Study On The Process Of Copper Restores The Salt Of Molybdenum

In the process smelting in tungsten and molybdenum, separation of tungsten and molybdenum is a technical problem urgent to solve, is an important part to ensure sustainable development of tungsten and molybdenum industry. Based on the comprehensive analysis of existing research results of tungsten and molybdenum separation, and according to different electrochemical properties of tungsten and molybdenum, reduction behavior of tungsten and molybdenum is studied when copper is used as a reducing agent.The main contents:(1) Mo-H₂O Potential-pH diagram, W-H₂O Potential-pH diagram and Mo (Cu)-H₂O Potential-pH diagram was studied, which provides a theoretical guidance for this research of article.(2) The dynamics process of the copper selective reduction of acid radical of molybdate has been studied. Th nitial rate method is applied to test the reaction order, the results show that the selective reduction of molybdenum on copper is 0.68 H, and Mo is 0.89;and the relationship between rate and reaction temperature has been studied, which has measured activation energy 76.37KJ·mol^-1at 30℃; exploration of the copper selective reduction reaction mechanism of molybdenum has been studied, the result show that reduction process is controlled by the chemical reaction.(3) Researched the influence of acidity, reaction time, the dosage of EDTA, and the temperature which if have the complex condition of EDTA for the reduction rate of molybdenum. The results show that the reduction rate of the molybdenum declined with using complexing agent; but if without complexing agent, just controlled the pH of the system less than 2, it didn't engender the sediment of cupric tungstate and molybdate;the reductive reaction need the condition with high acid system.(4) The characteristic of reductive product of molybdenum and its alkaline hydrolysis test were studied.The result shows that reductive product is a homogeneous crystal with hexagonal column; the valence state of molybdenum is +5.72;under the room temperature the time of the alkaline hydrolysis about 2 hours, the dosage of alkali is 1.2 times than theoretical,and the rate of the alkaline hydrolysis can achieve above 97.8%; the process of the reaction mechanism for alkaline hydrolysis is the molybdenum of reducing state is prior oxidated under the alkali condition , a part of copper ion is restored ,and generated molybdate,copper powder and copper hydroxide.