PDF) Application of Diagnostic Leaching Technique for
Biooxidation experiments carried out on a refractory Au ore concentrate containing 2.32 % arsenic and 3 1.04 g/t showed that only about 40% of the Au could be recovered from the concentrate by cyanidation without pretreatment and only 46% recovered after roasting and cyanidation, it was possible to recover 76% of the Au after biooxidation and ...
PDF A Fundamental Study of The Acidic Pressure Oxidation of
2.1 Mineralogy of Gold Ores 8 2.2 Behavior of Arsenic and Antimony Sulfide Minerals in Alkaline Cyanide Solution 13 2.3 Pretreatment of Refractory Sulfidic Gold Ores 15 2.3.1 Pressure Oxidation 18 2.4 Acidic Pressure Oxidation of Iron and Arsenic Sulfide Minerals 29 References 38 CHAPTER 3 FUNDAMENTALS OF OXIDATION 45 3.1 Thermodynamics 45
Pretreatments Applied to Refractory Gold Ores | Request PDF
It is necessary to apply a pretreatment to obtain high gold recovery (>80%) from such refractory ores by cyanide leaching. There have been many studies on the oxidation of refractory gold ores for ...
Review Pretreatment Process on Refractory Gold Ores with As
mainly about the refractory gold leaching easily through arsenic removal to expose gold, changing the composition, physic-chemical and electro-chemical properties of the ore. Currently, there are four main methods of pretreatments of refractory gold ores with As. Pretreatment options for deal-ing with refractory gold ores are illustrated in Fig ...
Arsenic Release Through Refractory Gold Ore Processing
Feb 06, 2021 · Arsenic (As) has been well documented as toxic and carcinogenic element since 1970. Mining and extraction of Au, Ag, Pb, Zn, Cu and Ni from sulfides o…
PDF) Mineralogy and Pretreatment of a Refractory Gold
Mineralogy and Pretreatment of a Refractory Gold Deposit in Zambia ... study were obtained from an arsenic-containing sulfur-bearing gold. ... results of mineralogy study, gold partic les had a ...
ACID OXIDATION PRETREATMENT OF REFRACTORY GOLD ORE PRIOR TO
57 Claim 1. A process for recovering gold from refractory auri- ferous iron-containing suiphidic ore comprising: feeding ground ore as an aqueous slurry to an acidic pretreatment step, treating the ground ore in the acidic pretreatment step with aqueous sulphuric acid solution to decompose car- bonate and acid consuming gangue compounds which might other- wise inhibit a subsequent pressure ...
Arsenic – the “Poison of Kings” and the “Saviour of Syphilis
[6, 7, 8] In the early 19th century arsenicals were also developed to successfully treat trypanosomiasis, and currently arsenic trioxide is approved to treat refractory acute promyelocytic leukaemia.  Arsenic is a metalloid element and is widely distributed in the earth’s crust, usually combined with other metals, sulphur or oxygen.
Process of refractory gold mines,gold mines containing
Roasting is a pretreatment method with many years of industrial experimental experience in the industry, especially for removing sulfur and carbon, producing porous calcine material suitable for cyanidation and recovering arsenic. However, the production of gold mines containing arsenic, antimony, mercury, and tellurium is highly successful and ...
Alkaline leaching pretreatment and cyanidation of arsenical
It was also found that pretreatment only in highly alkaline media (pH > 13) can be effective in gold recovery. Gold and silver extractions during subsequent cyanidation were improved from 69.4 to 80.7% for gold and 44.4 to 88.9% for silver, where the extraction yields of arsenic, iron, and zinc were 93.7, 75.9, and 26.9%, respectively.
Pyrometallurgical Recovery of Gold From Refractory Gold
The problem concerning effective processing of gold ledge ores extremely refractory to loosening has been considered. . Among gold ledge ores in Central Kazakhstan, ores from the Sayak-4 gold-arsenic-cobalt deposit discovered in 1950s have not been processed until the present as they are extremely refractory to loosening and beneficiation. [2, 3]. This papers is devoted to experimental ...
Solidification of sulfur and arsenic in gold concentrate and
Jan 19, 2020 · The processing of refractory minerals rich in arsenic and sulfur often causes give off arsenic and sulfur contamination during roasting and oxidation pretreatments. In this paper, the solidification ...
PDF ALTA Gold 2012 E-Doc - Albion Process
The majority of gold ores are classified refractory because the gold mineralogy is contained in sulphides. This type of gold is typically very fine gold or locked in solid solution within sulphide minerals pyrite and arsenopyrite (FeAsS). The arsenic bearing pyrite is commonly known as arsenian pyrite and can contain gold in its structure.
A Study on intensified alkaline leaching pretreatment method
This new pretreatment method is a synthetic physical and chemiscal method .In a tower type grinding and leaching mill,the Yangshu arsenic-containing refractory gold concentrate is ground to 97.38%～33.56μm, then be intensified leaching to 12h by 144kg/t NaOH in a forced agitator tank with the pulp conc. of 40% wt at temperature of 13～15℃ and normal pressure (1atm).The arsenic particles and sulphide particles are selectively oxidation at the oxidation rate of As of 92.1% and 70.2% of S ...
Deposit in Zambia - MDPI
technology of refractory gold deposits [2,3]. The gold mineral should be pretreated before smelting due to the low grade of gold in the ore. The pretreatment process of gold mainly includes gravity separation, ﬂotation, microbial oxidation, etc. [4,5]. Gold occurs usually in its native form or hosts in sulphides (especially pyrite, arsenopyrite,
Implementation of sodium hydroxide pretreatment for
Recent studies demonstrated that sodium hydroxide pretreatment is a viable extractive metallurgy technique for the processing of refractory antimonial gold and silver ores containing zinkenite and ...
Development of a Production Scheme for Processing Rebellious
Jan 25, 2018 · Results are provided for a study of the substance composition of rebellious gold-copper-arsenic concentrate. The nature of gold dissemination in concentrate mineral components is demonstrated and it is established that gold is associated to a considerable extent with iron sulfides, and less with oxides. Based on results of substance analysis, comparative production schemes are proposed for ...
Minerals | Free Full-Text | Specific Refractory Gold
Jan 19, 2021 · The economic significance of gold to the development of several nations (e.g., Australia, South Africa, USA, China, Canada, and Ghana), owing to its coveted qualities and unique applications, can be traced back to the dawn of civilization [1,2,3,4,5,6].In a recent global gold mine reserve estimation , Australia hosts 16% of the world’s total 56,700 t gold worth AUD $ 542.48 billion, at ...
WO2009069005A2 - Microbial pre-treatment of double refractory
The present invention is directed to recovery of gold from refractory and double refractory ores using a fungal agent and/or culture media. The fungal agent is inoculated in the feed material to either decompose sulfide sulfur or deactivate preg robbing carbon The culture media is applied, m the absence of a microbe, to decompose some sulfide sulfur and release a portion of the gold.
Arsenic bioleaching in medical realgar ore and arsenic
from realgar and arsenic-bearing refractory gold ore, respectively. A comparative study on arsenic leaching abilities among different treatments was discussed to investigate the efficiency of mixed cultures of four strains of A. ferrooxidans and A. thiooxidans to bio-oxidize and bioleach two kinds of different arsenic-containing sulfide ores.
PDF) The treatment of arsenic bearing ores, concentrates
As an example, when the alkaline sulfide hydrometallurgical system is applied to a common arsenic containing material like enargite, Cu 3 AsS 4 , which usually contains considerable gold, a ...
PDF) Cyanidation of gold ores containing copper, silver
the kinetics of gold dissolution (Stoychevski and Williams, 1993; Roasting, pressure oxidation, biooxidation, ultraﬁne grinding and Deschenes and Prud home, 1997). modiﬁed cyanidation are the pretreatment methods currently In this study, main cyanidation parameters for two different gold practiced for refractory gold ores and concentrates ...
Improvement of Gold Leaching from a Refractory Gold
A total gold extraction of 70.2% could only be reached via direct cyanidation from a refractory As-, S- and C-bearing gold concentrate calcine, and the gold extraction varied noticeably with different size fractions. The reasons for unsatisfactory gold extraction from the calcine were studied through analyses of chemical composition, chemical phase and SEM-EDS of different sizes of particles.
CN102560138A - Pretreatment method of refractory gold ore
The invention discloses a pretreatment method of refractory gold ore, which is characterized by comprising the following steps of: adopting a dry-wet two-level ball grinder activating and impregnation process; carrying out first-level dry grinding by adopting a vibratory ball grinder and efficiently improving the mineral activity on the basis of energy conservation through adjusting the ...
CN100485059C - Method for recovering gold from sulphide
The invention relates to a method for recovering gold from a sulphidic concentrate, particularly one containing arsenopyrite and/or pyrite, hydro- metallurgically. The concentrate is first subjected to leaching with a concentrated solution of alkali chloride and copper (II) chloride, by means of which the copper minerals and some of the gold in the concentrate are made to dissolve.
Extraction of Gold from a Low-Grade Double Refractory Gold
The treatment process of a low-grade refractory gold ore containing sulfide minerals and carbonaceous matters was studied in this work. The gold extraction of this ore by all-s cyanidation was only 11.75%. Hence, a pretreatment was necessary. In this paper, a flotation-preoxidation-cyanide leaching process was developed.
Developments in the pretreatment of refractory gold
DEVELOPMENTS IN THE PRETREATMENT OF REFRACTORY GOLD MINERALS BY NITRIC ACID 149 Feed material is mixed with water and nitric acid to the desired solids concentration in the feed tank and is fed into the fluidized bed via a positive displacement pump.
Selective arsenic-fixing roast of refractory gold
A novel pretreatment technique suitable for gold extraction from refractory ores was developed. The technique was based on selective arsenic fixing, using a fixing agent in the conventional two-stage roast. As in the existing fixing roast, more than 92 pct of the arsenic was retained in the calcine, using sulfate and lime as selective arsenic-fixing agents in fixing roast process.
Behavior of Arsenic and Aurum Leaching by Roasting Arsenic
Aiming at the difficulties of aurum leaching from arsenic gold ore, the behavior of arsenic and aurum leaching by the roasting pretreatment of arsenic gold ore is discussed. The result indicates as the following: the rate of aurum extraction is only 14.16% to this kind of refractory gold ore by choosing normal method of aurum extraction.
PDF) Bacterial leaching as a pre-treatment step for gold
Fizykochemiczne Problemy Mineralurgii, 32 (1998), 173–181 Alper ÖZKAN*, Salih AYDOGAN*, Ünal AKDEMIR* BACTERIAL LEACHING AS A PRE-TREATMENT STEP FOR GOLD RECOVERY FROM REFRACTORY ORES In this article, pre-treatment such as bio-leaching before cyanidation is discussed as an alternative technique to treat refractory gold ores containing pyrite and arsenopyrite.
Mineralogy and Pretreatment of a Refractory Gold Deposit in
According to the results of process mineralogy, the reasons for the low efficiency of beneficiation and the possibility of removing arsenic from gold concentrate are analyzed, and a suitable pretreatment process is proposed to recover the refractory gold ore reasonably and efficiently. Table 1. Chemical analysis of the raw ore (mass fraction, %).
Studies on the bioleaching of refractory concentrates
Studies on the bioleaching of refractory gold concentrates substrate, and that the bioleaching of pyrite occurs via a multiple sub-process mechanism. Therefore, for the case of pyrite bioleaching the primary role of the bacteria is the oxidation of the ferrous-iron to the ferric form, thereby maintaining a high redox potential within the system and
BMC Biotechnology BioMed Central
group used a domestic strain of At. ferrooxidans and a gold refractory mineral to study the influence of a magnetic field, surfactant addition and the presence of Ag+, Bi3+, Co 2+ y Hg ions over the bioleaching process . They found a reduction to 120 hours to leachate 60% of arsenic using magnetized water and the addition of tween-80 sur-
Ozone: Science & Engineering Pretreatment with Ozone for
of effluents containing cyanide (Mathieu, 1977; Rowley and Otto, 1980), and on the oxidative leaching of copper ores (Roca et al., 2000). In this research work the use of ozone is proposed as oxidative pretreatment for gold and silver refractory ores with the aim of modifying the pyritic matrix and thus exposing the precious metals to cyanide.
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 investigated. Au recovery was increased from 79.4% to 89.4% in the presence ...
One Novel two-step Bio-Oxidation Pretreatment of Arsenic
oxidation process of arsenic-pyrite refractory gold material prior to cyanidation [21, 23]. To date, there are few reports on bio-oxidation pretreatment regarding arsenic-containing concentrate. Therefore, in this work, the pretreatment of one high arsenic gold-bearing concentrate by the two-step bio-oxidation
PRESSURE OXIDATION OF REFRACTORY GOLD ORES: THE
Chesapeake Gold Corp. is currently studying the development of its Metates Gold project in the state of Durango, about 175 km north of the city of Mazatlan, in Mexico. A preliminary feasibility study has been concluded to date. The overall flow sheet that has been considered comprises. of . …
Reduction of arsenic content in a complex galena concentrate
Oct 13, 2004 · Background Bioleaching is a process that has been used in the past in mineral pretreatment of refractory sulfides, mainly in the gold, copper and uranium benefit. This technology has been proved to be cheaper, more efficient and environmentally friendly than roasting and high pressure moisture heating processes. So far the most studied microorganism in bioleaching is Acidithiobacillus ...
Study on dearsenification of gold concentrate by microwave
Tong linlin, jiang maofa, Yang hongying, et al. Experimental study on the extraction of gold from a refractory gold concentrate with high arsenic content by bacterial oxidation and cyanidation [J]. Precious metals,2008,32(1):15-18. (in Chinese)  Nanthakumar b. myicrowave pretreatment of a double refractory gold ore[J]. Minerals Engineering ...
Optimizing the alkaline oxidation pretreatment of a
Sep 28, 2018 · This study investigates the alkaline oxidation pretreatment process of Zarshuran refractory gold ore. Taguchi method-orthogonal array design (OAD) is applied to evaluate and optimize the influence of five main factors including solution pH, …