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[Mo_2O_5(SO_4)_2]^(2-) and[MoO_2(HSO_4)_4]^(2-).With the decrease in solution pH from 1.92 to 0.06,the existing form of Mo(VI) changes from Mo_7O_(21)(OH)_3^(3-) to[Mo_2O_5(SO_4)_2]^(2-) and then becomes[MoO_2(HSO_4)_4]^(2-),which results in the decrease in the resin adsorption capacity for molybdenum.
Ming-Yu WangChang-Jun JiangXue-Wen WangPeng-Fei XianHua-Guang WangYang Yang
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-toaqueous 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.
Ming-Yu WangXue-Wen WangChang-Jun JiangChao-Fan Tao
The adsorption behavior of molybdenum onto D314 was studied with the static adsorption method. The adsorption process was analyzed from thermodynamic and kinetic aspects. The experimental results show that the equilibrium adsorption data conform satisfactorily to the Langmuir equation. In the adsorption process of D314 for molybdenum, the enthalpy change ΔH is positive when temperature is in the range of 298-338 K, which indicates that the adsorption is an endothermic process, and the elevated temperature benefits to the adsorption. Kinetic analysis shows that the adsorption rate is controlled by intraparticle diffusion and chemical diffusion at the same time. The adsorption mechanism of molybdenum onto D314 was discussed based on IR spectra.
为了从焙烧的镍钼矿中提取钼和镍,研究了盐酸浸出-硫酸化焙烧和水浸出处理焙烧后镍钼矿的过程。实验结果表明,焙烧的镍钼矿经过盐酸浸出-硫酸化焙烧然后水浸出后能够获得高的钼和镍浸出率。氧化焙烧的镍钼矿添加0.219 m L/g盐酸(12 mol/L)在液固比为3 m L/g的条件下于65°C浸出30 min;浸出渣添加51.9%浓硫酸在240°C下焙烧1 h;焙砂物料采用已经获得的第一段盐酸浸出液在95°C浸出2 h,钼和镍的总浸出率分别达到95.8%和91.3%。
