In order to recover gold and silver from gold tailings with an efficient and short process, the chlorination roasting method is used [17]. For chlorination roasting, the The results of this study allow to conclude that it is possible to recover gold from alluvial materials by an alternative process such as chlorination, preventing Gold extraction by chlorination using a pyrometallurgical process
Chlorination metallurgy technology mainly includes chlorination, separation, purification, reduction, and refining of the valuable metals in ores, which have Reactions (13–15 and 20–21) with AsCl 3 and ReCl 3 production are thermodynamically more probable than chlorination reactions for gold. Obviously, for a more complete chlorination of gold, it is Sustainability Free Full-Text Chlorination
the high-temperature chlorination of gold were investigated [18–20]. Hager and Hill [21] and James and Hager [22] reported the chlorination behavior of gold at low This paper describes the chlorination roasting-water leaching process for the volatilization separation of gold, zinc and simultaneous vanadium recovery from Cleaner process: Efficacy of chlorine in the recycling of gold
Environmentally Friendly Technology for Separating Gold from Waste Printed Circuit Boards: A Combination of Suspension Electrolysis and a Chlorination Roasting and chlorine leaching of gold-bearing refractory concentrate: Experimental and process analysis. International Journal of Mining Science and Determination of the mechanism of the chlorination of gold
Aqua regia was discovered by the alchemists as a lixiviant for gold and is a mixture of hydrochloric and nitric acids. Chlorine was first used in recovery of gold from its ores in 1851 by Karl Friedrich Plattner, who used metallic iron to cement gold from the chloride leach solution ( Aaron, 1881). The barrel chlorination process used chlorinethe loss of volatile gold chlorides. Chlorination of the bullion has to stop close to 99 fineness to restrict the loss of volatile gold chlorides. The Miller process gases are vented through a milk-of-lime scrubbing system, fol lowed by a filter-bag. In de-golding, the nonvolatile silver and base-metal chlorides (MillerMelting and Refining of Gold Springer
Developed in the mid-19th century, extraction of gold by chlorination was the first hydrometallurgical gold extraction process available on the commercial scale. By passing chlorine gas over crushed ores, soluble gold chloride was produced, which could subsequently be dissolved in water.The direct chlorination of a pure gold was also studied up to a temperature of 1223 K.These experiments demonstrated that the precious metal is not attacked at that temperature, in agreement with the literature, which indicates that the reaction of direct chlorination of gold is produced at high temperatures (Panias and Neou-Syngouna, Gold extraction by chlorination using a pyrometallurgical process
Investigation on the recovery of gold from pretreated cyanide tailings using chlorination leaching process. December 2019; chlorination temperature 333 K and chlorination time 2 h, gold wasFor chlorination roasting, the chlorine gas can penetrate the gold tailings and then react with gold and silver [18], [19]. Many chlorination agents such as CaCl 2, NaCl, FeCl 2, Cl 2, NH 4 Cl, CCl 4 were investigated in the chlorination roasting process [20], [21], [22], [23].Pyrite enhanced chlorination roasting and its efficacy in gold
The chlorination leaching of gold, one of the non-cyanide methods, has the advantages of higher reaction rate, less pollution, simple process, and low cost compared with the cyanide leaching. In this work, the hydro-leaching method consisting of the pressure oxidation pretreatment and chlorination leaching has conducted for the These restrict its development and application in industry. Selective chlorination roasting process has been proved to be more efficient and cheaper for the extraction of the metals, such as Ti, Zr, Nr, Mo, etc. [17]. The chlorination roasting process also can be used to extract gold from the refractory gold ore.The separation of gold and vanadium in carbonaceous gold
The results of the two-stage leaching process of gold from waste mobile phone PCBs in a separate leaching reactor are also presented in ref. . It was demonstrated that, at the first stage of the process, 97% copper and 5% gold are leached into a 2 M HCl solution, and in the second stage, 93% of gold is leached into a 0.1 M HCl solution.The factors and parameters of chlorination process for gold leaching, especially from e-waste, should be studied more deeply and systematically to promote its application. In our previous study (He and Xu, 2015), a less-polluted process of chlorination for selective gold recycling from WPCBs was investigated. The investigation evaluated Integrated technology for recovering Au from waste
An efficient process based on chlorination roasting with CaCl 2 was proposed to recover zinc from copper smelting slag. The reaction mechanism and the kinetics of the chlorination process were investigated by thermodynamic calculation, thermogravimetry and differential scanning calorimetry (TG−DSC) analysis and X-ray Cyanide tailings produced in gold smelting process contain a large number of heavy metals and cyanides, which are more and more harmful to the environment. In order to reduce environmental pollution, valuable metals from cyanide tailings are recovered. The amount of calcium chloride, chlorination time, the way of adding calcium chloride Experiment of Gold and Silver Extraction from Cyanide
In this article, an improved chlorination process, a traditional cyanidation process, and a traditional aqua regia process were quantitatively analyzed and compared from the perspective of environmental impact. The Biwer-Heinzle method is employed. The results showed that the improved chlorination process had the lowest environmental hazard.In the process of recovering gold via chlorination roasting, iron-calcium silicate with a low melting point is generated through a slagging reaction at a melting point of approximately 1373 K (Ma et al., 2018). In its completely molten state, the loose and porous structure of CT is completely destroyed, and gold is wrapped in the slag, whichCleaner process: Efficacy of chlorine in the recycling of gold
This paper describes the chlorination roasting-water leaching process for the volatilization separation of gold, zinc and simultaneous vanadium recovery from carbonaceous gold ore. Chlorination roasting was conducted on carbonaceous gold ore. The chlorination residue and volatile precipitates were examined for textural and chemical The processing of gold scrap varies not only with the gold content but also with the amenability of the gold in the scrap to extraction. Thus, the bulk of the gold may be recovered by leaching techniques using cyanidation or aqueous chlorination, and the residue may then be treated by smelting to recover the balance. Generally, scrap with aGold processing Refining, Smelting, Purifying Britannica
Gold is a highly required material for a wide range of personal and industrial applications. The high demand for gold, together with the shortage of natural resources and high pollution potential of wastes generated during mining and ore processing activities led to search for alternative sources of gold. A possible source is represented Dunn, 1982, Dunn et al., 1991 have extracted gold by chlorination using pyrometallurgical processes at temperatures lower than the ones mentioned above, from refractory minerals and alloys, with a previous roasting process. The objective of this research was, on one hand, to study gold extraction from an alluvial material, through aGold extraction by chlorination using a pyrometallurgical process
Miller chlorination was chosen as the primary refining process as it can produce molten gold of sufficient purity for pouring into saleable bars within 2 h. Wohlwill electrolysis was applied only to deposits with known high Platinum Group Metal content, as these metals are not removed by Miller chlorination, producing gold of 99.99% purity.
