Effect of ore dressing on flotation of copper and arsenic minerals in sulphide ore processing

Monomineral flotation results showed that the use of a new reagent S-cyanoethyl N, N-diethyldithiocarbamate enhances the flotation activity of chalcopyrite, in contrast to flotation with butyl xanthate, and reduced the flotation ability of arsenopyrite, which makes this reagent promising for its use in the selective flotation of complex sulfide ores.

Hydrometallurgical Recovery of Cu and Zn from a Complex Sulfide Mineral by Fe3+/H2SO4 Leaching in the Presence of Carbon-Based Materials

Chalcopyrite, the main ore of copper, is refractory in sulfuric media with slow dissolution. The most commonly employed hydrometallurgical process for the oxidation of chalcopyrite and copper extraction is the sulfuric acid ferric sulfate system The main objective of the present work is to study the use of cheap carbon-based materials in the leaching of copper and zinc from a sulfide complex mineral from Iberian Pyrite Belt (IPB). The addition effect of commercial charcoal (VC) and two magnetic biochars (BM and HM) that were obtained by pyrolysis of biomass wastes was compared to that of commercial activated carbon (AC). The experimental results performed in this work have shown that the presence of carbon-based materials significantly influences the kinetics of chalcopyrite leaching in the sulfuric acid ferric sulfate media at 90 °C. The amount of copper and zinc extracted from IPB without the addition of carbon-based material was 63 and 72%, respectively. The highest amount of extracted zinc (>90%) was obtained with the addition of VC and AC in IPB/carbon-based material ratio of 1/0.25 w/w. Moreover, it is possible to recover more than 80% of copper with the addition of VC in a ratio 1/0.25 w/w. Moreover, an optimization of the properties of the carbon-based material for its potential application as catalyst in the leaching of metals from sulfide is necessary.

Bioleaching of Cu and Zn from Complex Sulfide using an Isolated Iron Oxidizing Bacteria

Bioleaching kinetics of copper and zinc from a complex sulfide concentrate sample was evaluated in this manuscript. An acidophilic microorganism was used for the metal dissolution. The metal dissolution was evaluated based on the variation of leaching parameters like initial pH, pulp density, and initial ferrous concentration. The leaching rate of metals increased with the increase of initial ferrous concentration up to 20g/L, and it decreased on a further increase of the initial ferrous concentration. It decreased at the initial ferrous concentration above 20g/L due to the formation of an iron precipitate, which did not allow the contact of lixiviant with the metal sulfide matrix. The leaching rate increased with the increase of initial pH up to 2.0, and thereafter it decreased. Similarly, the leaching rate remained unchanged up to pulp density of 15%(w/v), and it decreased upon further increase of the pulp density due to the mutual completion of the complex sulfide particles towards the lixiviants.

Chalcopyrite leaching in acid media: a review

In the modern practice of copper production, more and more attention is paid to the possibility of treating low-percentage sulfide ores that cannot be treated with conventional procedures (crushing, grinding, flotation). In addition to this, the processes of obtaining copper from complex sulfide concentrates, which cannot undergo pyrometallurgical processing, are increasingly being investigated. Extraction of copper from such raw materials is in most cases achieved by applying leaching procedures. Since chalcopyrite (CuFeS2) is by far the most abundant copper sulfide mineral, a large portion of the research is focused on studying the behavior of chalcopyrite in the leaching process, because processes of copper extraction from increasingly poor raw materials may be created using results of these studies. In addition, the main objective of this research is examining the kinetics and mechanism of chalcopyrite oxidation under the influence of various oxidants (O2, Fe3 +, H2O2, chlorate ions, etc.) and at the same time obtaining data necessary for the development of copper production process that could satisfy increasingly stringent technological, economic and environmental criteria. The paper presents the existing knowledge of the chalcopyrite leaching procedure and phenomena that accompany chalcopyrite oxidation in acidic sulfate and chloride solutions.

Formation of drop-shaped inclusions based on Pt, Pd, Au, Ag, Bi, Sb, Te, As during crystallization of the intermediate solid solution in the Cu-Fe-Ni-S system

The phase and chemical composition of drop-shaped inclusions in directionally crystallized intermediate solid solution was studied. The initial melt contained (in mol.%): Fe 31,79; Cu 15,94; Ni 1,70; S 50,20; Sn 0,05; As 0,04; Pt, Pd, Rh, Ru, Ag, Au, Se, Te, Bi, Sb 0,03. Experimental data indicate the simultaneous crystallization of two types of liquids upon cooling of the initial sulfide melt. One of them is formed in the subsystem (Pd, Au, Ag)-(Bi, Sb, Te), and the second - in the subsystem Cu-(S, Bi, Sb, Te). When these liquids solidified, inclusions formed, which we divided into four classes. Class I has a eutectic-like structure with a matrix of Pd(Bi,Sb)xTe1-x solid solution and Au crystallites with Ag, Cu, and Pd impurities. Class II is formed from sulfosalts with inclusions of Bi and Au. Class III includes inclusions of sperrylite Pt(As,S)2. Class IV forms compound inclusions from fragments of classes I-III. The experiment described in the work showed a more complex behavior of noble metals and metalloid impurities during the crystallization of complex sulfide-metalloid melts compared with the previously described data of isothermal experiments.