The carbonaceous ore showed only 20% gold extraction, since gold–iodide complexes readily adsorb on organic matter. In contrast, gold extraction from the oxide …

The roasting of a refractory gold concentrate using microwave radiation has been investigated. The TGA results in air show that there was a continuous mass loss from room temperature to 1000 °C with a total mass loss of 23%. The major mass loss of over 10% occurred between 400 °C and 600 °C and this was attributed to the oxidation of …

Refractory gold reserves, which require more sophisticated treatment methods in order to achieve oxide-ore recovery rates, correspond to 24 percent of current gold reserves and 22 percent of gold resources worldwide (Exhibit 1). ... second, to eliminate carbonaceous material occurring in the ore, which adsorbs dissolved gold …

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 …

The generated thiosulfate from sulfide gold ore can still be applied to leaching oxide gold ore, gold calcine and other exposed gold-bearing raw materials. ... Biological pretreatment of carbonaceous matter in double refractory gold ores: a review and some future considerations. Hydrometallurgy, 196 (2020) Google Scholar. …

The oxidation roasting of carbon-bearing micro-fine gold can eliminate or weaken the robbing effect of carbonaceous materials and clay, and destroy the encapsulation of micro-fine gold. The micropores produced by gas escaping during the roasting process are conducive to the diffusion of leaching agents, thus enhancing the …

An oxide gold ore was subjected to chloride/hypochlorite leaching at room temperature. The effects of three factors, including Ca (OCl)2 vs. NaOCl, OCl− concentration, and HCl concentration on ...

For carbonaceous gold concentrate or carbonaceous pressure-oxidized gold ore, the gold leaching efficiency by cyanide is relatively low (J. Wang et al., 2019). This is due to the presence of abundant and structurally complex carbonaceous matters in gold ores, which can adsorb gold complexes and trigger "preg-robbing" effect, resulting …

In this work, a novel acetylcholinesterase biosensor, namely, gold nanocages/graphene oxide–chitosan nanocomposite modified screen-printed carbon electrode was prepared for chlorpyrifos detection. ... A novel covalently modified graphene oxide has been synthesised and demonstrated as a carbonaceous chemosensor for …

DOI: 10.1016/j.hydromet.2019.105204 Corpus ID: 209719015; Eco-friendly leaching of gold from a carbonaceous gold concentrate in copper-citrate-thiosulfate solutions @article{Wang2020EcofriendlyLO, title={Eco-friendly leaching of gold from a carbonaceous gold concentrate in copper-citrate-thiosulfate solutions}, author={Jian …

Abstract. Oxidation roasting is one of the most effective methods to remove carbonaceous matter from carbonaceous gold ore. However, the consolidation of …

Carbonaceous gold ore obtained from the Prestea Goldfield, Ghana, was fractionated into its organic components by means of NaOH leaching, benzene treatment, and hydrofluoric acid leaching. ... for gold concentration 222 TABLE 1 Chemical analysis of the Prestea carbonaceous gold ore and extracts derived from it Oxide/Element …

Abstract. Carbonaceous materials with nanoframeworks are vital for advanced nanotechnologies and devices in the area of sustainable energy. Various carbonaceous materials have been explored as main electrode composites, efficient adsorbents, and for hydrogen storage. Because atomic boron is an electron deficient element, the boronated …

Gold ores containing carbonaceous matter and sulphidic minerals are generally referred to as double refractory. Extraction of the gold from such ores usually requires an oxidation step to both liberate the ultra-fine gold from the matrix of the sulphides and remove the carbon that preg-robs the dissolved gold.

Carbonaceous coatings are beneficial for the reduction of oxygen and gold, and lead to enhanced preg-robbing of pyrite (Tan et al., 2006a). The kinetics of gold leaching from a non-carbonaceous sulfide ore is retarded if the ore is ground with carbonaceous matter, but mixing the two after grinding has little effect (Tan et al., 2005a).

The literature contains various information in processing complex gold-copper ores. For instance, the classification of complex gold ores into cyanide-consuming minerals, oxygen-consuming minerals, and preg-robbing materials was provided by the previous investigators [16, 17].The solubility of copper minerals in cyanide solution …

But gold has some unexpected properties, too. For instance, gold nanoparticles can be used as a catalyst to oxidize carbon monoxide (CO) into carbon …

ABSTRACT: Refractory gold ore is usually affected by the associated carbonaceous matter through the preg-robbing effect, which is eliminated by oxidation roasting, …

Sample Preparation. To significantly reflect the promoting effect of iron oxide on the combustion of carbonaceous materials in mold flux, a mold flux product with high carbon content was selected as the raw sample, and its main chemical composition is shown in Table I (Corresponding information is given by the mold flux producer). The …

Contributions of distinct gold species to catalytic reactivity for carbon monoxide oxidation | Nature Communications. Article. Open access. Published: 16 …

A carbonaceous gold concentrate containing a high content of dolomite was provided by the Shandong Gold Co. of China. The concentrate has a particle size of 89.5% passing 38 μm. ... Ammoniacal thiosulfate leaching of refractory oxide gold ore. International Journal of Mineral Processing, Volume 164, 2017, pp. 6-10. Esmaeil …

Ores in which gold is associated with sulfides and with high carbonaceous matter content are considered double refractory. The northern Nevada region in the United States is a main area where this type of ore is found. Ores in the Carlin Trend District are characterized by the presence of submicroscopic gold (invisible gold) finely …

carbonaceous gold ores on the degree of maturity of the resident carbonaceous materials. Keywords: Carbonaceous materials, Preg-robbing, Oxide ore, Auro-cyanide 1 Introduction Gold from prehistoric times has been considered a very precious metal and the medieval alchemist considers gold as a metal of perfection (Adams, 2005).

The leaching behavior of gold from an oxide gold ore using copper–tartrate–thiosulfate solutions has been investigated. Experimental parameters, including temperature, initial pH, and concentrations of copper tartrate and thiosulfate, …

A series of metal oxides hollow spheres (Cr2O3, α-Fe2O3, Co3O4, NiO and ZnO) have been fabricated using the glucose derived-carbonaceous spheres as sacial templates and the metal chlorides ...

Graphene oxide (GO) is a graphene sheet decorated with abun-dant oxygen-containing functional groups, such as hydroxyl groups (-OH) and carboxyl groups (-COOH) [16]. However, the conductivity of GO is less due to many defects that exist in its structure. Chemical reduction can restore the conductivity of GO by removal of oxygen.

A carbonaceous gold concentrate containing a high content of dolomite was provided by the Shandong Gold Co. of China. The concentrate has a particle size of 89.5% passing 38 μm. ... Ammoniacal thiosulfate leaching of refractory oxide gold ore. Int. J. Miner. Process., 164 (2017), pp. 6-10. View PDF View article View in Scopus Google …

Oxidation roasting is one of the most effective methods to remove carbonaceous matter from carbonaceous gold ore. However, the consolidation of calcine is a common problem caused by a large amount of heat release during the oxidation roasting of gold ore with high carbon and sulfur content. In this study, a two-stage …

Preparation of gold nanoparticles (AuNPs) and AuNP-modified carbonaceous disk electrodes. 250 µL of tetrachloroauric (III) acid (25 mM, HAuCl 4.3H 2 O) solution was first diluted to 50 mL, and 5 mL of 1.5% trisodium citrate solution was slowly added under 500 rpm vigorous stirring at 98 °C. Upon color change to wine red, the …

Carbonaceous gold ore contains a large amount of carbon, organic carbon and carbonate. During the gold extracting process, the dissolved gold complex will be adsorbed by carbonaceous matter, thus causing low gold extracting efficiency. ... Reductive leaching of manganese oxide ores using waste tea as reductant in sulfuric …