[BMIM]Cl/AlCl3离子液体低温电沉积铝过程

采用玻碳/铂为惰性阳极，以1-丁基-3-甲基咪唑氯盐([BMIM]Cl/AlCl₃)离子液体体系为电解液，研究了离子液体电解铝工艺，优化了电解工艺条件，探讨了电解影响因素。结果表明，当电解液[BMIM]Cl∶AlCl₃摩尔比为1∶2.00时，随着温度的升高，铝的沉积槽电压逐渐减小，电流密度增加，但电解液的稳定性减弱，当温度达到90℃时，电解液分解明显。当电解温度一定时，随着[BMIM]Cl∶AlCl₃摩尔比的增加[(1∶1.25)~(1∶2.00)]，电流密度增加。通过赫尔槽实验，SEM、XRD分析了电解铝的沉积形貌和晶相结构。随电流密度的逐渐减小，沉积层变薄，晶相结构变化不大；相同电流密度区随温度的升高，沉积层逐渐变得粗糙。计算了不同槽间距下的槽压与电流密度的关系。

Electrodeposition of aluminum from [BMIM]Cl/AlCl3 ionic liquids at low temperature

Aluminium can be electrodeposited from the ionic liquid 1-butyl-3-methyl imidazole salt chloride ([BMIM]/AlCl₃) below 100℃. It was found that voltage for aluminium deposition decreases with the increase of temperature and the current density increase with the increase of temperature. When the temperature reaches 90℃, the electrolyte become unstable. At a certain temperature, the current density increased gradually with the electrolyte [BMIM]Cl∶AlCl₃ molar ratio changes from 1∶1.25 to 1∶2.00. Effects of current density, temperature on the morphology of Al depositions were studied by Hull cell test. The surface on the cathode is characterized by using scanning electron microscope (SEM) and X-ray diffraction (XRD). Along with the current density decreasing, the electrochemical deposition layers of aluminium become thinner and thinner, but the crystal structure of the aluminium almost no change. Furthermore, the microstructures of deposition aluminium are greatly influenced by temperature. Based on all these investigations, the optimized technological parameters for electrodeposition of aluminum from [BMIM]Cl/AlCl₃ were obtained.