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
Nov 28, 2016· The reason of the gold mineral refractory There are so many types of reasons that caused the difficulty of gold ore processing, including physical element, chemical element, and mineralogical element.
Jul 16, 2016· Abstract. Carbonate decomposition of carbonic refractory gold ore and the following pressure oxidation were studied. In the carbonate decomposition procedure, the effects of liquid-to-solid ratio and reaction time on decomposition ratio of carbonate were investigated.
In the recovery of gold from refractory gold ores, pretreatment is required to decompose sulphides and liberate occluded gold before cyanidation, and to deactivate carbonaceous matter and prevent it from adsorbing dissolved gold. Until the past three decades, most commercial pretreatment processes had been by abiotic means.
PRESSURE OXIDATION OF REFRACTORY GOLD ORES: THE METATES GOLD PROJECT EXPERIENCE . By . 1Gary Parkison, 2Art Ibrado, 3Grenvil Dunn, 3Nelson Mora and 3Yong Yong Teo . 1Chesapeake Gold Corp., Canada . 2M3 Engineering and Technology, USA . 3. Orway Mineral Consultants (WA) Pty Ltd, Australia . Corresponding Author
Dec 11, 2008· The oxidative leaching period depends on the amount of ore being leached. Larger quantities of ore require longer leach periods. For low grade ores used during this experiment, an oxidative leaching period of 1 to 6 hours was found to be adequate. However, for higher grade ore or refractory ore, a longer leaching period should be selected.
Improvements in gold ore cyanidation by pre-oxidation with hydrogen peroxide. ... M.I. Muravyov, A.G. BulaevTwo-step oxidation of a refractory gold-bearing sulfidic concentrate and the effect of organic nutrients on its biooxidation. Miner. Eng., 45 (May) (2013), pp. 108-114
Peroxide dilution with water was carried out in the main feed pipe. mainly for: effluent detoxification/ ‘‘very low” (fluctuating around 0. the opening up of the ore.4 ppm in the first cyanidation tank (Tank 4)). high 2.0 ppm in the pre-oxidation neutralization of spent heaps (Botz et al. well below (1) It is an aqueous liquid oxidant ...
Nov 16, 1993· A method of recovering precious metals from a silver bearing ore containing polybasite, pearcite, pyrargyrite, tetrahedrite or argentite by mixing the ore with an alkali metal or alkaline earth metal peroxide in slurry or solid, leaching the ore with a cyanide solution, and recovering the precious metals from the cyanide solution.
The influence of pyrite pre-oxidation in alkaline solutions on gold recovery by cyanidation from Twin Creek refractory gold ore in which pyrite was identified as the major sulfide mineral has been ...
Jun 06, 2015· Here is a simplified presentation of how gold can be obtained from refractory gold ores using a combination of flotation and bacterial oxidation using thiobacillus ferroxidans.
The preoxidation of refractory gold ore by a mixed culture of moderately thermophilic bacteria also was investigated in this equipment. The results showed that, under the conditions of pulp density 8% and stay time 60h, it can deal with 0.256 kg refractory gold ore per …
This paper summarizes the result of experiment that was fourced on investigation of oxidation pretreatment on sulfide mineral for leaching of refractory gold concentrate by hydrogen peroxide in sulfuric acid. For a viable option, extraction rate of Fe, Cu was low, but extraction rate of arsenic reached nearly . As the result of oxidation, elemental sulfur was not produced.
Apr 07, 2015· Chemical Used in Gold Mining - Refractory Gold Ores The gold also occurs as sub microscopic particles in sulphides or as absorbed gold onto surfaces of carbonaceous matter. Because of the variation of these refractory ores, gold occurrence is ore specific and before process decisions are made, competent mineralogical and metallurgical ...
Critical Reviews in Biotechnology, 12(1/2):133155(1992) Bacterial Oxidation of Refractory Sulfide Ores for Gold Recovery E Borje Lindstrom. Pressure oxidation Wikipedia. Pressure Oxidation is a process for extracting gold from refractory ore The most common refractory ores are pyrite and arsenopyrite, which are sulfide ores that trap .
oxidation, bio oxidation and roasting, for specific ores bodies (1-4). More recent technologies such as the Albion Process can be potentially comparable or lower cost compared with the conventional technologies (5). The most significant item affecting the economics is the amenability of the ore to
Researchers about biooxidation "In refractory ores, small particles of gold are covered by insoluble sulfides impeding the contact between cyanide and gold. In this case, a pretreatment stage must be considered, such as pressure oxidation, chemical oxidation, roasting or bio
The oxidation may also open up the fissure planes, setting free the associated gold. This oxidation may be secured by “weathering” the ore pulp, but in some cases, the agitation of the wet pulp with small amounts of lime and sodium peroxide, together with injected air prior to …
Hydrogen Peroxide Catalytic Oxidation of Refractory Organics in Municipal Waste Waters. D. F. Bishop, G. Stern, M. Fleischman, ... Catalytic Wet Peroxide Oxidation Technique for the Removal of Decontaminating Agents Ethylenediaminetetraacetic Acid and Oxalic Acid from Aqueous Solution Using Efficient Fenton Type Fe-MCM-41 Mesoporous Materials.
Acid pressure oxidation has been demonstrated to be the only commercially proven process capable of achieving the required level of pyrite oxidation. Gangue mineralization dictates pre concentration of the sulphides to limit the acid consuming capacity and carbon dioxide generation during oxidation.
ALKALINE OXIDATIVE LEACHING OF GOLD-BEARING ARSENOPYRITE ORES By P. Bhakta,1 J. W. Langhans, Jr.,1 and K. P. V. Lei2 ABS"rRACT The U.S. Bureau of Mines developed an alkaline oxidative pretreatment leaching procedure to increase the recovery of gold from arsenopyrite (FeAsS) ores. The best solution compositions for
The refractory ore must be destroyed or attacked by chemical means with the use of oxidative processes, such as oxidation by roasting , pressure oxidation , bio-oxidation …
Ultra Fine Grinding - A Practical Alternative to Oxidative Treatment of Refractory Gold Ores S. Ellis Kalgoorlie Consolidated Gold Mines Kalgoorlie, WA. Abstract Since early 2001, Kalgoorlie Consolidated Gold Mines (KCGM) has successfully operated an ultra fine grinding (UFG) circuit to supplement its roaster capacity for the
However, the rate of heap bio-oxidation of pyrite that encapsulates gold is slow, forcing the mineral industry to seek improved processes for the treatment of refractory gold ores. The indirect oxidation mechanism of pyrite bioleaching has been confirmed by many researchers (Sand et al., 2001, Tributsch, 2001, Heidel and Tichomirowa, 2011 ...
Gold extraction refers to the processes required to extract gold from its ores.This may require a combination of comminution, mineral processing, hydrometallurgical, and pyrometallurgical processes to be performed on the ore.. Gold mining from alluvium ores was once achieved by techniques associated with placer mining such as simple gold panning and sluicing, resulting in direct recovery of ...
Pressure oxidation of pyrite-arsenopyrite refractory gold concentrate 103 Autoclave oxidation tests were conducted in Büchi ecoclave model 075 titanium autoclave. The total volume of the autoclave vessel was about 1.1 dm3 and it was equipped with magnetic agitation unit, gas inlet and outlet, and sampling system with
options for refractory gold ores: roasting; pressure oxidation; bio-oxidation; and ultra-fine grinding. In roasting, pressure oxidation and bio-oxidation, the iron sulphide minerals are oxidised to create sulphur dioxide (SO 2) gas in the case of roasting, or sulphate ions in pressure oxidation and bio-oxidation. The iron component is
The reasons of gold refractory, ore classification, and preprocessing methods. I.The reason of the gold mineral refractory. There are so many types of reasons that caused the difficulty of gold ore processing, including physical element, chemical element, and mineralogical element.
The high-pressure nitric acid oxidation process is shown in Figure 1. LI, D.-X. Developments on the pretreatment of refractory gold minerals by nitric acid. World Gold Conference 2009,The Southern African Institute of Mining and Metallurgy, 2009. Developments in the pretreatment of refractory gold minerals by nitric acid D.-X. LI