyanide-leaching circuits, even when the ore is finely ground. The cause of low gold recoveries can be either through the presence of naturally occurring 'preg robbing' carbonaceous materials or gold physically 'locked' in sulphide minerals.
Effect of Pretreatment of Sulfide Refractory Concentrate with Sodium Hypochlorite, Followed by Extraction of Gold by Pressure Cyanidation, on Gold Removal ... is of practical and theoretical importance in processing Arsenopyrite oxidation rate depends on the concentra- gold ores and concentrates. However, the chemistry of tions of oxygen and ...
An attempt has been made to study the pretreatment of sulfidic refractory gold ore with pyrolusite. The inﬂuences of various parameters were studied to optimize the conditions.
Bacterial oxidation of refractory sulfidic gold ores and concentrates can be used as a pretreatment process to enhance the recovery of gold. Sulfide minerals that occlude gold, such as pyrite, arsenopyrite, pyrrhotite, and marcasite, are biooxidized by acidophilic, chemolithotrophic bacteria.
Recovery of gold in sulfide ores has fallen into several categories. First is froth flotation, and second is cyanidation of the ores. Using cyanide to recover gold from sulfide ores generally results in 30 to 35% recovery, and the best I have heard of is around 50% recovery.
This study assessed the capability of the fungus, Phanerochaete chrysosporium, to decompose pyrite, arsenopyrite and a sulfide-containing flotation concentrate in an effort to develop a microbial process for pretreating refractory gold ores.The extent of biotransformation was monitored by analyzing for iron, sulfur and arsenic in incubation solutions, and for sulfide sulfur in the residual solids.
mainly about the refractory gold leaching easily through arsenic removal to expose gold, changing the composition, physic-chemical and electro-chemical properties of the ore. Currently, there are four main methods of pretreatments of refractory gold ores with As. Pretreatment options for deal-ing with refractory gold ores are illustrated in Fig ...
Chloride–hypochlorite oxidation and leaching of refractory sulfide gold concentrate 65 Fig. 3. Particles size analysis of gold concentrate Fig. 4. XRD analysis of gold concentrate obtained by flotation Table 1. Major elements composition of the ore and floated concentrate
Refractory gold ore pretreatment Treatment of refractory gold ore (whole ore and flotation concentrates) has become more prominent since the 1980s, with many gold discoveries often including ores that are wholly or partially refractory. Refractory pre-treatment processes include pressure oxidation, biological oxidation and various forms of ...
Significant advances have taken place in the treatment of refractory gold ores and concentrates during the past decade. In sulfide ores, pyrite is the most common host mineral for gold. Studies by Gasparrini (1983) showed that gold occurs in pyrite as native gold or electrum in all sizes and forms. Arsenopyrite is probably the second most common host for gold and forms similar associations ...
Acid pressure oxidation is generally believed to be the most effective pretreatment for refractory sulfide gold ores and concentrates, although it is ineffective for some ores. For such ores and concentrates (usually those containing both carbonaceous and sulfide materials), roasting remains the most effective pretreatment before cyanidation.