Microwave Pyrolysis Pretreatment of High Arsenic Refractory Gold …
The process optimization and mechanism of microwave pyrolysis in a nitrogen atmosphere were studied to improve the gold leaching rate for high-arsenic-refractory gold sulfide resources, mainly containing minerals of elemental sulfur, dense pyrite, and arsenopyrite. The decomposability was evaluated using thermodynamic and …
Pore Evolution in Refractory Gold Ore Formed by …
stirring was continued for 30 min. Gold leaching lasted 24.0 h with a concentration of 0.3% NaCN. The leaching residue was filtered and dried before measuring the gold grade. The leaching rate of gold (η) is calculated as follows29,36 η 1 θ β =− × i k jj jj y {zz zz (2) where η is the leaching rate of gold, β is the gold grade of
Cyanidation of Refractory Gold Ores: A Review
The depletion of readily amenable gold ores and discovery of complex dep osits inspire. knowledge improvement and search of commercially effective te chnique in extracting gold from refractory ...
A novel process for silver recovery from a refractory Au–Ag ore …
For the refractory gold–silver ores associated with manganese minerals, this study has developed a reductive sulfating leaching pretreatment process to dissolve manganese minerals before gold–silver cyanidation, and pyrite has been proved that could be used as an effective reductant in the pretreatment step.
Pressure Oxidation Pretreatment of Refractory Gold
Pressure oxidation of gold containing concentrates and ores is an effective pretreatment for liberating refractory gold. This is particularly true when an appreciable portion of the gold is associated with sulfides and is not amenable to conventional cyanidation. A brief review of the literature on pressure oxidation of refractory gold materials is presented. …
Treatment of carbonaceous refractory gold ores
In addition the paper describes the various pre-cyanidation treatment methods for carbonaceous refractory gold ores namely, (1) flotation and depression, (2) blanking, (3) the use of activated carbon or resin in leach, (4) roasting, (5) chemical oxidation and (6) bioleaching. Previous. Next.
(PDF) A Pretreatment of Refractory Gold Ores Containing …
The effects of HAsBS ore on gold leaching in ammonium thiosulfate solutions were investigated, and it was found that gold extraction in the presence of HAsBS ore was suppressed because of the ...
A review on the negative impact of different elements during
Semantic Scholar extracted view of "A review on the negative impact of different elements during cyanidation of gold and silver from refractory ores and strategies to optimize the leaching process" by G. Larrabure et al. ... Oxidation of sulfide mineral and metal extraction analysis in the microwave-assisted roasting pretreatment of refractory ...
Pretreatment with Ozone for Gold and Silver Recovery from Refractory Ores
The pretreatment of gold ores before cyanidation is a challenging problem due to the world's annual huge waste of refractory gold minerals. Generally, the leaching of gold by cyanidation without ...
Pretreatment of refractory gold minerals by ozonation …
The problems during the leaching of gold show the necessity for ore pretreatment to minimize the gold entrapment with refractory minerals and solve the …
A review on the negative impact of different elements during
The ongoing depletion of gold and silver-containing ore deposits demands a shift towards the processing of more complex sources. Leaching of gold or silver from these sources, which are named ...
Optimization of the synergy between reduction leaching of …
A new process for extracting gold from refractory gold ore and manganese from manganese anode slime was developed by combining the oxidative pretreatment of refractory gold ore and reductive leaching of manganese anode slime. The response surface methodology was used to optimize the effects of time, temperature, and sulfuric …
Recovery of gold from sulfide refractory gold ore: Oxidation …
Following pretreatment, refractory gold ores are leached in order to extract gold. Currently, the leaching agents are separated into two groups: cyanide and non …
Optimization Process of the Refractory Gold Ore Extraction …
Hypochlorite leaching system is a strong oxidizing solution for metal sulfides, which are naturally associated with gold extraction. This study evaluated the hypochlorite leaching of refractory gold ore by using the response surface method–central composite design (RSM-CCD) as a statistical approach in determining the optimum condition of …
Pretreatment Process on Refractory Gold Ores with As
... As a refractory gold ore, a large proportion of finely disseminated gold is encapsulated in the sulfide matrix of arsenopyrite, resulting in inefficient gold recovery …
Effect of Oxidative Pretreatment and Lead Nitrate Addition …
Cyanidation is the main process in gold leaching. There are several parameters that affect gold recovery and cyanide consumption. In this paper, the effect of the oxidative pretreatment and lead nitrate addition on the cyanidation of Zarshuran refractory gold ore containing 3.32 ppm Au, 1.09% As, and 0.5% sulfur were …
(PDF) Thermodynamic Behavior of Pyrite and Arsenopyrite
the refractory gold ore and is the accomplished process, and the operation is simple, but the gold leaching rate is not high and the cost of waste gas treatment is expensive [12, 13].
Process mineralogy characteristics of acid leaching
In order to achieve efficient gold recovery from the refractory gold ores, an effective pretreatment process of refractory gold ore has become a necessity [19][20][21]. ...
Pretreatment Process on Refractory Gold Ores with As
Abstract. The problem of the refractory nature of gold bearing arsenide ores is described. The basic principle, characteristics and application of pretreatment technique of arsenic …
Heap Leaching of Gold-Bearing Deposits: Theory and
CHAPTER 5. Heap Leaching of Gold-Bearing Deposits: Theory and Operational Description. James A. Brierley. Introduction. Biooxidation. pretreatment of refractory …
Oxidative pretreatment of refractory gold ore using …
The maximum leaching efficiency of gold reached 86.9% after ultrasonic activated persulfate pretreatment for 3 h. This study provides a promising refractory gold ore pretreatment to improve gold leaching through persulfate oxidation using …
Optimization of˜the˜synergy between˜reduction …
Li et˛al. 2006)efore, such a gold ore is regarded as refractory. With the depletion of free-milling gold resources, the utilization of˛refractory gold ore is imminent. The treat-ment process of refractory gold deposits can be divided into pretreatment and gold extraction. The pretreatment process
Process mineralogy characteristics of acid leaching residue …
To provide a theoretical basis for a suitable process to extract gold from refractory gold concentrates, process mineralogy on the acid leaching residue of gold calcine was studied by chemical composition, X-ray diffraction, scanning electron microscopy-energy spectrum, and mineral dissociation analysis. The results showed …
Diagnostic pre-treatment procedure for simultaneous cyanide leaching …
In this study, the extraction of gold from a copper-bearing gold ore by ammoniacal cyanide leaching was studied. Furthermore, ammonia leaching as a pretreatment process ahead of cyanide leaching was also examined. Only ~12% of gold was extracted by direct cyanide leaching of the ore. The addition of lead nitrate did not affect the leaching of …
Diagnostic pre-treatment procedure for simultaneous cyanide leaching …
Sulfide gold ores account for a large proportion of refractory gold ores, therefore, it is very meaningful to recover gold from sulfide gold ores (Ubaldini and Vegliò, 2000; Saba, 2011; Hammerschmidt, 2016). Moreover, the major gold leaching process for extracting gold from ores and concentrates is still cyanide leaching.
Mechanism of synergistic pretreatment with ultrasound and …
It has been reported that the pretreatment method has a significant effect on the leaching percentage of the refractory gold ore. The leaching results of the refractory gold ore under different pretreating processes are shown in Fig. 3. The leaching percentages of Au and Ag are 49.12% and 4.01% respectively when gold ore is directly …
Refractory gold ores: Challenges and …
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 …
Pretreatment of refractory gold ore by curing with …
This indicated a significant transformation in the composition of the gold ore, and also suggested that the concentrated sulfuric acid pretreatment and curing residue …
Research status of carbonaceous matter in carbonaceous gold ores …
Gold is mainly present in the form of [Au(CN)2]− during the cyanide leaching process, and this [Au(CN)2]− can be adsorbed by graphite in carbonaceous gold ore resulting in preg-robbing gold.
Oxidative pretreatment of refractory gold ore using …
The pretreatment of refractory gold ore is a complex chemical process. In addition to the oxidation of pyrite, some side reactions also occur. The phase changes of refractory gold ore before and after pretreatment are shown in Fig. 11. The main phases of refractory gold ore include quartz (SiO 2), pyrite (FeS 2), and dolomite (CaMg(CO …