Ore Samples Research Articles

Chemical and mineralogical characterisation of Duguri Galena (Bauchi State, Nigeria)

This paper presents a detailed study of Galena samples' chemical and mineralogical properties collected from the Duguri area in Bauchi State, Nigeria. The sample for the research was sourced from Duguri town, Bauchi State, Nigeria. The sourced sample underwent comminution, homogenization, and sampling using the Coning and Quartering method followed by the Jones Riffle sampling method. Chemical analysis results of the crude ore sample showed the presence of Lead oxide (PbO) at an assay of 36.827 %, with Silica as the major gangue mineral present at 45.823 %. The other compounds present in the ore are ZnO (9.656 %), Fe2O3 (8.290 %), Al2O3 (3.409 %), TiO2 (1.072 %), WO3 (0.312 %), and AgO (0.001 %). Mineralogical Characterisation using XRD revealed the phases present in the ore as; Galena (47 %), Cerussite (19.0 %), Quartz (18.8 %), and Gratonite (15 %), hence confirming that the soured ore was Galena (PbS). SEM/EDS results showed the morphology of the sourced sample, containing Lead with other impurities in their quartz form within the ore matrix, with the presence of other elemental constituents (Si, C, and O). Keywords: Galena, Chemical analysis, Mineralogical characterisation, Duguri area, Bauchi State, Nigeria.

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.

Palladium and platinum minerals in Au-Pd ores of the Chudnoe deposit (Subpolar Urals, Russia)

Research subject. Minerals of palladium, platinum, and native gold, localized mainly in the veins of chromium-containing mica (fuchsite) in rhyolites. Aim. Clarification of the localization features of platinum group minerals, their species diversity, determination of the composition of minerals, relationships between precious metal minerals, establishment of the sequence of formation. Methods. Polished sections from ore samples and concentrates of heavy minerals mounted in epoxy resin were studied using optical and electron microscopes. The composition of minerals was determined using a scanning electron microscope with an energy dispersive spectrometer. Results. The main Pd minerals of the deposit are isomertieite/pseudomertieite and mertieite, the minor ones are ateneite and the unnamed Pd6BiSe mineral, and the platinum mineral is sperrylite. Isomertieite/pseudomertieite forms intergrowths with gold of any composition and structure, while mertieite occurs only with relatively low-copper gold of a homogeneous structure; therefore, significant areas of ore zones are characterized by the presence of one of the palladium arsenoantimonides. In some areas of ores, the replacement of isomertieite/pseudomertieite by mertieite wass established. Conclusions. The formation of fuchsite veinlets and the native gold, palladium minerals, and sperrylite contained therein is associated with one stage of mineral formation. Cr, Au, Pd, and Pt in ores form a single geochemical association, which indicates a common source of these elements. This source is most likely to be derivatives of basite-hyperbasite magmatism.

Genesis of the Neoarchean Algoma-type banded iron formation: constraints from Fe isotope and element geochemistry of the Qian’an iron deposit, eastern North China craton

Genesis of the Neoarchean Algoma-type banded iron formation: constraints from Fe isotope and element geochemistry of the Qian’an iron deposit, eastern North China craton

Variations in pore structures and permeabilities of ion adsorption rare earth ores during simulated in-situ leaching: Effect of newly formed clay particles and their swelling

Variations in pore structures and permeabilities of ion adsorption rare earth ores during simulated in-situ leaching: Effect of newly formed clay particles and their swelling

Co-Ni distribution and Re-Os isotopic age of the Wuxing complex in the Central Asian orogenic Belt: Implications for sulfide mineralization in Alaskan-type complexes

Co-Ni distribution and Re-Os isotopic age of the Wuxing complex in the Central Asian orogenic Belt: Implications for sulfide mineralization in Alaskan-type complexes

Characterization of evolution of reactive transport parameters during leaching process of sandstone uranium ore by combining porosity and lacunarity

Characterization of evolution of reactive transport parameters during leaching process of sandstone uranium ore by combining porosity and lacunarity

Cobalt and nickel distribution and controlling factors in the Bushveld layered complex

Cobalt and nickel distribution and controlling factors in the Bushveld layered complex

Microbial contribution to the formation of the Carboniferous sedimentary manganese deposits in northwestern China

Microbial contribution to the formation of the Carboniferous sedimentary manganese deposits in northwestern China

Investigation of Seasonal Variations in Glencore’s Kidd Creek Cu-Zn ore flotation

Investigation of Seasonal Variations in Glencore’s Kidd Creek Cu-Zn ore flotation

Hydrometallurgical Processing of a Low-Grade Sulfide Copper–Nickel Ore Containing Pt and Pd

The goal of the present work was to study the recovery of copper, nickel, and platinum group metals (PGMs) (Pt and Pd) from low-grade copper–nickel ore containing pyrrhotite, pentlandite, and chalcopyrite by column bioleaching followed by cyanidation. The ore sample contained the following: Ni—0.74%, Cu—0.23%, Fe—14.8%, Stotal—8.1%, and Ssulfide—7.8%. The Pt and Pd contents in the ore sample were 0.2535 and 0.515 g/t, respectively. Biological leaching in columns was carried out at 25, 35, and 45 °C for 140 days. A mixed culture of acidophilic microorganisms was used as an inoculum. Cu and Ni extraction depended on temperature, and at 45 °C, copper and nickel recovery was the highest, being 2.1 and 1.8 times higher than that at 25 °C, respectively. As a result, up to 35% of nickel and up to 10% of copper were recovered by bioleaching within 140 days. Bioleaching resulted in an increase in Pt and Pd recovery by cyanidation, but the effect on Pd recovery was insignificant. Pt recovery varied in the range of 3–40% depending on process conditions; Pd recovery was 44–55%.

Migration behavior of iron and phosphorus during gas-based reduction for high-phosphorus iron ore

Migration behavior of iron and phosphorus during gas-based reduction for high-phosphorus iron ore

Влияние состава гидроксамовых кислот на показатели флотации перовскита.

On a sample of perovskite-bearing ore of the testing of reagents-collectors from the class of hydroxamic acids, differing in the structure of the hydrocarbon radical, was carried out. The reagents based on octanoic acid and acids of vegetable oils — coconut and tall oil — were considered. It is shown that in the alkaline pH range the rough flotation is more active, and a considerable amount of gangue minerals is transferred to the froth product. Strong attachment of the collector on all minerals determines low efficiency of re-cleaning operations in alkaline conditions. The optimum pH of flotation is pH = 6.2–6.5. Increase in the length of hydrocarbon radical above 10 carbon atoms leads to a significant decrease in the selectivity of the collector action. Reagents based on coconut and tallic acids actively float both perovskite and gangue minerals. Of the reagents considered, octylhydroxamic acid is characterized by the most optimal flotation properties and provides obtaining perovskite concentrate with TiO2 ~49–50 %.

Leaching behaviour of limonite ores from Lapaopao, Southeast Sulawesi, Indonesia: Effect of mineralogy and acid types

An atmospheric leaching study of limonite ores from Lapaopao, Southeast Sulawesi, using hydrochloric acid (HCl), nitric acid (HNO<sub>3</sub>), and sulfuric acid (H<sub>2</sub>SO<sub>4</sub>) has been performed. The objectives of this study were to analyze the effect of ore mineralogy and acid types on the dissolution behavior of minerals and the leaching rate of Ni and Co at atmospheric pressure conditions. Mineralogical analysis was carried out using optical microscopy, scanning electron microscopy (SEM), and X-ray diffractometry (XRD), while the ore's chemical composition was determined by using X-ray fluorescence spectrometry (XRF) and atomic absorption spectrophotometry (AAS). Mineralogically, the limonite ores are dominated by goethite, followed by gibbsite, talc, and lizardite, with less amounts of hematite and quartz. Analysis results of solid residues revealed that mineral dissolution order was determined as follows: goethite > lizardite > gibbsite> hematite > talc> quartz. The results of the leaching experiment exhibited that the order of leaching rates of Ni in the three ores samples using three different acids were found as follows: Ore-1 > Ore-2 > Ore-3. Comparison of HCl, HNO<sub>3</sub>, and H<sub>2</sub>SO<sub>4</sub> as the lixiviants for the leaching of limonite ores demonstrated that HCl was the most reactive acid, followed by HNO<sub>3</sub> and then H<sub>2</sub>SO<sub>4</sub>. This might be due to the differences in mineralogical nature and reactivities of acids during the leaching process.

Isothermal reduction and comparative analysis of reaction kinetics of sponge iron produced from hematite-charcoal reaction using non-contact direct reduction method

Isothermal reduction and comparative analysis of reaction kinetics of sponge iron produced from hematite-charcoal reaction using non-contact direct reduction method

Optimizing multi-spectral ore sorting incorporating wavelength selection utilizing neighborhood component analysis for effective arsenic mineral detection

Arsenic contamination not only complicates mineral processing but also poses environmental and health risks. To address these challenges, this research investigates the feasibility of utilizing Hyperspectral imaging combined with machine learning techniques for the identification of arsenic-containing minerals in copper ore samples, with a focus on practical application in sorting and processing operations. Through experimentation with various copper sulfide ores, Neighborhood Component Analysis (NCA) was employed to select essential wavelength bands from Hyperspectral data, subsequently used as inputs for machine learning algorithms to identify arsenic concentrations. Results demonstrate that by selecting a subset of informative bands using NCA, accurate mineral identification can be achieved with a significantly reduced the size of dataset, enabling efficient processing and analysis. Comparison with other wavelength selection methods highlights the superiority of NCA in optimizing classification accuracy. Specifically, the identification accuracy showed 91.9% or more when utilizing 8 or more bands selected by NCA and was comparable to hyperspectral data analysis with 204 bands. The findings suggest potential for cost-effective implementation of multispectral cameras in mineral processing operations. Future research directions include refining machine learning algorithms, exploring broader applications across diverse ore types, and integrating hyperspectral imaging with emerging sensor technologies for enhanced mineral processing capabilities.

The behavior of pyrite during in-situ leaching of uranium by CO2 + O2: A case study of the Qianjiadian uranium deposit in the Songliao Basin, northeastern China

The behavior of pyrite during in-situ leaching of uranium by CO2 + O2: A case study of the Qianjiadian uranium deposit in the Songliao Basin, northeastern China

Cold plasma treatment: An innovative approach to reduce the moisture and the water reabsorption in iron ore concentrate

Wet beneficiation is a primary process employed by mining companies for iron ore concentration. The moisture content in the ore is a result of this beneficiation process, in addition to inherent moisture within the mineral composition. The moisture content of iron ore is a crucial parameter that requires effective control to ensure safe handling and transportation operations. Surface plasma treatment of iron ore has been investigated as a method to enhance the hydrophobicity of ore particles, thereby reducing residual moisture and water reabsorption by the particles. The samples underwent treatment using argon plasma and cold hexamethyldisiloxane (HMDSO) plasma, leading to the formation of a thin, silicon-rich surface layer. The treatments were applied to both polished ore samples and fine powder samples. The plasma treatment resulted in a reduction in moisture content and water absorption. The reabsorption of water decreased to approximately 35% of the pretreatment values. Contact angle measurements demonstrated that all HMDSO-treated samples exhibited hydrophobic behavior, with contact angles ranging from 110° to 120°, while the untreated samples exhibited angles close to 0°. Furthermore, atomic force microscopy (AFM) topographic imaging revealed a granular structure in the thin films.

Miniaturizing Hyperspectral Lidar System Employing Integrated Optical Filters

Hyperspectral LiDAR (HSL) has been utilized as an efficacious technique in object classification and recognition based on its unique capability to obtain ranges and spectra synchronously. Different kinds of HSL prototypes with varied structures have been promoted and measured its performance. However, almost all of these HSL prototypes employ complex and large spectroscopic devices, such as an Acousto-Optic Tunable Filter and Liquid-Crystal Tunable Filter, which makes this HSL system bulky and expensive, and then hinders its extensive application in many fields. In this paper, a smart and smaller spectroscopic component, an intergraded optical filter (IOF), is promoted to miniaturize these HSL systems. The system calibration, range precision, and spectral profile experiments were carried out to test the HSL prototype. Although the IOF employed here only covered a wavelength range of 699–758 nm with a six-channel passband and showed a transmittance of less than 50%, the HSL prototype showed excellent performance in ranging and spectral profile collecting. The spectral profiles collected are well in accordance with those acquired based on the AOTF. The spectral profiles of the fruits, vegetables, plants, and ore samples collected by the HSL based on an IOF can effectively reveal the status of the plants, the component materials, and ore species. Finally, we also showed the integrated design of the HSL based on a three-dimensional IOF and combined with a detector. The performance and designs of this HSL system based on an IOF show great potential for miniaturizing in some specific applications.

Characterization of metal-bearing nanoparticles observed in loess-covered terrain: Implications for prospecting

Characterization of metal-bearing nanoparticles observed in loess-covered terrain: Implications for prospecting