Aerosol flotation of low-grade refractory molybdenum ores

The characteristics of aerosol flotation, which include the effect of the concentration and particle size of kerosene aerosol on the molybdenum （Mo） flotation index and the effect of kerosene aerosol dosing method on the kerosene dosage and flotation time, were studied in the flotation of low-grade refractory molybdenum ores using kerosene aerosol. The results revealed that the particle size and concentration of kerosene aerosol had little effect on the Mo grade but had significant effect on the Mo recovery. A smaller particle size and a lower con-centration of kerosene aerosol were beneficial to the Mo aerosol flotation. For the received Mo ore samples, the optimized particle size of kerosene aerosol was 0.3-2 μm and the optimized aerosol concentration was 14 mg/L. The compressed air atomizer had a more uniform dis-tribution of aerosol particles than the ultrasonic atomizer, and the aerosol concentration was controlled easily, so the compressed air atomizer was more suitable for the research of aerosol flotation. Compared with conventional flotation in which kerosene was directly added into the ore pulp, the flotation time was reduced by ~30%, and the dosage was decreased by ~20% in aerosol flotation, while the Mo flotation index was similar.

Flotation technology of refractory low-grade molybdenum ore

Because of the low grade, high oxidation rate and the accumulation of little associated metal sulfide ore in the molybdenum concentrate during flotation, the Qingyang molybdenum ore is difficult to beneficiate. The experimental studies of grinding fineness, the amount of roughing modifier, depressant and collector were completed. In the cleaning process, the contrast experiments of one regrinding, the regrinding and scrubbing, two-stage regrinding was carried. The result shows that the grade of molybdenum ore concentrate is 45.31%, the recovery is 65.98% and the rich ore ratio reaches 20.59% by the regrinding and scrubbing seven cleaning, the regrinding of concentrations from middling of molybdenum-sulfur separation. The regularly-concentrated material from the apparatus was as the middling products. Hence, ideal beneficiation index can be obtained with a rational mineral processing, which offers new beneficiating technology for the refractory low-grade molybdenum ore in China.

Magnetic Method Surveying and Its Application for the Concealed Ore-Bodies Prospecting of Laba Porphyry Molybdenum Ore Field in Shangri-La, Northwestern Yunnan Province, China

Recently, a number of large molybdenum (-copper) deposits have been discovered successively in the Laba area, Shangri-La county, northwestern Yunnan province. The investigation confirmed that there is a superlarge porphyry-skarn hydrothermal vein type molybdenum-polymetallic- metallogenic system with the total prediction reservoir of more than 150 mt molybdenum. The porphyry intrusions contributed to the mineralization closely, the superficial little vein molybdenum (-copper, lead, silver) ore-bodies are usually located in faults and fractures, and the deep porphyry type ore-bodies occurred in the granodiorite porphyries, the skarn type ore-bodies occurred in the contact zone intrused into Triassic limestone or Permian basalts. Laba ore block is a new exploration area with great prospecting potential. In order to reduce the target area and guide the further exploration work, the magnetic method measurement about 3.3 square kilometres was carried out in the ore field. This paper presents an application of analyzing the horizontal and vertical derivative, using Fast Fourier Transform (FFT) filter (FFT high-pass, low-pass, cosine roll-off, suscepbility), calculated spectra frequency energy to predict the depth and intensity of the apparent remanence magnetization of source (Hilbert). The calculated results and magnetic anomalous show that the remanence anomaly is caused by the intrusions into the Triassic limestone and Permian basalts with small anomalies, and the depth of located source is not great. We have identified a number of positions to the three drilled well, the drilled result specify interpretation with very high accuracy. The magnetic method is helpful to identify porphyry mineralization, and judge the shape and depth of the concealed ore-bearing intrusive bodies under the similar geological condition.

Geology and Geochemistry of the Shizitou Molybdenum Deposit, Jiangxi Province： Implications for Geodynamic Setting and Metallogenesis

The Shizitou molybdenum （Mo） deposit in Yongping, Jiangxi, is an important, recently discovered deposit in the eastern section of the Qin-Hang metallogenic belt. The Mo deposit is located in the outer contact zone behveen the porphyritic biotite granite and the Neoproterozoic migmatite, and present in the deep central part of the intrusion. Re-Os dating and S and Pb isotopic analysis have been conducted to assess the metallogenesis of the Shizitou Mo deposit. S, Pb and Re isotopes show that the ore-forming materials were derived from the porphyritic biotite granitic magma, which originated from the mixing of mantle and crust. Re-Os dating of molybdenite from the ores gives a model age from 156.9±2.2 to 158.5±2.4 Ma, with a weighted mean age of 158±1 Ma and an isochron age of 158.0±2.5 Ma. Geological and geochemical characteristics of the ore deposit and the related granitoids indicate that the Shizitou deposit is a Climax-type Mo deposit. Based on previous studies of the Qin-Hang metaliogenic belt, two metallogenic events are believed to have occurred during 172-145 Ma and 137-132 Ma. These two metallogenic periods are consistent with the timing of two metallogenic peaks during the middle to late Jurassic and the Cretaceous in South China. These events represent responses to the partial backarc extension associated with the subduction of the Izanagi plate beneath the Eurasian continent and the rapid northeastward movement of the subducting Izanagi plate.

Extraction of Tungsten and Molybdenum by Various Organic Compounds as Extractants

Seventy organic compounds including various organophosphorus esters, amines and oxygen-based ligands were investigated as extractants. The experiment results show that amines are excellent extractants for W and Mo. Their sequence of extraction ability for W is as follows: quarternary amine > tertiary amine > secondary amine > primary amine. Acidic organophosphorus extractants do not extract W, but can extract Mo with high extraction ability from the acidic solution. These extractants could provide a potential process for separating W from Mo.

Differences in arsenic, molybdenum, barium, and other physicochemical relationships in groundwater between sites with and without mining activities

The characteristic relationships of trace metals and other water quality parameters in a specific region can be affected by anthropogenic activeties. Since the mid-18th century in the southwestern part of the Baja California Peninsula, intermittent gold mining activities have been developed. We analyzed 36 water quality parameters in accordance with the procedures suggested by international agencies to evaluate the impact of this activity and the time of year on the mobilization of trace element levels and their relationships in groundwater. Quantifiable levels of molybdenum help to establish the area influenced by ore deposits because it is one of the three elements in the paragenesis associated to gold. Arsenic in sites closer to ore burning areas was associated with cobalt, indicating the potential presence of a by-product generated from arsenolite;whereas in the non-mineralized area, it was associated with barium, forming a compound that tends to precipitate, thereby maintaining a natural geochemical control in this region. From the sites sampled, 45% exceeded the limit for arsenic (10 μg/l) established by international agencies. During area monitoring with annual precipitation of 207 mm, only seven of 36 parameters analyzed showed significant differences in relation to time of year.

Superior lithium storage performance in MoO_(3) by synergistic effects:Oxygen vacancies and nanostructures

Molybdenum trioxide(MoO_(3))has recently attracted wide attention as a typical conversion-type anode of Li-ion batteries(LIBs).Nevertheless,the inferior intrinsic conductivity and rapid capacity fading during charge/discharge process seriously limit large-scale commercial application of MoO_(3).Herein,the density function theory(DFT)calculations show that electron-proton co-doping preferentially bonds symmetric oxygen to form unstable HxMoO_(3).When the-OH-group in HxMoO_(3) is released into the solution in the form of H_(2)O,it is going to form MoO_(3-x)with lower binding energy.By the means of both electron-proton co-doping and high-energy nanosizing,oxygen vacancies and nanoflower structure are introduced into MoO_(3) to accelerate the ion and electronic diffusion/transport kinetics.Benefitting from the promotion of ion diffusion kinetics related to nanostructures,as well as both the augmentation of active sites and the improvement of electrical conductivity induced by oxygen vacancies,the MoO_(3-x)/nanoflower structures show excellent lithium-ion storage performance.The prepared specimen has a high lithium-ion storage capacity of 1261 mA h g^(-1)at 0.1 A g^(-1)and cyclic stability(450 cycle),remarkably higher than those of previously reported MoO_(3)-based anode materials.

Solvent extraction of molybdenum from acidic leach solution of Ni–Mo ore

A P204 （D2EHPA） diluted with sulfonated kerosene was used for the selective extraction of molybdenum from an acidic Ni-Mo ore leach solution that was reduced using sodium thiosulfate. The results indicate that P204 （D2EHPA） is an effective extractant for the extraction of molybdenum. The extraction of Mo is more than 90 % at pH of 0.5, contact time of 10 min, and organic-to- aqueous phase （O/A） ratio of 1：1 with 10 vol% P204 （D2EHPA）. Molybdenum in the loaded organic phase can be effectively stripped with ammonium acid carbonate solution, and the stripping of molybdenum with 60 g.L-1 ammonium acid carbonate solution is 94.67 % at O/A ratio of 2：1 and contact time of 10 min.