Selective impurity removal and Cu upgrading of copper flotation concentrate by a spontaneously oxidative H2SO4 leaching process

Nickel bioleaching from copper flotation concentrate assumes greater significance because of its value and not many studies are carried out in these lines. Hence, nickel leaching was attempted and several process parameters of bacterial oxidation for copper flotation concentrate were examined for optimization. The parameters considered for shake flask leaching experiments were temperature, pulp density, particle size, agitation, residence time and inoculum size. The effect of variable proportions of each parameter on nickel leachability was studied. Optimum values of pulp density (10%) and agitation (140 rpm) played an important role in controlling the mass transfer resistance during leaching process. Increase in temperature from 27oC to 30oC has accelerated the bacterial oxidation process while initial concentration of inoculum (1-10%) has not shown considerable variation in nickel leachability. A particle size of ±60#size was found to be essential for bacterial attack. Maintenance of optimum conditions of leaching has yielded considerable nickel recovery (55%) compared to low recovery under unoptimal conditions.

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Recovering Gold from a Gold-Bearing Pyrite by Flotation and Chemical Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.610-613.81 ◽

2012 ◽

Vol 610-613 ◽

pp. 81-85

Author(s):

Qing Li ◽

Bao Liang Ge ◽

Jie Liu ◽

Chao Zhu

Keyword(s):

Chemical Process ◽

Adsorption Rate ◽

Leaching Rate ◽

Cyanide Leaching ◽

Gold Leaching ◽

Flotation Concentrate ◽

Leaching Process ◽

Roasting Process ◽

Gold Bearing

The ore assays 2.5g/t Au, 23.4% S and 56.6% Fe. This research enriched the gold by flotation, and recovered it by a chemical process. The obtained flotation concentrate contains 66.35%g/t gold and 37.06% S with recovery 96.14% and 96.42% respectively. A roasting process was conducted at 900-1000°C for 5.5hrs, followed by cyanide leaching of the residue. The gold leaching rate reaches 87.4% with an adsorption rate of 97.6%. Furthermore, the regrinding of the concentrate to 95% -0.18μm was conducted, and followed by cyanide leaching at pH11.5 for 12hrs. The results show the amount leached gold reaches 92.5% with an adsorption rate of 99.21%, which increases by 1.61% and 5.1% in comparison with the roasting-leaching process.

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5110455 Method for achieving enhanced copper flotation concentrate grade by oxidation and flotation

Minerals Engineering ◽

10.1016/0892-6875(93)90147-f ◽

1993 ◽

Vol 6 (2) ◽

pp. 232

Keyword(s):

Flotation Concentrate ◽

Concentrate Grade ◽

Copper Flotation

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Biooxidation Pretreatment Cyanide Leaching of a Flotation Gold Concentrate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.581-582.1106 ◽

2012 ◽

Vol 581-582 ◽

pp. 1106-1109

Author(s):

Chao Zhu ◽

Bao Liang Ge ◽

Zhao Yi Lu ◽

Wen Zhu

Keyword(s):

Leaching Test ◽

Leaching Rate ◽

Cyanide Leaching ◽

Gold Leaching ◽

Flotation Concentrate ◽

Gold Ore ◽

Leaching Process ◽

Direct Leaching

This study reached a gold ore which contain 3.83g/t gold, to investigate the available gold recover methods, direct cyanide leaching test and “biooxidation-cyanide” leaching process were utilized after enrich gold by flotation. When regrinding the flotation concentrate to 95% -325mm, the leaching rate of “biooxidation-cyanide” leaching reached 94.47%, compare with direct leaching, the leaching rate increased almost 67%. Obviously bacterium oxidation is a useful pretreatment for gold leaching.

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