[AlO4Al12(OH)24(H2O)12]7+ (Al13) formation in electrolysis process is studied. The results detected by27Al NMR spectroscopy show that high content of Al13 polymer is formed in the partially hydrolyzed aluminum solutio...[AlO4Al12(OH)24(H2O)12]7+ (Al13) formation in electrolysis process is studied. The results detected by27Al NMR spectroscopy show that high content of Al13 polymer is formed in the partially hydrolyzed aluminum solution prepared by controlled electrolysis process. In the produced electrolyte of total Al concentration ([AlT]) 2.0 mol · L?1 with a basicity (B = OH/Al molar ratios) of 2.0, the content of Al13 polymer is over 60% of total Al. Dynamic light scattering shows that the size distribution of the final electrolyte solutions ([AlT] = 2.0 mol · L?1) is trimodal with B = 2.0 and bimodal with B = 2.5. The aggregates of Al13 complexes increase the particle size of partially hydrolyzed aluminum solution.展开更多
The ocean poly-metallic nodule was leached by using slurry electrolysis process in HCl-NaCl medium.The leaching rates of Mn,Co,Cu and Ni in the ocean poly-metallic nodule are all above 97%.Meanwhile,the high purity of...The ocean poly-metallic nodule was leached by using slurry electrolysis process in HCl-NaCl medium.The leaching rates of Mn,Co,Cu and Ni in the ocean poly-metallic nodule are all above 97%.Meanwhile,the high purity of electrolytic MnO2 is also obtained as an anode product.The effects of electrolysis electric quantity,acidity,temperature,slurry density,grain size and iron ions concentration were studied.The results show that the ocean poly-metallic nodule can be treated economically in the slurry electrolysis process.展开更多
Al-Cu-Y alloys were prepared by molten salt electrolysis in fluoride-oxide system composed of electrolyte（Na3 AlF6-AlF3-LiF-MgF2） and oxide（Al2 O3-CuO-Y2 O3）. Cathodic reduction process of Al2 O3,CuO and Y2 O3 wer...Al-Cu-Y alloys were prepared by molten salt electrolysis in fluoride-oxide system composed of electrolyte（Na3 AlF6-AlF3-LiF-MgF2） and oxide（Al2 O3-CuO-Y2 O3）. Cathodic reduction process of Al2 O3,CuO and Y2 O3 were analyzed by cyclic voltammetry and chronoamperometry. Components and phase composition of alloy samples prepared by potentiostatic electrolysis were characterized by scanning electron microscopy and energy dispersive spectroscopy. The results show that the Al-Cu-Y alloy can be prepared in the AIF3-NaF-5 wt%LiF-5 wt%MgF2（NaF/AlF3 = 2.2, molecular ratio） eutectic system with mixed oxide（Al2 O3-CuO-Y2 O3） through 2 h at the conditions of a temperature of 1208 K, cell voltage3.0 V, cathode current density 0.7 A/cm^2. Al（Ⅲ） and Cu（Ⅱ） ions can be reduced to zero valence Al（0） and Cu（0） directly on carbonaceous electrode surface by instantaneous nucleation, respectively, the reduction process is controlled by diffusion. The reduction potential of Y（Ⅲ） ions is close to the active ions of fluoride melts, but strengthened phase AI3 Y can be formed through electrochemical reduction and alloyed process with active Al（Ⅲ） and Cu（Ⅱ） ions, meanwhile, the Al2 Cu and Al3 Y phases are distributed at the grain boundary of Al matrix.展开更多
基金This work was supported by the National Natural Science Foundation of China (Grant No. 50108016).
文摘[AlO4Al12(OH)24(H2O)12]7+ (Al13) formation in electrolysis process is studied. The results detected by27Al NMR spectroscopy show that high content of Al13 polymer is formed in the partially hydrolyzed aluminum solution prepared by controlled electrolysis process. In the produced electrolyte of total Al concentration ([AlT]) 2.0 mol · L?1 with a basicity (B = OH/Al molar ratios) of 2.0, the content of Al13 polymer is over 60% of total Al. Dynamic light scattering shows that the size distribution of the final electrolyte solutions ([AlT] = 2.0 mol · L?1) is trimodal with B = 2.0 and bimodal with B = 2.5. The aggregates of Al13 complexes increase the particle size of partially hydrolyzed aluminum solution.
基金Projects(50674014,50734005)supported by the National Natural Science Foundation of China
文摘The ocean poly-metallic nodule was leached by using slurry electrolysis process in HCl-NaCl medium.The leaching rates of Mn,Co,Cu and Ni in the ocean poly-metallic nodule are all above 97%.Meanwhile,the high purity of electrolytic MnO2 is also obtained as an anode product.The effects of electrolysis electric quantity,acidity,temperature,slurry density,grain size and iron ions concentration were studied.The results show that the ocean poly-metallic nodule can be treated economically in the slurry electrolysis process.
基金Project supported by the National Natural Science Foundation of China(51564015)
文摘Al-Cu-Y alloys were prepared by molten salt electrolysis in fluoride-oxide system composed of electrolyte（Na3 AlF6-AlF3-LiF-MgF2） and oxide（Al2 O3-CuO-Y2 O3）. Cathodic reduction process of Al2 O3,CuO and Y2 O3 were analyzed by cyclic voltammetry and chronoamperometry. Components and phase composition of alloy samples prepared by potentiostatic electrolysis were characterized by scanning electron microscopy and energy dispersive spectroscopy. The results show that the Al-Cu-Y alloy can be prepared in the AIF3-NaF-5 wt%LiF-5 wt%MgF2（NaF/AlF3 = 2.2, molecular ratio） eutectic system with mixed oxide（Al2 O3-CuO-Y2 O3） through 2 h at the conditions of a temperature of 1208 K, cell voltage3.0 V, cathode current density 0.7 A/cm^2. Al（Ⅲ） and Cu（Ⅱ） ions can be reduced to zero valence Al（0） and Cu（0） directly on carbonaceous electrode surface by instantaneous nucleation, respectively, the reduction process is controlled by diffusion. The reduction potential of Y（Ⅲ） ions is close to the active ions of fluoride melts, but strengthened phase AI3 Y can be formed through electrochemical reduction and alloyed process with active Al（Ⅲ） and Cu（Ⅱ） ions, meanwhile, the Al2 Cu and Al3 Y phases are distributed at the grain boundary of Al matrix.
