Ore Have To Be Oxidised Before Leaching

Investigation into the mineralogy and flotation performance of oxidised

Investigation into the mineralogy and flotation performance of oxidised PGM ore Megan Becker a, ⇑, Jenny Wiese a, Mpho Ramonotsi b a Centre for Minerals Research, University of Cape Town, Rondebosch, South Africa b Pilanesberg Platinum Mines, Centurion, South Africa article info Article history: Received 21 February 2014 Accepted …

Agitation and column leaching studies of oxidised copper …

The efficiency of reductive leaching of oxidised copper-cobalt ore with sulphuric acid is highly dependent on pH (≈1.5). The pH can be maintained by the addition of make-up acid. Moreover, the amount of reducing agent used to reduce Co ... Before the ore sample was loaded, a screen was placed at the bottom of the columns to allow only …

Oxidation Roasting of Fine-Grained Carbonaceous Gold Ore…

During the past 30 years, many scholars have studied the leaching of pretreated gold ore in detail and formed a systematic theory and design scheme [9,10,11,12]. However, most of the research objects were sulfide minerals and gossan-type gold deposits. ... Before the test, the samples were vacuum pretreated at 150 °C for 3 h, …

A New Technique for Recovering Copper From Complex Copper Oxide Ore …

Copper oxide ore has a complex composition, and a low recovery rate is often achieved via the traditional sorting method. A new combined process of flotation–high-gradient magnetic separation–leaching is proposed here to recover copper minerals. The test results showed that the flotation process was successful when using sodium sulfide …

Pretreatment of refractory gold ore by curing with …

3.1 Pretreatment by sulfuric acid curing 3.1.1 Effect of temperature. Weight loss rate and iron removal rate of ore samples at different reaction temperatures are shown in Fig. 1.The reaction time was set to 3 h, the liquid–solid ratio was 3:1, and the mechanical stirring speed during leaching was 400 r/min for adequate mass and heat transfer.

Recovery of gold from sulfide refractory gold ore: Oxidation …

Typically, gold is encapsulated or finely disseminated in refractory gold ores and the direct cyanidation is not effective for gold extraction from these ores, even after the ore is ground to exceeding small particles (Nazari, 2017, Corrans and Angove, 1991).Especially for sulfide refractory gold ores, in order to recover gold, many oxidation …

Pore Evolution in Refractory Gold Ore Formed by Oxidation …

Refractory gold ore is usually affected by the associated carbonaceous matter through the preg-robbing effect, which is eliminated by oxidation roasting, followed by leaching, to achieve a satisfactory gold leaching efficiency. Roasting–leaching experiments, pore structure measurements, scanning electron microscopy (SEM), and X …

Pore Evolution in Refractory Gold Ore Formed by Oxidation …

The leaching residue was filtered and dried before measuring the gold grade. The leaching rate of gold (η) is calculated as follows 29,36. 2. where η is the leaching rate of gold, β is the gold grade of calcinate, and θ is the gold grade of the leaching residue. ... Xie F. Research on leaching of carbonaceous gold ore with …

Recovery of PGMs from an oxide ore by flotation and leaching

The best leaching results of 48% Pt and 24.5% Pd were obtained using aqua regia solution though it is non-selective. Leaching of ROM ore is generally not preferable as it leads to high reagent consumptions. In this study it was postulated that leaching of low grade flotation concentrate would be preferred.

An efficient process to upgrade siderite ore by pre oxidation

The chemical compositions of iron concentrates before and after leaching process are listed in Table 3. It can be observed that the contents of magnesium and calcium in iron concentrate declined after acid leaching, with the result that iron grade increased from 59.57% to 62.01%. ... The pre-oxidation of siderite ore before the …

Oxidised Pyrite Leaching by Potassium Cyanide

When the pyrites occur in tailings which have been subjected to the action of the weather for some time before treatment, compounds are formed which are more prejudicial to the solution than the sulphides. Sulphide of iron, FeS2, is oxidised by air and water, ferrous sulphate and free sulphuric acid being formed, thus: FeS2 + ... [#]

An investigation into the leaching behaviour of copper …

The dissolution of carbonate gangue minerals, which are often ubiquitous in copper deposits, leads to the consumption of large amounts of acid during the leaching of such ores, which can make the process uneconomical (Habashi, 1970, Habashi, 1980, You-Cai et al., 2013).Table 1 shows the acid consumption and estimated time to complete …

Leaching behaviour of mechano-chemically activated bio-oxidised …

In this paper, the leaching behaviour of mechano-chemically activated, refractory, bio-oxidised flotation gold concentrates has been investigated. In particular, the effect of activation parameters (e.g., milling time and speed, and ball to pulp ratio) and cognate physico-chemical changes on the impact of the refractory mineral components …

Gold leaching from oxide ores in alkaline glycine solutions in the

2.2. Sample preparation. Four gold oxide ore samples were ground to passing 75 μm. The mineralogical composition of the samples was determined by Quantitative X-ray Diffraction (Q-XRD).To calculate the final gold extraction, the feed and final leach residues were analysed for gold by fire assay and for base metals and other …

Leaching behaviour of mechano-chemically activated bio-oxidised …

Complementing ore bio-oxidation with mechano-chemical activation for improved gold extraction. ... The minimum degree of increase in the surface area of the as-received bio-oxidised product, before cyanide leaching, was 1.4 times whilst the maximum degree of increase was 3.8 times. It was evident that increasing the …

Preparation of Industrial Sodium Chromate Compound from …

As seen from Fig. 2a, b, the morphology of the residue derived from the oxidation of chromite is totally different from that of the ore before leaching and present a rough and porous surface. This apparently showed that the chromite can be oxidised and dissolved by water while roasting with Na 2 CO 3.

16.6A: Microbial Ore Leaching

Microbial ore leaching (bioleaching) is the process of extracting metals from ores with the use of microorganisms. This method is used to recover many different …