Treatment of a refractory gold—copper sulfide concentrate by copper ammoniacal thiosulfate leaching

Acidophiles have been widely used in heap and dump bioleaching of secondary copper sulfide ores and biooxidation of refractory gold ores. 22 genera of acidophiles have been found in biomining environments. This paper gives a preliminary introduction to the application of mineral biomining in China. Challenges and technical trends for heap bioleaching of primary copper sulfide ores, purification of bioleaching solution of polymetallic sulfide ores and biooxidation of carbonaceous refractory gold ores are also recommended.

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Developing a model of fuzzy logic and a controller to control smelting of copper sulfide concentrate in the Vanyukov furnace

Russian Journal of Non-Ferrous Metals ◽

10.3103/s1067821209020126 ◽

2009 ◽

Vol 50 (2) ◽

pp. 138-141

Author(s):

E. N. Ishmet’ev ◽

I. E. Zykov

Keyword(s):

Fuzzy Logic ◽

Copper Sulfide ◽

Vanyukov Furnace ◽

Sulfide Concentrate

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Biooxidation and Cyanidation for Gold and Silver Recovery from Acid Mine Drainage Generating Tailings (Ticapampa, Peru)

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.20-21.91 ◽

2007 ◽

Vol 20-21 ◽

pp. 91-94 ◽

Cited By ~ 1

Author(s):

Adrian A. Nagy ◽

Eberhard D. Gock ◽

Frank Melcher ◽

Terzan Atmaca ◽

Lothar Hahn ◽

...

Keyword(s):

Acid Mine Drainage ◽

Mine Drainage ◽

Precious Metals ◽

Acidithiobacillus Thiooxidans ◽

Silver Recovery ◽

Acid Mine ◽

Tailings Remediation ◽

Refractory Gold ◽

Shake Flasks ◽

Sulfide Concentrate

The acid mine drainage (AMD) generating sulfidic tailings have a total mass of 1,639,130 t containing 1.65 g/t Au, 34.5 g/t Ag, 7.74 % Fe, 5.91 % S, 3.2 % As, 0.75 % Zn and 0.05 % Cu. The precious metals Au and Ag are enriched in the fine fractions. Approximately 35 % of the material is below 25 /m in size and 53 % below 63 /m. Electron microprobe analysis of a sulfide concentrate of the tailings, produced by gravity separation, proved the occurrence of pyrite and arsenopyrite with appreciable sphalerite and galena. Refractory gold (up to 316 g/t) is hosted in Asrich zones of some arsenopyrites. Approximately 200 g of the sulfide concentrate of the tailings was biooxidized in laboratory shake flasks using an adapted mixed culture of Acidithiobacillus ferrooxidans (Ram 6F), Acidithiobacillus thiooxidans (Ram 8T) and Leptospirillum ferrooxidans (R3). During biooxidation, arsenopyrite was preferentially dissolved and the secondary mineral tooeleite (Fe8(AsO4)6(OH)5·H2O) precipitated. The following cyanidation of the biooxidized sulfide concentrate showed a recovery of 97 % and 50 % for Au and Ag, respectively. The values were 56 % and 18 % for the untreated concentrate. The recovery of Au and Ag from the tailings significantly reduces the costs for the tailings remediation to mitigate AMD release.

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Microwave-enhanced roasting of copper sulfide concentrate in the presence of CaCO3

Separation and Purification Technology ◽

10.1016/j.seppur.2005.11.003 ◽

2006 ◽

Vol 50 (1) ◽

pp. 22-29 ◽

Cited By ~ 21

Author(s):

Yixin Hua ◽

Chaojun Cai ◽

Yan Cui

Keyword(s):

Copper Sulfide ◽

Sulfide Concentrate

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Flotation of Carbonaceous Matter from a Double Refractory Gold Ore: The Effect of MIBC on Flotation Performance and Kinetics

Minerals ◽

10.3390/min11091021 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1021

Author(s):

Sugyeong Lee ◽

Charlotte E. Gibson ◽

Ahmad Ghahreman

Keyword(s):

Bubble Size ◽

Gold Recovery ◽

Carbonaceous Matter ◽

Flotation Kinetics ◽

Pressure Oxidation ◽

Gold Ore ◽

Refractory Gold ◽

Flotation Performance ◽

Thiosulfate Leaching

The use of alkaline pressure oxidation to pretreat refractory gold ore often results in insufficient gold recovery (<60%) in downstream thiosulfate leaching. To improve gold recovery, flotation was considered for the separation of carbonaceous matter (C-matter). In this study, the effect of MIBC on C-matter flotation was investigated to understand the role of the frother in bubble and froth formation and on flotation kinetics. MIBC dosages between 30 and 150 g/t were used in combination with 500 g/t of kerosene as a collector. The results showed that the recovery and selectivity of C-matter were improved with increasing MIBC dosages. Improved selectivity at higher MIBC dosages was attributed to faster C-matter recovery as bubble size decreased to the critical coalescence concentration (CCC) and to changes to the foam structure. Analysis of flotation kinetics showed that the flotation rate increased as the MIBC dosage increased due to the decreasing bubble size and the reduced induction time caused by the interaction between the collector and the frother. The results of this study explain the role of MIBC in C-matter flotation and can be used as a design basis for scavenger-cleaner flotation testing. Overall, the results show the potential for flotation as a means to improve gold recovery in thiosulfate leaching through the removal of C-matter.

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Effect of grain size on the bacterial oxidation of a refractory gold sulfide concentrate and its dissolution by cyanidation

Minerals Engineering ◽

10.1016/j.mineng.2021.107360 ◽

2022 ◽

Vol 176 ◽

pp. 107360

Author(s):

S.H. Andrianandraina ◽

J. Dionne ◽

H. Darvishi-Alamdari ◽

J.F. Blais

Keyword(s):

Grain Size ◽

Bacterial Oxidation ◽

Refractory Gold ◽

Gold Sulfide ◽

Sulfide Concentrate

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Thiosulfate Leaching of Middle-Refractory Gold Ore with Ferricyanide as Oxidant

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.548.309 ◽

2012 ◽

Vol 548 ◽

pp. 309-314

Author(s):

Fu Ting Zi ◽

Xian Zhi Hu ◽

Wen Bin Zhang ◽

Su Qiong He

Keyword(s):

Dissolution Rate ◽

Iron Hydroxide ◽

Pure Gold ◽

Gold Dissolution ◽

Gold Ore ◽

Base Solution ◽

High Dissolution Rate ◽

Refractory Gold ◽

The Stability ◽

Thiosulfate Leaching

In order to decrease the consumption of lixiviant, study on dissolution of pure gold and middle-refractory gold ore using a novel thiosulfate leaching system with ferricyanide as oxidant was carried out. The results showed that the advantage of the novel system is that the thiosulfate consumption is negligible though the potential of ferricyanide is much higher than that of traditional cupric ammine complex. And compared to the ferric oxalate system, novel system could be used at relatively high pH condition which benefit to the stability of thiosulfate because ferricyanide can’t transfer to iron hydroxide in base solution. It is unlikely that very high dissolution rate of gold can be obtained using an air saturated thiosulfate- ferricyanide system without thiourea catalyst. However gold dissolution rate was increased with the increasing of concentration of ferricyanid in 5 mmol/L to 30mmol/L. When 0.1mmol/L thiourea was presented, the dissolution of gold approximately 1.5 times faster than that of in the absence of thiourea. Leaching of middle-refractory gold ore show that both of the consumption of thiosulfate and leaching rate was decreased compare to the traditional copper–ammonia thiosulfate system. Thiourea is not stable in base solution, but it was found that gold dissolution rates can be increased with a little thiourea ,the mechanism is still unclear.

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