us7794677b2 reduction of copper content in themethods and systems for removing copper minerals from a molybdenite concentrate. one embodiment provides leaching copper from the molybdenite concentrate with a leaching solution comprising ferric chloride, removing molybdenite from the leaching solution, introducing an acid into the leaching solution and introducing o 2 , o 3 , or a combination of both, into the leaching solution.a kinetic study of the leaching of molybdenite springerlinkup to10%cash back· under these conditions molybdenite was found to leach according to a linear mechanism. both oxygen overpressure and koh concentration were found to control the rate of leaching. the mechanism has been explained in terms of adsorption of oxygen at the molybdenite surface followed by configurational rearrangement of the adsorbed molecules.cited by 9development of a mathematical model of aa molybdenite leaching process by geoffrey josep parsonh s b.sc.(tech.) with merit, univ o. f new south wales , australia, 73 a thesis submitted in partial fulfillment of the requirements for the degree of master of applied science in the faculty of graduate studiesbioleaching of molybdenite researchgateleaching of molybdenite concentrate with hydrogen peroxide in sulfuric acid solution was investigated to determine the effects of reaction time, reaction temperature, h5o2 concentration, h5so4mechanism and leaching kinetics of molybdenite, a leaching time of 70 s (2 h), a temperature of 368 k (95°c), a solid/liquid ratio of 1, an ore particle size of 74 µm and an agitation speed of 600 r/min. the reaction was chemically controlled, and the calculated apparent activation energy of molybdenite leaching was 40.4 kj/mol.kinetics of pressure oxidative leaching of molybdenitejan 01, · in a study on atmospheric leaching of molybdenite concentrate in nitric acid solution, vizsolyi proposed the following reaction (vizsolyi and peters, 80) (1) mos 2 + 6hno 3 h 2 moo 4 2h 2 so 4 + 6no(g). reaction 1 is a very slow reaction (reaction completed in 96 h) and acid consuming (9 m hno 3 solution).cited by 34comparative study on the selective chalcopyritemar 01, 01· chemical leaching tests with fe 3+ confirmed that the chalcopyrite dissolution mechanism in the presence of molybdenite is mainly indirect. according to this mechanism, ferric iron is the main oxidizing agent for the decomposition of the mineral sulfide and therefore, the regeneration of this agent is a function of the microorganisms.acidic leaching with chlorate as oxidizing agent tojun 23, · the technology of molybdenum extraction from molybdenite concentrate by using potassium chlorate (kclo 3) or sodium chlorate (naclo 3) has been investigated.the results show that leaching time, leaching temperature, agitation speed, oxidizer type, potassium or sodium chlorate, and hydrochloric acid concentration have significant effect on the molybdenum extraction efficiency.
copper removal from molybdenite by sulfidationleachingup to10%cash back· the process involves a sulfidation of the molybdenum concentrate with 82(g) at 380 °c followed by a leaching stage. h 2 so 4naclo 2 leaching of a sulfidized concentrate containing 3.4% cu for 90 min at 100°c produced a molybdenite concentrate with less than 0.2% cu, which is appropriate for marketing. molybdenite dissolution was negligible in these conditions.cited by 2autoclave leaching of molybdenite concentrates withthe scientific theoretical prerequisites for the use of small additives of nitric acid for the intensification of the autoclave oxidative leaching (aol) of sulfide concentrates are checked in order to increase the degree of extraction of the base metal with a simultaneous decrease in the cost of the process. the technological parameters of the aol conditions applied to molybdenite are alsothe alkaline leaching of molybdenite flotation tailingsnov 01, · within the molybdenite flotation tailings associated with galena, the pb and mo mainly occur as sulfides. whereas the oxides of pb and mo leach easily with naoh, the sulfides leach very slowly until they are converted into the oxides. therefore, the purpose of preroasting is to oxidize the sulfides to either oxides or sulfates.cited by the alkaline leaching of molybdenite flotation tailingsa method for the extraction of both pb and mo from molybdenite flotation tailings associated with galena is described. the flotation tailings were preroasted and then alkaline leached. the effect of temperature, initial concentration of sodium hydroxide solution, alkali to total calcine mass ratio, leaching time and stirring speed on theleaching molybdenum from a lowgrade roastedmar 07, · up to10%cash back· the leaching molybdenum from lowgrade molybdenite concentrate has been widely investigated, mainly in relation to acidic oxidative leaching for the direct extraction of molybdenum [,,22]. the advantages lie in no so 2 emission but the impurities such as iron, calcium, magnesium, phosphorus and arsenic et al. are also dissolved in the leaching solutions.cited by 1recovery of molybdenum and rhenium using selectivea study has been conducted for the separate recovery of molybdenum and rhenium from alkali leaching solution of molybdenite roasting dust by a selective precipitation method. two kinds of synthetic alkali leaching solutions were employed and more than 85% of molybdenum was recovered as a precipitate in the experimental conditions of 243.k, ph mechanism and leaching kinetics of molybdenitethe mechanism and leaching kinetics of a molybdenite concentrate in a h5o2h5so4 system were studied. the experimental work was performed in a batch reactor equipped with a condenser, a mechanical agitator and a temperature control system. the effects of the temperature, h5o2 and h5so4 concentrations, particle size, liquid/solid ratio and agitation speed on the mo recovery were investigated.investigating the effect of mechanical activationthe results demonstrate that alumina has a motivating effect in activation procedure to achieve a nanostructure molybdenite. analysis of variance revealed milling speed is the main parameter in ma without alumina, while, ball to powder ratio is the most important factor in ma procedure in presence of alumina on leaching ratemolybdenum processing imoaflotation separates the metallic minerals from the gangue this way and in the case of copper/ molybdenum ores separates molybdenite from copper sulphide. the resulting mos 2 concentrate contains between 85% and 92% mos 2. further treatment by acid leaching can be used to dissolve impurities like copper and lead if necessary.
leaching use of a thermophilic and chemoautotrophica chemoautotrophic, thermophilic, and acidophilic microorganism capable of oxidizing reduced sulfur and iron compounds and leaching concentrates of molybdenite and chalcopyrite at 60 degrees c has been characterized by transmission and scanning electron microscopy. this constitutes the first direct observations of microorganisms on ore fines.determination of optimal conditions for pressure oxidativedetermination of optimal conditions for pressure oxidative leaching of sarcheshmeh molybdenite concentrate using taguchi method (naslov ne postoji na srpskom) khoshnevisan a., yoozbashizadeh h. department of materials science and engineering, sharif university of technology, tehran, iranrecovery of molybdenum from leach solution usingdec 01, · the most probable reaction for nitric acid leaching of molybdenite is as follows (vizsolyi and peters, 80) (1) mos 2 + 6hno 3 moo 3 · nh 2 o + 2 h 2 so 4 + 6 no + 1 n h 2 o solid to liquid ratio of 1.3g/l was selected to prevent saturation of molybdenum in solution (shalchian et al., ; vizsolyi and peters, 80).cited by 3leaching and kinetic modelling of molybdenite concentrateas an oxidizing agent for the leaching of sulfide minerals such as sphalerite and chalcopyrite  and it is therefore natural to consider its use for the treatment of molybdenite. the reaction of molybdenite with acidic h. 2. o. 2. can be expressed as follows mos 8h o 8h o mo(so ) 2 2 2 2 + + 42 (1)selective copperiron dissolution from a molybdenitejun , 01· selective copperiron dissolution from a molybdenite concentrate using bacterial leaching patricia romano department of materials science and metallurgical engineering, facultad de ciencias químicas, universidad complutense de madrid, 28040 madrid, spainbioleaching of molybdenite sciencedirectjul 01, 08· bioleaching rates of molybdenite also increased with temperature, by a factor of about 2.5 for a 10 °c rise up to 40 °c . mo was bioleached from molybdenite in the composite mineral processing waste material at 2.5%/day at 25 °c, increasing to 10.2%/day at 40 °c . data over the first 40% to 60% mo extraction were fit to a shrinking particle model for determination of bioleaching rates.cited by 81factors influencing the recovery of molybdenum during thethe leaching of molybdenite copper concentrates in acid solutions was studied, and results showed that such a process would not be feasible due to the formation and precipitation of copper molybdate, cumoo. this compound is very insoluble, but its formation was found to be suppressed by the presence of sodium bicarbonate at ph values