An novel method on preparation of precursor solution for solvent separation of molybdenum (Mo) and tungsten (W) by hydrogen peroxide (H2O2)-complexation from the ammonium tungstate solution containing high Mo wa...An novel method on preparation of precursor solution for solvent separation of molybdenum (Mo) and tungsten (W) by hydrogen peroxide (H2O2)-complexation from the ammonium tungstate solution containing high Mo was studied. The precursor solution was obtained via evaporation deamination and H202-complex transformation processes. Then it was extracted with a mixture extractant of tri-alkyl phosphine oxide (TRPO) and tributyl phosphate (TBP) to separate Mo and W. The results indicated that the evaporation deamination complex method reduced the acid consumption by more than 90% in comparison with the traditional directly acid regulation complex method. The transformation rates of W and Mo were higher than 95% and the decomposition rate of H202 was less than 15% at a 1.8-1.9 times H202 dosage, 45-50 ℃, initial pH of 1.80-1.90, and transformation volume ratio of 100% for 60 min in the H2O2-complexation transformation process. The minimum extraction rate of W was 2%, the maximum extraction rate of Mo was 82.6% and the highest separation coefficient was 76.7 in a single-stage extraction.展开更多
The removal of tungsten(W)and vanadium(V)from molybdate solutions was studied using the poly hydroxyl chelating resin D403in batch and column experiments.The batch experiments indicated that tungsten and vanadium coul...The removal of tungsten(W)and vanadium(V)from molybdate solutions was studied using the poly hydroxyl chelating resin D403in batch and column experiments.The batch experiments indicated that tungsten and vanadium could be preferentially adsorbed by the D403resin for4h in molybdate solution at a pH of approximately9.25.Separation factors,αVMo andαWMo,wereabove45and18,respectively,when the molar ratios of Mo/V and Mo/W in the solution exceeded40.Elution tests illustrated that vanadium and tungsten could be easily eluted from the resin with1mol/L sodium hydroxide solution in only1h.To further explore the sorption mechanism of the resin,the experimental equilibrium isotherm data of the three metals fitted well with the Freundlich model.The column experiments confirmed the adaptability of the D403resin in the production of sodium molybdate with a removal rate of tungsten surpassing90%and that of vanadium of99.4%.展开更多
基金Project(2010ZX07212-008) supported by the Major Science and Technology Program for Water Pollution Control and Treatment the China Molybdenum Co., Ltd.for financial support
文摘An novel method on preparation of precursor solution for solvent separation of molybdenum (Mo) and tungsten (W) by hydrogen peroxide (H2O2)-complexation from the ammonium tungstate solution containing high Mo was studied. The precursor solution was obtained via evaporation deamination and H202-complex transformation processes. Then it was extracted with a mixture extractant of tri-alkyl phosphine oxide (TRPO) and tributyl phosphate (TBP) to separate Mo and W. The results indicated that the evaporation deamination complex method reduced the acid consumption by more than 90% in comparison with the traditional directly acid regulation complex method. The transformation rates of W and Mo were higher than 95% and the decomposition rate of H202 was less than 15% at a 1.8-1.9 times H202 dosage, 45-50 ℃, initial pH of 1.80-1.90, and transformation volume ratio of 100% for 60 min in the H2O2-complexation transformation process. The minimum extraction rate of W was 2%, the maximum extraction rate of Mo was 82.6% and the highest separation coefficient was 76.7 in a single-stage extraction.
基金Project(2014CB643405)supported by the National Basic Research Program of China
文摘The removal of tungsten(W)and vanadium(V)from molybdate solutions was studied using the poly hydroxyl chelating resin D403in batch and column experiments.The batch experiments indicated that tungsten and vanadium could be preferentially adsorbed by the D403resin for4h in molybdate solution at a pH of approximately9.25.Separation factors,αVMo andαWMo,wereabove45and18,respectively,when the molar ratios of Mo/V and Mo/W in the solution exceeded40.Elution tests illustrated that vanadium and tungsten could be easily eluted from the resin with1mol/L sodium hydroxide solution in only1h.To further explore the sorption mechanism of the resin,the experimental equilibrium isotherm data of the three metals fitted well with the Freundlich model.The column experiments confirmed the adaptability of the D403resin in the production of sodium molybdate with a removal rate of tungsten surpassing90%and that of vanadium of99.4%.