Refractory Gold Ores Research Articles

Chemical oxidation of arsenopyrite by strong oxidizing agents: For oxidative pretreatment of refractory arsenopyritic gold ores

Chemical oxidation of arsenopyrite by strong oxidizing agents: For oxidative pretreatment of refractory arsenopyritic gold ores

Defining the applicable pathway of laccase pre-treatment in the bio-mineral processing of double refractory gold ores based on carbonaceous matter characterization

Enzymes application in mineral processing is a novel alternative to oxidize carbonaceous matter in double refractory gold ores (DRGOs) and reduce Au(CN)2- adsorption during cyanidation. In this work, contrasting flotation concentrates from DRGOs with different Au(CN)2- affinities were sequentially treated to improve Au cyanidation. Sequential pre-treatment comprised sulfide decomposition and carbonaceous matter degradation through laccase-mediator system (LMS). In addition, carbonaceous matter was characterized from various aspects using Raman spectroscopy, 3D-fluorescence spectrometry, preg-robbing test, and gas chromatography-mass spectrometry (GC-MS). The characterization of the original ores showed that Au(CN)2- adsorption densities were positively correlated with the relative intensities of defective carbon to graphitic carbon obtained in Raman spectra. Degradation of carbonaceous matter through LMS was inhibited by the presence of biopolymers formed during extensive bio-oxidation, thus reconsidering the appropriate sulfide decomposition step. When FeCl3 leaching to decompose sulfides proceeded enzymatic treatment, mass spectra of extracted intermediates from carbonaceous matter suggest the presence of alcohols, fatty acids and aliphatic hydrocarbon moieties, mainly on the most polar solvent fractions. This suggests that enzymatic degradation went through the indirect disturbance of the aromatic planes, making the surface more hydrophilic due to the inclusion of oxygen-containing functional groups, thus improving Au extraction. Finally, the current findings provide a general panorama for selecting the appropriate pre-treatments to maximize gold extraction on DRGOs when using LMS.

Kinetics of regeneration of oxidative Cu(II) and Fe(III) species in aerated acid chloride leaching solutions at 75 °C

In the leaching of copper sulfide ores or refractory gold ores in chloride solutions, the regeneration of oxidative agents such as Cu (II) and Fe (III) is a key aspect for a sustainable process over time. This regeneration is carried out from the oxidation of Cu (I) and Fe (II) with O2, which helps to maintain a conveniently high oxidative potential in solution and a high leaching efficiency. In this context, Cu (I) and Fe (II) oxidation are affected by the accumulation of Cu or Fe species resulting from sulfide dissolution during the process. Therefore, a good understanding of the interaction mechanism of O2 with Cu (I), Cu (II), Fe (II), and Fe (III) species is necessary to describe the oxidation kinetics in this complex environment. The present work reports a study of the Cu (I) and Fe (II) oxidation at 75 °C in solutions containing 4.0 M NaCl and 0.1 M HCl. The solutions used in the experiments contained different initial concentrations of Cu (I), Cu (II), Fe (II), and Fe (III) with values in the range of 0.0001 – 0.1 M. Experiments were conducted in a thermostatized reactor containing 0.5 L solution agitated with a magnetic stirrer at 450 rpm, while oxygenated by air bubbling at 3.5 L/min. The evolution of the concentration of Cu (I), Cu (II), Fe (II), and Fe (III) during oxidation was determined by an electrochemical method, which was mainly based on Eh measurements of solution over time. A reaction mechanism was proposed for the oxidation of Cu (I) and Fe (II) with O2 in the presence of Cu and Fe species, which described very well the results obtained in the oxidation experiments under various conditions. Based on the proposed mechanism, a kinetic model was developed that could predict the concentration of Fe (II), Fe (III), Cu (I), Cu (II), O2, HO2–, H2O2, OH– and H+ in acid aerated chloride solutions satisfactorily. These proved to be a valuable tool to approach the modeling of chloride-leaching reactors.

Removal of Impurities from Refractory Gold Ore using Bio-reduction and Bio-oxidation processes

Gold in refractory gold ore is difficult to be extracted by conventional metallurgical method due to the presence of sulfide minerals with elevated levels of iron (Fe), sulfur (S), and arsenic (As) as impurities, resulting in low gold (Au) recovery. Conventional methods such as cyanide leaching has been proven ineffective for gold extraction from refractory ore due to gold being intricately bound within the sulfide minerals. Consequently, this study explores the application of bioleaching as an alternative to conventional cyanide leaching. Shewanella oneidensis (S. oneidensis) and Acidithiobacillus ferroxidans (A. ferroxidans) serve as bio-reduction and bio-oxidation agents, respectively in the bioleaching process. The composition of minerals in the ore was determined through XRD analysis (Model: Rigaku’s Miniflex 600) and EDX analysis (Model EDX 3). Meanwhile, SEM analysis (Zeiss EVO LS15 SEM) was utilized to examine the morphology structure. The concentrations of impurities (Fe, S, and As) were assessed using a spectrophotometer (Model: DR3900 Hach) meanwhile the Au concentration was determined through ICP-OES (Model: G8015A5110 ICP-OES). Sieved refractory gold ore samples with less than 32 um and varying in weight (0.5 g, 1.0 g, 1.5 g, 2.0 g), underwent bio-reduction and bio-oxidation processes. The results indicated a rougher surface morphology of raw sample as observed through SEM analysis. Furthermore, XRD and EDX results demonstrated a decrease in impurity concentrations, suggesting a potential increase in gold purity. Notably, the bio-reduction process exhibited a superior enhancement in Au concentration with the values of 138.89% compared to biooxidation with the value 122.22%. Thus, the bio-reduction process proved more effective in increasing Au concentration compared to bio-oxidation.

Atomic-level into the microscopic mechanism of gold capture by FeS during gold collection in matte process

Understanding the microscopic mechanisms involved in gold capture by FeS at the atomic level is crucial for optimizing the matte process and improving the gold recovery from gold concentrate containing arsenic and antimony. Herein, the DFT method was employed to explore the adsorption structure and electronic characteristics of a gold (Au) atom on the FeS surface. Furthermore, the effects of Fe/S vacancy and As/Sb dopant on Au adsorption were also investigated. The results reveal that the FeS(100) with S termination exhibits the smallest surface energy (0.56 J/m2) and possesses the highest stability amongst the low-index surfaces. Furthermore, the Au atom exhibits a preference for adsorption on the Fe-bridge site of FeS(100) through chemisorption due to the formation of a strong Au-Fe metallic bond, large adsorption energy (−5.40 eV), and small adsorption distance. Moreover, the presence of S vacancy enhances the Au capture capability of FeS(100) with an adsorption energy of −6.35 eV, while the Fe vacancy slightly weakens it. Additionally, the doping of As and Sb enhances the adsorption of Au atoms on FeS(100), and the Sb doping showcases a more distinct enhancement in Au capture efficiency. The findings of this work contribute to the advancement of matte processing technology, enabling enhanced gold recovery and potentially opening new avenues for the treatment of refractory gold ores.

Gold recovery from roasted refractory gold concentrate through cyclic extraction using MnO2-assisted thiocyanate leaching and cementation with zinc powder

Cyanidation has long served as the industrial standard in the gold industry, necessitating heightened attention to cyanide management owing to its inherent toxicity. This study developed a novel MnO2-assisted thiocyanate leaching system as an alternative to cyanide. The sample was generated from a refractory gold concentrate processed by roasting, containing 54.4 g/t gold with iron oxide and quartz as the major mineral phases. Within the framework of the novel system, gold recovery was investigated in terms of gold association, recovery behavior, thermodynamics, and optimization using cyclic extraction protocols. The most suitable leaching conditions were determined as 1.20 mol/L NaSCN, 4.00 mmol/L MnO2, pH at 1.00, liquid-to-solid ratio of 4 mL/g, and leaching duration of 24 h, resulting in a maximum gold extraction of 94.8%. Subsequent zinc precipitation facilitated a gold recovery of 99.4% from the leachate. Furthermore, the implementation of a cyclic extraction scheme, coupled with reagent addition to offset consumption, yielded a significant thiocyanate dosage reduction by 75% while maintaining gold recovery. This acidic leaching system yields satisfactory gold recovery with minimized reagent consumption, particularly suited for refractory gold ore that has undergone acidic pretreatment.

Study on high-efficiency sulfide removement using sulfate radical-based AOPs and its oxidation mechanism of refractory gold ore

Pyrite enclosure poses a significant challenge in refractory gold ore processing, inhibiting gold leaching. This study explores Sulfate Radical-based Advanced Oxidation Processes (SR-AOPs) as an effective alternative for pretreating such ores. The oxidation pretreatments were performed under heat and ultrasound activation methods, including heat and ultrasound, and the influences of pretreatment time, pH, ultrasound power, pretreatment temperature, and precursor (PDS) concentration were investigated. Both ultrasonic and heat activation effectively mitigate the negative impact of pyrite enclosure on gold leaching. Specifically, the gold leaching rate improved from 21.9 % to 46.1 % and 74.9 % with heat and ultrasound activation, respectively The and generated by PDS dominate the pyrite oxidation according to EPR and quenching tests. Meanwhile, the SR-AOPs treatment also promotes the interactions between pyrite enclosure and leaching agent, reducing the negative influences of pyrite. Kinetic studies indicated that the oxidation processes are different under heat and ultrasound activation. Heat activation is governed by an interfacial chemical reaction, with an activation energy of 25.57 kJ/mol. In contrast, ultrasound-induced cavitation and microjets remove the oxidation layer, disrupt the pyrite crystal structure, and expose encapsulated gold. These effects accelerate pyrite oxidation, shifting the kinetic control step from interfacial chemical reaction to internal diffusion, with a reduced activation energy of 35.06 kJ/mol.

Complete gold extraction and recovery from double refractory gold ores by thiourea after bio-oxidation

Cyanidation, a conventional process to extract gold from gold ores, has been used for over 130 years in industrial mining because of the high efficiency and rate of formation of Au(CN)2− and the high recovery efficiency by adsorption of Au(CN)2− on activated carbon. However, carbonaceous refractory gold ores are not targeted because Au(CN)2− is easily adsorbed on carbonaceous matter in the ores, resulting in high recovery loss. In this study, the flotation concentrates of a carbonaceous refractory gold ores was subjected to biooxidation at 45 °C using a mixed culture containing iron-oxidizing and sulfur-oxidizing bacteria, followed by gold extraction using thiourea under strongly acidic conditions. The gold extraction efficiency reached ∼100% in 12 h without re-adsorption. Finally, the quantitative recovery of the Au(CS(NH2)2)2+ complex was confirmed by adsorption on strongly cationic exchange resin. Biooxidation reduced the amount of Fe-containing metal sulfides, which minimized the decomposition of thiourea, and the Au(CS(NH2)2)2+ complex had a low affinity toward carbonaceous matter, different to Au(CN)2−. Since the process described in this study does not require roasting to remove carbonaceous materials in pretreatment and does not use cyanide for gold extraction, it is environmentally friendly and should be considered for practical applications in carbonaceous gold ore-producing mines.

Characterizing low-grade refractory gold ores using automated mineralogy coupled with LA ICP-MS

Researchers have made notable progress in quantifying refractory components causing gold losses in traditional extraction methods. The potential for improving gold recoveries lies in targeted re-treatment of the 'invisible' gold fraction hosted within various ore minerals, even at low concentrations. This study presents a methodology for analysing the refractory components that cause gold losses in traditional extraction methods. The approach utilizes automated mineralogical techniques in conjunction with in-situ laser ablation inductively coupled plasma mass spectrometry (LA ICP-MS) to characterize low-grade refractory ores and assess gold deportment. The methodology combines pre-concentration gravity separation, traditional chemical and mineral techniques, and LA ICP-MS to generate comprehensive datasets. To demonstrate the practical application of the methodology, a case study was conducted on historical tailings material from Witwatersrand's Evander Goldfield in South Africa. The case study aimed to determine the mineralogical distribution of gold that cannot be extracted through cyanidation. The results indicated that invisible gold is primarily hosted in pyrite (with an average concentration of 10.21 ppm representing 32 % of total gold), other sulphides (with an average concentration of 1.29 ppm representing 0.42 % of total gold), and oxides (with an average concentration of 0.50 ppm representing 1 % of total gold). The remaining gold is present in discrete fine cyanide amenable phases (with 28 % deportment) and silicate-hosted phases (with 39 % deportment). Environmental monitoring of the Witwatersrand tailings material revealed a net “acid-producing” nature, with high concentrations of heavy metals (such as As, Cu, Pb, Mn, Hg, and Ni) associated with sulphides (with over 78 % deportment). The deportment information obtained through this approach can optimize ore processing strategies and provide valuable insights for future remediation plans. By characterizing the refractory components causing gold losses and understanding the distribution of gold within the ore, this methodology offers the potential to enhance gold recovery and improve the efficiency of ore processing operations.

Exploring Non-ammoniacal Thiosulfate Gold Leaching and Limited Gold Recovery from a Refractory Gold Ore Oxidized in Alkaline Pressure Conditions

Exploring Non-ammoniacal Thiosulfate Gold Leaching and Limited Gold Recovery from a Refractory Gold Ore Oxidized in Alkaline Pressure Conditions

Pretreatment of refractory gold ore by curing with concentrated sulfuric acid

Pretreatment of refractory gold ore by curing with concentrated sulfuric acid

Effect of Power and Exposure Time on the Microwave-Assisted Roasting of Refractory Gold Ore

Reserves of high-grade gold ore worldwide are decreasing, and some industries have started processing refractory gold ore. Refractory gold ore contains sulfide minerals such as pyrite (FeS2), chalcopyrite (CuFeS2), galena (PbS), and sphalerite (ZnS). Gold in refractory ores occurs as fine-size gold-bearing sulfide minerals. In this study, the microwave-assisted roasting method has been investigated as a pretreatment for a refractory gold ore. This method can provide rapid heating radiation, cause micro-cracks, and trigger the decomposition of sulfide minerals. The presence of additive helps in the oxidation of sulfide minerals. The microwave-assisted roasting was carried out using variations in microwave power and time. Microwave power between 300 - 600 watts significantly affected the increase in roasting temperature and weight loss of refractory gold ore. The highest temperature reached 567°C in roasting at 800 watts for 30 minutes. The optimum condition for microwave roasting was achieved at 400 watts of power with a roasting time of 30 minutes. Metals extraction of Cu, Zn, Pb, and Fe reached 97.2%, 82.7%, 16.1%, and 2.1% in water leaching.

Pool bio-oxidation and fitting analysis of low-grade arsenic-containing refractory gold ore

To overcome the limitations of geography, climate, and ore characteristics on the ore beneficiation process, bio-oxidation studies on low-grade arsenic-bearing refractory gold ore by pool leaching were carried out, as well as process fitting analysis. The gold particles are encapsulated by pyrite and arsenopyrite. After 60 days of bio-oxidation, the oxidation rates of arsenic, sulfur, and gold were 39%∼69%, 24%∼41%, and 49%∼83%, respectively. The inoculated Acidithiobacillus ferrooxidans, Ferroplasma acidiphilum, and Leptospirillum ferrodiazotrophum could all mediate the initial pyrite/arsenopyrite oxidation and the Fe2+ oxidation reaction, but only the former could mediate the subsequent sulfur compound oxidation. When compared to daily bacterial circulation and bacterial replacement every ten days, aeration improved the gold leaching rate by 14%∼22%. The Boltzmann model could fit both the arsenic and sulfur bio-oxidation, with model fit variances greater than 0.98. Based on the experimental and fitting results, the bio-oxidation cycle was determined to be 60 days, and the bio-oxidation mechanisms are summarized. This study has significant practical implications for the rational utilization of gold resources and provides theoretical and practical guidance for similar gold ores.

Thermodynamic Behavior of Pyrite and Arsenopyrite in Preoxidation for Chlorination Leaching of Refractory Gold Concentrate

Recently, preoxidation is an effective pretreatment method of refractory gold ore, which has been widely used due to the high desulfurization, arsenic removal, low environmental pollution, and rapid reaction rate. In this paper, we describe the thermodynamic considerations of preoxidation of pyrite and arsenopyrite, the main minerals of the refractory gold ore, and the effect of the pressure oxidation, one of the preoxidation processes on the chlorination leaching. The thermodynamic results indicated that arsenopyrite under acidic conditions is easier to oxidize compared to pyrite and the oxidation decomposition of pyrite and arsenopyrite-type gold ore can be considered mainly for pyrite. The experiment has shown that the arsenic removal rate was higher than the desulfurization rate; it is confirmed that the thermodynamic conclusion of the oxidation of pyrite and arsenopyrite was correct. Comparing the XRD, SEM, and EDX analyses of gold concentrate and pressurized oxidation residue, it can be seen that the surface of pressurized oxidation residue is a fine porous structure and the dense and durable structure of sulfide ore is mainly destroyed.

Thiourea leaching of gold: Elucidating the mechanism of arsenopyrite catalyzed thiourea oxidation by Fe3+ and the beneficial role of oxalate through experimental and density functional theory (DFT) investigations

The combination of bio-oxidation pretreatment of refractory sulfide gold ore and thiourea leaching is a suitable method for gold extraction due to its environmental friendliness and compatibility in the two leaching systems. Arsenopyrite is an important auriferous sulfide mineral where the encapsulated gold can be effectively exposed by bioleaching pretreatment. The issue of high thiourea (TU) consumption, however, severely hinders the commercial application of this technology. In this paper, the effect of arsenopyrite on gold leaching in an acidic TU solution was investigated. Leaching results showed that the presence of arsenopyrite seriously impeded TU leaching of gold represented as the much decrease in gold dissolution and TU stability. The dominant cause for the detrimental effect of arsenopyrite was that arsenopyrite can catalyze the oxidation of TU by Fe3+ and thus bring about high TU consumption, further resulting in the marked deterioration of TU dissolution of gold. The catalytic mechanism is believed to be that TU adsorbs on arsenopyrite surface and then electrons transfer from TU to the oxidant Fe3+ through the conduction bands of arsenopyrite. Oxalate was used to improve TU stability and gold dissolution, and its mechanism was proposed as follows: oxalate not only weakened the interaction between Fe3+ and TU through complexing with Fe3+ but also competed with TU to absorb on the arsenopyrite surface, which decreased the TU adsorption. Besides, the formation of Fe-oxalate complexes, as the terminal electron acceptor, distinctly reduced the oxidation capacity of Fe3+, thus alleviating the catalytic effect of arsenopyrite on TU oxidation by Fe3+.

Оптимизация технологии обогащения бедной технологически упорной золото-углеродсодержащей руды

The processing of refractory gold ores is a challenging task. Refractory ores include ores that cannot be easily processed due to the fine dissemination of gold in sulphide minerals and the presence of preg-robbing carbonaceous matter. Two processes have been studied: flotation of low-grade double refractory gold ore ­using new carbon depression reagents; gravity – cleaner flotation of rougher flotation concentrate followed by pressure oxidation and the CIL treatment of POX cakes. The study is aimed to optimize the processing of low-grade (Au 0.6 g/t) refractory gold ore and achieve high process parameters. The study included the following steps: the reduction of organic carbon mass fraction (< 0.6 %) in concentrates reporting to hydrometallurgical treatment; experiments on the hydrometallurgical treatment of flotation concentrates using two process options: pressure oxidation (POX) of the initial flotation concentrate followed by the CIL treatment of POX cakes and preliminary gravity – cleaner flotation of the initial flotation followed by pressure oxidation and the CIL treatment of POX cakes. The research methodology is based on studying the influence of carbon depressant reagents on the flotation properties of organic carbon during the flotation process. When carrying out flotation experiments, the equipment of JSC Irgiredmet was used, installed at the semi-industrial testing site (laboratory mills, mechanical flotation machines and auxiliary equipment). The study is carried out in accordance with generally accepted methods of ore preparation and flotation concentration. The mass fraction of organic carbon in the flotation concentrate decreased from 2.0 to 0.5 %. It has been achieved by the use of new reagents for carbon depression (carbon depression reagents). The products of refractory gold ore flotation using new reagents for carbon depression were flotation concentrates suitable for further hydrometallurgical treatment. According to the experiments on rougher flotation concentrate pressure oxidation and subsequent POX cake cyanide leaching, the recovery of gold on the carbon adsorbent was 83.5 %. Preliminary gra­vity – cleaner flotation of the concentrate before pressure oxidation improved the loading of gold on the carbon adsorbent to 96.6 %.

Effect of Direct and Indirect Pre-Oxidation of Gold Ore from Doup North Sulawesi using Ozone Gas on the Gold Extraction in the Cyanidation Process

Refractory gold ore is a type of gold ore that is difficult to process when treated through a conventional cyanidation process. Pre-oxidation using ozone gas is one of the pre-treatment methods that can be used to improve gold recovery from sulfide-type refractory ore. This study used gold ore samples from Doup, North Sulawesi, Indonesia, to study the effect of direct and indirect pre-oxidation using ozone gas on gold recovery and subsequently treated by a cyanidation process. Direct and indirect pre-oxidation experiments were carried out at different pHs and using two raw materials for ozone generation (air and O2). The slurry obtained from the pre-oxidation experiments was filtered, and the filtrate was analyzed for the concentration of dissolved Cu, Fe, and Zn using atomic absorption spectroscopy (AAS); meanwhile, the residue from each pre-oxidation experiment was leached by cyanidation to obtain a pregnant leaching solution (PLS), which was analyzed for its gold concentration using AAS. The percentages of dissolved Cu, Fe, and Zn during pre-oxidation increased with the pre-oxidation time when the acidity was maintained at pH 2, using pure O2 as the ozone raw material. The direct pre-oxidation process at pH 2 using air as the ozone raw material increased gold extraction from 79.08% to 82.78% in the cyanidation process. The pre-oxidation experiments performed without controlling the pH resulted in lower gold dissolutions than the pre-oxidation conditions at pH 2. Possible causes of the lower gold dissolution were discussed.

Biooxidation of refractory sulfide-bearing ore using feroplasma acidophilum: Efficiency assessment and machine learning based prediction

The adhesive properties of microorganisms on the surface of minerals play an important role in the biooxidation efficiency of sulfidic refractory gold ores. In this research, the simultaneous effects of monosaccharides, ore content, pyrite content, and time on the activity and growth rate of Ferroplasma acidiphilum-from native Acid Mine Drainage (AMD)- was investigated during biooxidization alongside finding the best machine learning approach for the prediction of process efficiency using the independent variables. The results revealed that the optimum condition for reaching the highest pyrite dissolution (∼75 %) is 15 days of operating time, pyrite content of 7.2 wt%, and ore content of 5 wt%, pH of 1.47, and D-+-sucrose, D-+-galactose, and D-+-fructose concentrations of 0.52, 0.09, and 0.12 wt%, respectively. The results of the model comparison indicated that the Artificial Neural Network (ANN) model was able to predict the experimental results of this study with acceptable accuracy and better than Genetic Programming (GP) and Polynomial Regression informed by Response Surface Methodology (PR-RSM) from experimental data. Finally, the results showed that the change in D-+-fructose and D-+-galactose concentration has no significant effect on ferric ions concentration and pyrite dissolution content, while the influence of alteration in D-+-sucrose concentration is significantly high.

Catalysis of chalcopyrite on thiourea oxidation by Fe3+ and the advantage of oxalate during thiourea leaching of gold

Thiourea is a low-toxicity gold lixiviant that has promise to replace the highly toxic cyanide for gold extraction. Chalcopyrite is an important gold-bearing sulfide mineral, and thus investigation of its influence on gold leaching is important to maximize the utilization of refractory copper sulfide gold ore. In this paper, the effect of chalcopyrite on thiourea leaching of gold and the role of oxalate were studied through a series of leaching experiments, surface characterization and DFT calculation. Results showed that the presence of chalcopyrite severely hindered thiourea leaching of gold demonstrated as the greatly decreased in gold dissolution and thiourea stability. The detrimental effect of chalcopyrite was inferred to be the catalysis of chalcopyrite on thiourea oxidation by Fe3+, leading to the much-increased thiourea consumption, and thus deteriorated the gold dissolution. Oxalate as an additive was used to improve gold dissolution and thiourea stability. Oxalate not only weakens the interaction between Fe3+ and thiourea through complexing with Fe3+, but also competes with thiourea to adsorb on the chalcopyrite surface, decreasing thiourea adsorption. Besides, the formation of Fe-oxalate complexes, as the terminal acceptor of electron, significantly reduced the oxidizability of Fe3+, thus relieving the catalysis of chalcopyrite on thiourea oxidation.

Using Kerosene as an Auxiliary Collector to Recover Gold from Refractory Gold Ore Based on Mineralogical Characteristics

Carbon–arsenic-bearing gold ore is a typical complex refractory gold resource. Traditionally, xanthate was often used as a flotation agent to separate gold minerals. But, in this paper, in order to reduce the cost of the agent, kerosene was used as an auxiliary collector, and the gold grade and recovery rate were increased by about 10 g/t and 5.5%, respectively. Through process mineralogy studies of the raw ore, it was found that the ore has an Au grade of 5.68 g/t, most of which is surrounded by sulfide ore, accounting for 79.46%. The main minerals are pyrite, arsenopyrite, and quartz, etc. Their content, shape, particle size distribution, and occurrence state were obtained via microscopic observation and statistical analysis. According to the results of process mineralogy, various flotation conditions were tested, including grinding fineness, kerosene dosage, collector dosage, foaming agent dosage, and the slurry pH value. The optimal chemical system and the process flow of “two roughing, three cleaning and two scavenging” were finally determined, and the concentrate product with a gold grade of 42.83 g/t and recovery of 91.02% was obtained, which verified the feasibility of the kerosene-assisted xanthate flotation of refractory gold.