Study On The Dynamic Separation Of Molybdenum And Rhenium By Macroporous Resin

Rhenium is a kind of rare metal element with high melting point, high boiling point and high density. The content of the rhenium in the nature is very little, and we has not found the natural existence rhenium’s independent mineral so far. The rhenium mainly scattered in molybdenite and bornite whose refining dust is the main material to prepare the rhenium. Recovering rhenium from the calcinations fume of molybdenum, which realizes the complex using rate of the resource increases the income of the corporations and effetely decreases the pollution of fume of molybdenum, has the important economical, environmental and social profits.The leaching conditions of fume of molybdenum and the separating condition by D-314 are studied .The concentration of Molybdenum and rhenium are respectively determined by the thiocyanate direct spectrophotometry and kinetic- specatrophotometry. According to the properties that rhenium and molybdenum can be exchanged to the ion-exchange resin under certain conditions, and desorbed by different desorption agents, we can achieve the purpose of separating molybdenum and rhenium.The results show that: the sample was leached by sulphuric acid, the mass concentration of molybdenum is 19.6%, RSD = 2.79 (n=4) and the mass concentration of rhenium is 0.0115%, RSD = 7.01 (n=6).The leaching congdtions: sulphuric acid concentration: 1.64 mol/L, time: 1.5 hour, solution and solid:10,temperater:60℃are determined by the orthogonality experiment. In room temperature, molybdenum and rhenium can be effectively absorbed at pH=7.0 at the flow rate of 1.0 mL/m in the column. 2.0%NH3·H2O+2.0%NH4NO3 mixture solution is chosen as the molybdenum desorption solution at the flow rate of 4.0 mL/min with 16.5 mL; 6.0%NH3·H2O is chosen as the rhenium desorption solution at the flow rate of 2.0 mL/min with 13.0 mL. The separation coefficient KMo/Re = 383, the recoveries of molybdenum and rhenium are 85.80% and 81.02%. The recovery of molybdenum in the leaching solution of calcinations fume of molybdenum is 97.32%, the concentration of rhenium in the desorption solution is 1.42μg/mL .The leaching solution of calcinations fume of molybdenum can be separated by D-314 after pre-disposing.The desorption solution of molybdenum was made to ammomium dodecamolybdate:(NH4)2 Mo12MoO40.6H2O by the method of nitric acid deposition the purity is 98.78%.The desorption solution of rhenium was made to potassium perhenate by the method of potassium chloride deposition, the purity is 3.62%. The results of XRD and ICP-MS show that: the impurities in ammomium dodecamolybdate are Na (0.05%) and Zn (3.54%), the impurities in potassium perhenate are Na (0.03%) and Zn (3.47%).