Min Li,Bingliang Gao,Chengyuan Liu,Wenting Chen,Zhongning Shi,Xianwei Hu,Zhaowen Wang
A new acetamide based eutectic solvent is obtained via complexation with AlCl 3 . The electrodeposition of aluminum is successfully achieved from AlCl 3 /acetamide eutectic solvent. The cyclic voltammograms on tungsten electrode indicate that Al(III) are easier to be reduced from AlCl 3 /acetamide eutectic solvent at a molar ratio in a range of 1.1 to 1.5. Aluminum coatings were prepared at −0.25 V (vs. Al/Al 3+ ) and different temperatures at 313 K and 333 K in AlCl 3 /acetamide eutectic solvent at molar ratio = 1.3 (r = 1.3). The SEM images show that thick adherent aluminum films were deposited on the copper substrate. The EDS and XRD analysis confirm that the obtained deposits are pure aluminum. The present results allowed the new and cheap AlCl 3 /acetamide eutectic solvent to be a potential electrolyte for aluminum electrodeposition at room temperature .
Buju Guo,Yaowu Wang,Yuyao Huang,Jianping Peng,Yuezhong Di,Chang Wang,Ke Wang
The amount of scrap aluminum has increased continuously in recent years such that the widely adopted method of remelting no longer meets the demands of high-quality recycled secondary aluminum. Molten salt electrolysis is a method of upcycling scrap aluminum to pure aluminum. In this study, pure aluminum was recovered from scrap aluminum through the electrolysis of a 56 mol%LiCl-36 mol%KCl-8 mol%NaCl molten salt system. The electrochemical dissolution behavior of scrap aluminum was studied adopting an anodic polarization curve. The results show that Al dissolved preferentially compared with Si and Fe in scrap aluminum. The effects of electrolysis parameters, such as the AlCl 3 concentration, electrolysis temperature, and current density, on the current efficiency and cathode products were studied along with the process of purifying scrap aluminum. The results show that the adoption of a suitable current density, electrolysis temperature and AlCl 3 concentration increases the current efficiency and improves the morphology of the cathode products. Pure aluminum of industrial grade with purity of 99.8 % can be obtained on the cathode at an electrolysis temperature of 550 °C, AlCl 3 concentration of 10 mol%, electrolysis time of 3 h, and current density controlled below 0.15 A/cm 2 .
Electrolytic recovery of pure aluminum is a conventional method for the recycling of waste aluminum alloys, which is very important to economic development and environmental protection. However, the conventional electrolytic recovery process suffers from several inherent problems, which restricts the further development of this technology. In this study, an air- and moisture-stable 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ionic liquid was applied in the dissolution of aluminum chloride. The upper phase of the resulting mixture was used as a low-temperature electrolyte in the electrolytic recovery of pure aluminum. The results of cyclic voltammetry and linear sweep voltammetry showed that aluminum could be electrodeposited from the electrolyte and that the main impurity elements of the aluminum alloy could also be stripped off by the electrolytic method. Based on these measurements, the electrolytic recovery process was conducted at 0.2−0.6 V and 303.2−373.2 K. Scanning electron microscope micrographs showed that smooth, compact and well-adherent deposits were obtained at 0.4 V from 303.2 to 323.2 K. In this situation, the preferred crystallographic orientation of these deposits was the (200) plane. Meanwhile, the mass content of aluminum in all deposits was higher than 99.6% according to the purity characterization. This study may be useful for the further application of ionic liquids in the low-temperature recycling of waste aluminum alloys.
Buju Guo,Yaowu Wang,Ruoyu Li,Yifei Li,Boxiong Zhang,Jianping Peng,Yuezhong Di,Ke Wang,Chang Wang
Scrap aluminum (Al) alloy recycling is critical for energy conservation and decreasing carbon emissions. Conventional remelting process does not remove alloying elements, severely limiting the value and applications of recycled Al. To overcome this limitation, this study develops an efficient process for recovering pure Al from scrap Al alloys via soluble anode electrolysis in a designed MgCl 2 -KCl-NaCl (MKN) molten salt system. Real-time monitoring of the electrolysis process, time-dependent characterization of cathodic deposits, and electrochemical analyses reveal a three-stage cathodic deposition mechanism in the MKN molten salt system: initial underpotential deposition of Mg 2+ transitions to co-deposition of Mg 2+ and Al 3+ , and ultimately to exclusive reduction of Al 3+ , which is driven by progressive Al 3+ accumulation. The introduction of AlCl 3 proves pivotal, simultaneously enhancing Al 3+ deposition efficiency while effectively suppressing Mg 2+ co-reduction. Systematic optimization identifies 12.5 wt% AlCl 3 addition, 500 °C, and 0.15 A/cm 2 as the ideal operational parameters, achieving recycled Al with 99.84 wt% purity. The soluble anode electrolysis process in the MKN molten salt system represents an efficient and scalable alternative to conventional remelting. The developed process is capable of producing recycled Al with purity comparable to that of primary Al while addressing critical sustainability challenges in the Al industry.
危险品化学品经营许可证（带存储）