Sodium hypochlorite was used to treat the standard molybdenum concentrates; the oxidization conditions for sodium hypochlorite were investigated, and the electro-oxidation process was performed. The results indicate t...Sodium hypochlorite was used to treat the standard molybdenum concentrates; the oxidization conditions for sodium hypochlorite were investigated, and the electro-oxidation process was performed. The results indicate that in the suitable conditions, such as temperature around 25℃, NaCl concentration 4.0mol/L, mass ratio of ore slurry liquid to solid （mL/mS） 20, electric charge per gram Mo 0.522C, pH value of original slurry 8, anodic current density 700A·m-2 （cell potential 2.72.9V）, the Mo leaching rate and the current efficiency reach 98% and 36%, respectively. In order to overcome some shortages of the electro-oxidation process, such as low current efficiency, low Mo concentration in the leaching solution, ultrasonic was adopted to intensify the leaching process. The results show that the Mo leaching rate exceeds 98%, current efficiency increases from 36% to 50% and the Mo concentration in the leaching solution reaches about 60g/L at low mL/mS of 8 and low electric charge of 0.373C.展开更多
In order to utilize the chemical energy in hydrometallurgical process of sulfide minerals reasonably and to simplify the purifying process, the electrogenerative process was applied and a dual cell system was introduc...In order to utilize the chemical energy in hydrometallurgical process of sulfide minerals reasonably and to simplify the purifying process, the electrogenerative process was applied and a dual cell system was introduced to investigate FeCl3 leaching of nickel sulfide concentrate. Some factors influencing the electrogenerative leaching, such as electrode structure, temperature and solution concentration were studied. The results show that a certain quantity of electrical energy accompanied with the leached products can be acquired in the electrogenerative leaching process. The output current and power increase with the addition of acetylene black to the electrode. Varying the components of electrode just affects the polarization degree of anode. Increasing FeCl3 concentration results in a sharp increase in the output of the leaching cell when c（FeCl3） is less than 0.1 mol/L. The optimum value of NaCl concentration for electrogenerative leaching nickel sulfide concentrate with FeCl3 is 3.0 mol/L. Temperature influences electrogenerative leaching by affecting anodic and cathodic polarization simultaneously. The apparent activation energy is determined to be 34.63 kJ/mol in the range of 298 K to 322 K. The leaching rate of Ni2+ is 29.3% after FeCl3 electrogenerative leaching of nickel sulfide concentrate for 620 min with a filter bag electrode.展开更多
Simultaneous equilibrium was applied to the thermodynamic analysis and calculation of Bi（Ⅲ）-X（Cl-, NO-3）-H2O systems, based on which the diagrams of the logarithm of equilibrium concentration of Bi（Ⅲ） of serie...Simultaneous equilibrium was applied to the thermodynamic analysis and calculation of Bi（Ⅲ）-X（Cl-, NO-3）-H2O systems, based on which the diagrams of the logarithm of equilibrium concentration of Bi（Ⅲ） of series precipitation vs pH value of these two systems at 25 ℃ were obtained, and the pH ranges of the stable zones of various precipitations were analyzed and determined. In Bi（Ⅲ）-Cl--H2O system, the variations of c0(Bi3+) and （c0（Cl-）） have little effect on the equilibria of Bi（OH）3-solution and BiOOH-solution, but has great influence on the （equilibrium） of BiOCl-solution. However, in Bi（Ⅲ）-NO-3-H2O system, the variations of c0(Bi3+) and c0（NO-3） have little effect on equilibria of Bi（OH）3-solution, BiOOH-solution and Bi2O3-solution. When pH value is high, Bi2O3 is the thermodynamic stable phase, its stable zone is the widest, almost including the stable zones of BiOCl or （BiONO3,） （Bi（OH）3） and BiOOH. Bi（OH）3 cannot be obtained from Bi（Ⅲ）-Cl--H2O system, even strong alkaline media. Bi2O3 can be obtained from the solution directly, and highly pure BiOCl or BiONO3 can also be obtained through strictly controlling pH value.展开更多
文摘Sodium hypochlorite was used to treat the standard molybdenum concentrates; the oxidization conditions for sodium hypochlorite were investigated, and the electro-oxidation process was performed. The results indicate that in the suitable conditions, such as temperature around 25℃, NaCl concentration 4.0mol/L, mass ratio of ore slurry liquid to solid （mL/mS） 20, electric charge per gram Mo 0.522C, pH value of original slurry 8, anodic current density 700A·m-2 （cell potential 2.72.9V）, the Mo leaching rate and the current efficiency reach 98% and 36%, respectively. In order to overcome some shortages of the electro-oxidation process, such as low current efficiency, low Mo concentration in the leaching solution, ultrasonic was adopted to intensify the leaching process. The results show that the Mo leaching rate exceeds 98%, current efficiency increases from 36% to 50% and the Mo concentration in the leaching solution reaches about 60g/L at low mL/mS of 8 and low electric charge of 0.373C.
文摘In order to utilize the chemical energy in hydrometallurgical process of sulfide minerals reasonably and to simplify the purifying process, the electrogenerative process was applied and a dual cell system was introduced to investigate FeCl3 leaching of nickel sulfide concentrate. Some factors influencing the electrogenerative leaching, such as electrode structure, temperature and solution concentration were studied. The results show that a certain quantity of electrical energy accompanied with the leached products can be acquired in the electrogenerative leaching process. The output current and power increase with the addition of acetylene black to the electrode. Varying the components of electrode just affects the polarization degree of anode. Increasing FeCl3 concentration results in a sharp increase in the output of the leaching cell when c（FeCl3） is less than 0.1 mol/L. The optimum value of NaCl concentration for electrogenerative leaching nickel sulfide concentrate with FeCl3 is 3.0 mol/L. Temperature influences electrogenerative leaching by affecting anodic and cathodic polarization simultaneously. The apparent activation energy is determined to be 34.63 kJ/mol in the range of 298 K to 322 K. The leaching rate of Ni2+ is 29.3% after FeCl3 electrogenerative leaching of nickel sulfide concentrate for 620 min with a filter bag electrode.
文摘Simultaneous equilibrium was applied to the thermodynamic analysis and calculation of Bi（Ⅲ）-X（Cl-, NO-3）-H2O systems, based on which the diagrams of the logarithm of equilibrium concentration of Bi（Ⅲ） of series precipitation vs pH value of these two systems at 25 ℃ were obtained, and the pH ranges of the stable zones of various precipitations were analyzed and determined. In Bi（Ⅲ）-Cl--H2O system, the variations of c0(Bi3+) and （c0（Cl-）） have little effect on the equilibria of Bi（OH）3-solution and BiOOH-solution, but has great influence on the （equilibrium） of BiOCl-solution. However, in Bi（Ⅲ）-NO-3-H2O system, the variations of c0(Bi3+) and c0（NO-3） have little effect on equilibria of Bi（OH）3-solution, BiOOH-solution and Bi2O3-solution. When pH value is high, Bi2O3 is the thermodynamic stable phase, its stable zone is the widest, almost including the stable zones of BiOCl or （BiONO3,） （Bi（OH）3） and BiOOH. Bi（OH）3 cannot be obtained from Bi（Ⅲ）-Cl--H2O system, even strong alkaline media. Bi2O3 can be obtained from the solution directly, and highly pure BiOCl or BiONO3 can also be obtained through strictly controlling pH value.
