Mingyu Wang

Effect of vanadium occurrence state on the choice of extracting vanadium technology from stone coal

Abstract The extraction technology of vanadium from stone coal by means of no-salt-roasting and dilute acid solution leaching treatment has the advantages of low pollution, low investment, as well as high vanadium leaching efficiency, which makes it the best technology for extending application. In the present study, the effects of vanadium occurrence state in stone coal, roasting temperature and additive agent on the leaching efficiency of vanadium were studied. The results indicate that the effect of vanadium occurrence state on the extracting vanadium technology is obvious. If the vanadium component in stone coal existed in amorphous phase form, this type of stone coal can be treated by no-slat-roasting and dilute acid solution leaching technology; while the vanadium-bearing crystalline phase existed in stone coal, the roasting additive must be added to destroy this crystalline form so as to acquire high vanadium leaching rate.

Selective enrichment of TiO2 and precipitation behavior of perovskite phase in titania bearing slag

Abstract The effects of additive agents and growth behavior of perovskite phase as well as temperature change of slag at semi industry scale test were studied. The results show that the increase of steel slag does good to titania enrichment, however, it isnt useful for the growth and coarsening of the perovskite phase. The additive Si-Fe powder can promote titania enrichment and make perovskite phase grow up easily. While air is blown into the molten slag, the reduced components in slag are oxidized and the released heat raises the temperature of slag.

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 90xa0% at pH of 0.5, contact time of 10xa0min, 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 60xa0g·L−1 ammonium acid carbonate solution is 94.67xa0% at O/A ratio of 2:1 and contact time of 10xa0min.

Effect of oxidization on enrichment behavior of TiO2 in titanium-bearing slag

Due to the dispersed distribution of the titanium component in various mineral phases and very fine grain size, it is difficult to recover the titanium component from the slag. In order to utilize titanium resources, selective enriching and selective growing of the titanium component from the molten slag is expected. In this paper, the selection of the best titanium enrichment phase and the effect of oxidization on the enrichment of titanium by blowing air into the molten slag were studied. The results showed that through oxidizing the slag, the content of the perovskite phase increases while that of the other titanium-bearing mineral phases decreases until they disappear. Most titania resources were enriched into the perovskite phase and increase in size. The process of enrichment and growth is easily carried out.

Isothermal precipitation and growth process of perovskite phase in oxidized titanium bearing slag

Abstract The isothermal precipitating behavior of perovskite phase in oxidized titanium bearing slag was studied by quenching method. The kinetics of precipitating process and crystal growth of perovskite phase was analyzed. The results show that the precipitating and growth of perovskite are non-equilibrium process at the beginning of isothermal treatment. There are two factors influencing the growth rate of perovskite phase on non-equilibrium condition, one is the supersaturation concentration of perovskite and the other is the coarsening arising from the growth of larger perovskite at the expense of smaller ones. The precipitation kinetics of perovskite phase can be nearly described by the JMAK equation.

Separation of Iron Droplets From Titania Bearing Slag

Owing to smelting vanadium-titanium magnetite ore, the amount of iron entrainment in slag as droplets is far higher than that in conventional BF slag. However, the iron droplets can be easily settled by blowing air into the molten slag. The results show that more than 80% of iron droplets in titania bearing slag can be settled and separated after treatment. The temperature rise of molten slag during the oxidizing process and the decreased viscosity caused by the component change of slag as well as air stirring in slag both accelerate the iron droplets settling. The vanadium content in the settled iron droplets and the original iron droplets was obtained by chemical analysis. The possible reason for the increased vanadium in the settled iron droplets was discussed by thermodynamic principles.

Leaching behaviour of chromium during vanadium extraction from vanadium slag

Abstract In order to recover chromium from vanadium slag, the leaching behaviour of chromium during vanadium extraction was studied. The effects of the several parameters that included roasting temperature, roasting time, types of additives as well as addition mass of additives were investigated. The results indicated that chromium can be leached at the same time during vanadium leaching from vanadium slag. In comparison, under the same conditions, the leaching of vanadium is easier than that of chromium. The leaching rate of vanadium and chromium can be beyond 96 and 91%, respectively, under the experimental condition of roasting temperature of 700°C, roasting time of 2 h, 30% (mass fraction) sodium chloride and 20% (mass fraction) sodium carbonate addition to the vanadium slag, leaching temperature of 95°C, and leaching time of 3 h.

Extraction of molybdenum and nickel from roasted Ni–Mo ore by hydrochloric acid leaching, sulphation roasting and water leaching

Abstract To extract molybdenum and nickel from the roasted Ni–Mo ore, a process of hydrochloric acid leaching, sulphation roasting and water leaching was investigated. The results showed that this process could get a high leaching rate of Mo and Ni. Under the optimum conditions of hydrochloric acid leaching (roasted Ni–Mo ore leached with 0.219 mL/g hydrochloric acid addition at 65 °C for 30 min with a L / S ratio of 3 mL/g), sulphation roasting (51.9% sulfuric acid addition, roasting temperature 240 °C for 1 h), followed by leaching with the first stage hydrochloric acid leaching solution at 95 °C for 2 h, the leaching rates of Mo and Ni reached 95.8% and 91.3%, respectively.

Existing form of Mo(VI) in acidic sulfate solution

The existing form of molybdenum in acidic sulfate solution was studied by means of ion exchange, infrared (IR) spectra and X-ray photoelectron spectroscopy (XPS). The results indicate that the anionic molybdenum species are predominant in acidic sulfate solution, and Mo(VI) can combine with sulfate radical to form heteropoly acid anions [Mo2O5(SO4)2]2− and [MoO2(HSO4)4]2−. With the decrease in solution pH from 1.92 to 0.06, the existing form of Mo(VI) changes from Mo7O21(OH)33− to [Mo2O5(SO4)2]2− and then becomes [MoO2(HSO4)4]2−, which results in the decrease in the resin adsorption capacity for molybdenum.

Extraction of molybdenum from acidic leach solution of Ni–Mo ore by solvent extraction using tertiary amine N235

ABSTRACT Tertiary amine N235 diluted with sulphonated kerosene containing sec-octyl alcohol as a phase modifier was used to directly extract molybdenum from the acidic leach solution of Ni–Mo ore. The results indicated that the extraction of molybdenum can reach more than 88% using a solvent extraction system consisting of 10u2005vol.-% N235 and 10u2005vol.-% sec-octyl alcohol in sulphonated kerosene with an O/A ratio of 1:2 at room temperature for 20u2005min. The extracted molybdenum species of Mo7O21(OH)33–, MoO2(SO4)22– and MoO2(HSO4)42– in loaded organic phase were identified, and the predominant species was Mo7O21(OH)33–. Molybdenum in the loaded organic phase can be stripped with ammonia solution, and the stripping of molybdenum can reach 95.8% at an O/A ratio of 7:1, phase contact time of 10u2005min, and the ammonia concentration of 6u2005molu2005L−1.