Showing papers in "Hydrometallurgy in 2007"

TL;DR: In this article, a review of metallurgical processes for manganese production from various resources, particularly focusing on recent developments in direct hydrometallurgical leaching and recovery processes, is presented.

TL;DR: In this article, the metal bio-leaching capability of Sulfobacillus thermosulfidooxidans and an unidentified acidophilic heterotroph (code A1TSB) isolated from local environments was investigated.

TL;DR: In this paper, a chemically modified chitosan resin resin with magnetic properties has been investigated for recovery of Au(III) and Ag(I) from their aqueous solutions using batch and column methods.

TL;DR: In this article, the characteristics of NaOH-, KOH- and NH 4 OH-oxalic acid mixtures were also determined in the presence of oxalate concentration, solution pH and temperature.

TL;DR: In this paper, the behavior of impurity elements during a copper recovery process from waste printed circuit board (PCB) using ammonia-ammonium sulfate and chloride systems are examined and the performance of these two systems are compared.

TL;DR: In this article, the main methods for manganese separation and recovery from solution are reviewed, which are potentially applicable to leach solutions of secondary menganese sources, particularly nickel laterite waste effluents.

TL;DR: In this article, the authors reported the results of a laboratory investigation on the long-term stability of crystalline scorodite conducted at fixed pH (5−9) and temperature (22,°C, 50 −°C and 75−°C).

TL;DR: In this article, the dissolution kinetics of an iron-rich zinc sulphide concentrate in acid ferric sulphate medium were examined and the effects of temperature, ferric ion and sulphuric acid concentrations, agitation speed and particle size on the leaching kinetics were investigated.

TL;DR: In this paper, the authors determined the predominant chemical reaction during the precipitation of ammonium uranyl carbonate (AUC) based on thermodynamic analysis and investigated its kinetics.

TL;DR: In this article, the application of 1-butyl-3-methyl-imidazolium hydrogen sulphate (bmim+(HSO4−)) ionic liquid and close analogues is described as a solvent medium (either as a neat liquid and or as aqueous mixtures) for the leaching of gold, silver, copper and base metals from sulphidic ores using thiourea (mainly) in the presence of iron(III) as oxidant.

TL;DR: In this article, a bio-leaching process was attempted by using chemo-lithotrophic sulfur oxidizing bacteria to recover valuable metals from vanadium-rich spent refinery catalysts.

TL;DR: In this paper, the authors compared the kinetics and products from the pressure oxidation of a chalcopyrite concentrate under a range of reaction conditions promoted by various companies, including the Phelps Dodge-Placer Dome and Activox® processes.

TL;DR: In this article, the influence of sodium chloride on the leaching of chalcopyrite focusing on surface area and porosity of the reaction products formed during leaching was evaluated.

TL;DR: In this paper, the authors evaluated the ability of At. ferrooxidans and other acidophiles to adhere to pyrite ore, glass beads and ferric hydroxysulfates.

TL;DR: The use of persimmon peel gel for the recovery of Au(III) from aqueous chloride medium was investigated in this paper, where the gel was found to be selective only for Au (III).

TL;DR: In this article, a comprehensive modelling study of the HydroZinc™ heap bioleach process, using the HeapSim modeling tool, is described, and a set of improved design parameters are proposed that would almost double the zinc conversion rate measured in the pilot plant, and increase zinc production rate from 1.77 to 4.35 kg/m 2 /day.

TL;DR: In this article, the effects of particle size (0.038-0.075mm), temperature (30-50°C) and initial acid concentration (0,2-1.0mol/L) on the leaching of a zinc silicate concentrate in sulphuric acid were studied.

TL;DR: In this paper, a simple hydrometallurgical method for the selective recovery of cadmium and nickel from spent Ni-Cd batteries was proposed, where the following consecutive stages are proposed: dismantling, leaching in sulphuric acid, Cadmium electrowinning, Fe3+ removal and nickel electrowining.

TL;DR: In this paper, the liquid-liquid extraction of mercury (II) from hydrochloric acid solutions using Aliquat 336 (tri-octyl methylammonium chloride) as extractant dissolved in commercial kerosene Exxsol D-80 has been investigated.

TL;DR: In this article, the results of the determination of the leaching characteristics of TiO 2 from ilmenite by hydrochloric acid have been presented, where the acid concentration and solid/liquid ratio were investigated.

TL;DR: In this article, an analytical analysis of an artificial matte was carried out to investigate the extraction behavior of copper, nickel, and cobalt in an oxidative ammonia/ammonium sulphate leaching process.

TL;DR: In this article, the results of an investigation on the H 2 SO 4 -O 2 pressure leaching of sulfidized chalcopyrite is presented, and the variables considered in the study were stirring speed, concentration of sulfuric acid, temperature, and partial pressure of oxygen.

TL;DR: A batch process was developed to separate Sm, Eu, and Gd from the lanthanide hydrous oxide cake produced from monazite mineral of the Egyptian beach black sand deposits after Ce-separation.

TL;DR: In this article, the recovery of silver from hydrometallurgical leach residues of lead-zinc sulfide concentrates using non-cyanide reagents was investigated.

TL;DR: In this paper, the extraction of lead from a galena concentrate in nitric acid solutions with additional hydrogen peroxide was studied taking stirring speed, temperature, hydrogen peroxidation and Nitric acid concentrations, and particle size as dissolution parameters.

TL;DR: In this paper, the authors compared the effect of additives on the dispersion of molten sulfur and recovery of copper, and developed a better understanding of the role of chloride ion, which suggests that chloride ion is adsorbed on the sulfur surface to restrict direct oxygen reaction.

TL;DR: In this article, the authors investigated the preferential flow in dump leaching of low-grade ores and found that preferential flow happened in the fine region at an application rate below 1070 L/m 2 min.

TL;DR: In this paper, the recovery of nickel from a low-grade chromite overburden was attempted by employing two fungal strains, Aspergillus niger and A. fumigatus, and a mixed culture of mesophilic acidophiles (predominantly acidithiobacillus ferrooxidans).

TL;DR: In this article, the effect of the change in phase constitution, particle size distribution, surface area, crystallite size, strain and lattice parameters introduced by mechanical activation of the altered beach sand ilmenite from Manavalakurichi region, India on the dissolution kinetics of HCl and H2SO4 was investigated.

TL;DR: Low grade powdery zinc oxide ores (5.2% Zn, − 2 ǫ day − 1, 8.09 − 10 − 3 ǔday − 1, 4.74 − 10−3 ǒ day − 2 ) were mined in this paper.