Materials
·
2020
·Vol. 13
·期 17
·3871
·
IF 3.057
Bingbing Wan,Wenfang Li,Wanting Sun,Fangfang Liu,Bin Chen,Shiyao Xu,Weiping Chen,Aihua Yi
Secondary aluminum dross (SAD) is regarded as a solid waste of aluminum recycling process that creates serious environmental and health concerns. However, SAD can also be used as a good source of aluminum, so that utilizing the SAD for the production of valuable products is a promising approach of recycling such waste. In the present work, a novel eco-friendly three-step process was proposed for the synthesis of cryolite (Na3AlF6) from the SAD, and it consisted of (1) water-washing pretreatment of SAD, (2) extraction of Al component via pyro-hydrometallurgy, including low-temperature alkaline smelting, water leaching and purification of leachate in sequence, (3) precipitation of cryolite from the purified NaAlO2solution using the carbonation method. By analysis of the parameter optimization for each procedure, it was found that the maximum hydrolysis efficiency of aluminum nitride (AlN) in the SAD was around 68.3% accompanied with an extraction efficiency of Al reaching 91.5%. On this basis, the cryolite of high quality was synthesized under the following optimal carbonation conditions: reaction temperature of 75 °C, NaAlO2concentration of 0.11 mol/L, F/(6Al) molar ratio of 1.10, and 99.99% CO2gas pressure, and flow rate of 0.2 MPa and 0.5 L/min respectively. The formation of Na3AlF6phase can be detected by XRD. The morphological feature observed by SEM revealed that the as-synthesized cryolite had a polyhedral shape (~1 μm size) with obvious agglomeration. The chemical composition and ignition loss of the as-synthesized cryolite complied well with the requirements of the Chinese national standard (GB/T 4291-2017).
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
HYDROMETALLURGY
·
2022
·
IF 4.217
Jie Tang,Guihua Liu,Tiangui Qi,Qiusheng Zhou,Zhihong Peng,Xiaobin Li,Yilin Wang,Leiting Shen,Jiaping Zhao,HongJie Hao
An understanding of the mechanisms of reactive Al and AlN in a sodium aluminate solution contributes to the safe and effective utilization of secondary aluminum dross (SAD). This study demonstrates that the slurry temperature increased exponentially with an increase in the SAD dosage. Synergistic kinetic phenomena in the form of a large dosage and high temperature occurred initially in relatively stable microbubbles and later in the slurry. The leaching efficiencies of pure Al and AlN powders were greater than that of Al and AlN in SAD, respectively. Meanwhile, the leaching rate became higher for Al in SAD but lower for AlN in SAD compared to that of pure Al and AlN powder. The AlN particles in SAD were covered by Al(OH) 3 precipitated from the saturated solution in the bubbles. As a result, the relatively stable microbubbles with a thick border accelerated the reaction of Al and AlN and produced a saturated solution thereby changing the leaching efficiency and leaching rate of AlN in SAD. The embedded Al and AlN grains in the SAD, relatively stable microbubbles, and the SAD particles covered by Al(OH) 3 , synergistically changed the leaching mechanism. These results provide further understanding of the reaction mechanism of rich bubbles and facilitate the optimization of the comprehensive utilization of SAD.
研究领域:
冶金学
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Cleaner Production
·
2024
·
IF 9.7
Li Cui,Weihong Wang,Xi Chao,Jianming Gao,Fangqin Cheng
The electrolytic aluminum industry generates a large amount lithium (Li)-containing electrolytic aluminum slag (EAS) annually, and this can result in severe environmental pollution and wasting of Li resources. This paper proposes a method for recovering Li from the slag using AlCl 3 as the leaching agent. The effects of the leaching temperature, AlCl 3 concentration, pH, and solid-to-liquid ratio (S/L) on the leaching efficiency of Li + were systematically examined. The structural transformation during the Li leaching process was revealed by SEM, XRD, 27 Al NMR, and XPS analyses. The results indicate that up to 88.3% of Li + can be leached out using 0.85 M of AlCl 3 with an S/L of 1:3 at a leaching temperature of 95 °C and pH of 0.5. The addition of AlCl 3 played an essential role in the decomposition of cryolite/cryolithionite, ultimately resulting in Al–F fracture and Li + release in the leaching solution . Moreover, Al 3+ enters the interior of the slag to participate in the reconstruction of the chiolite with a low NaF/AlF 3 ratio, and reacts with OH − ionized from H 2 O to form hydroxyl aluminum fluoride species. Fluorine ions were solidified in the leaching residues for subsequent cryolite regeneration. This study not only provides an environmentally friendly process for resource utilization from EAS but also reduces the environmental threat caused by the storage of the hazardous waste .
研究领域:
冶金工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Jiamei Xu,Zijian Su,Jicheng Liu,Kun Lin,Yuanbo Zhang
With the improvement of industrial production requirements, the thermal shock resistance (TSR) of the materials used in industrial kilns plays a crucial role in ensuring efficient production. Aluminum-based heat storage ceramic balls (HSCB) are widely used in high-temperature industrial kilns, but they have a problem of weak TSR. A similar situation existed in the HSCB with corundum and Mg-Al spinel phases in our previous research. In this study, corundum-spinel-mullite HSCB was prepared using pre-treated secondary aluminum dross (SAD) as the main material at low roasting temperature. The effects of mullite content on the mechanical properties and microstructure of the HSCB were studied. Mullite whiskers were cross-distributed with corundum and Mg-Al spinel, which benefited the TSR. With the increase of mullite content, the structure of the HSCB gradually became loosely, the TSR increased and then decreased slightly, and linear crack density increased. When mullite content was about 25 %, the comprehensive performance of HSCB performed perfectly. Under the optimal conditions, the coefficient of thermal expansion of the HSCB was only 5.70 × 10 −6 K −1 , the thermal conductivity reached 3.35 W/(m·K) and the TSR was 34 times. This study aimed to provide a theoretical reference for the preparation of aluminum-based ceramic HSCB, as well as to improve the high-value utilization of SAD.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Material Cycles and Waste Management
·
2023
·Vol. 25
·期 4
·2485-2497
·
IF 3.1
Wei Jie,Liu Zhanwei,Yan Hengwei,Yang Wanzhang
Herein, fluorine fixation, nitrogen removal, and the alkaline solution recovery of alumina were studied using calcium-based high-temperature soda roasting. In addition, the effects of roasting conditions, dissolution conditions, and additives (carbon alkali and calcium salt) on fluorine fixation and alumina recovery were studied. The results show that when the roasting temperature was 1100 ℃ and the roasting time was 2 h, the dissolution temperature was 80 °C, while the dissolution time was 20 min. The ratio of soda to dross was 1.0, and 30 wt% CaCO 3 had been added as a fluorine fixing agent. The Al extraction rate from aluminum dross (AD) reached 86.21%, the denitrification rate reached 99.54%, the concentration of soluble fluoride ion was reduced to 0.111 g·L −1 , and the fluoride fixation rate was 75.04 wt%. CaF 2 is the main component of the leaching residue, which can be added as an insulation material for electrolysis. Alkaline oxidation roasting and calcium-based fluoride fixation are effective methods to separate aluminum, fluoride, and nitrogen. This study provides a new method for the safe and efficient utilization of AD.
研究领域:
化学工程
·
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Yunhui Li,Yixiong Chen,Jialin Qing,Zuoying Cao,Shengxi Wu,Qinggang Li,Mingyu Wang,Wenjuan Guan,Guiqing Zhang
The efficient recovery of nickel from chloride systems has long presented a challenge in the field. While solvent extraction is a viable approach, conventional extractants have been associated with drawbacks such as a high requirement for chloride ions and substantial consumption of acids and alkalis. In response to these challenges, this investigation developed and synthesized a novel thiazole-based extractant, N, N-Bis(4-thiazolylmethyl)octylamine (NNBT), tailored for the selective extraction of nickel from chloride systems. Findings from the study indicate that the nitrogen atom situated on the benzylamine framework within NNBT can interact synergistically with the chelating thiazole ring, facilitating effective nickel extraction and notably reducing the need for chloride ions. Furthermore, the extractant can be regenerated using deionized water , thereby obviating the necessity for additional consumption of acids and alkalis. Following the validation of NNBT as an environmentally sustainable and efficient nickel extractant within the chloride ion system, it was successfully employed to selectively and effectively extract nickel from the nickel-aluminum slag of spent HDP catalyst. The extracted nickel and aluminum were subsequently processed into electroplated nickel chloride and polyaluminum chloride, respectively, meeting the national standards of China. These outcomes underscore the eco-friendliness and promise of NNBT for nickel extraction from chloride systems.
研究领域:
冶金工程
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Bin Zhu,Haigang Feng,Xueyuan Zhu,Qiang Jin
As a hazardous waste, secondary aluminum dross (SAD) has troubled the aluminum industry for many years. The inefficient and incomplete hydrolysis of active aluminum components such as AlN, Al 4 C 3 , Al 2 S 3 , AlP in SAD was the main obstacle, which can react with water or even humid air to release toxic, harmful, flammable and odorous gases such as NH 3 , CH 4 , H 2 S, and PH 3 to the environment. In this study, a novel approach to prepare adsorbent was proposed by the deep hydrolysis of active aluminum components from SAD with the aid of grinding activation. High-energy grinding could increase the hydrolysis rate of AlN by ~30% and reduce the apparent activation energy of AlN hydrolysis by ~40 kJ⋅mol −1 in SAD. After grinding-leaching treatment, up to 94.3% AlN, and most of Al 4 C 3 , Al 2 S 3 and AlP were hydrolyzed and transformed into honeycomb boehmite (AlOOH). The leachability of F - , Cl - , NH 4 + , and heavy metals of the treated SAD was evaluated and met the specified requirements for pollution control. Moreover, adsorbent with uniformly covered active γ-alumina was prepared by roasting the harmless product at 600℃ for 2 h. The BET surface area and total pore volume of the as-prepared adsorbent reached 424 m 2 /g and 1.30 cm 3 /g, respectively, and the adsorption capacity of the adsorbent for F - reached 6.40 mg/g. Overall, the novel approach had the advantages of no additives, short process, and simple operation, which was expected to provide deep insights into the harmless treatment and reutilization of SAD.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Minerals Metallurgy and Materials
·
2025
·Vol. 32
·期 5
·1079-1090
·
IF 7.2
Li Xiang,Zhu Nengwu,Xi Yunhao,Li Fei,Zhang Pengfei
Secondary aluminum dross (SAD) is a rich source of recyclable aluminum but poses considerable risk due to its high AlN content. Therefore, thoroughly removing AlN is essential, but intricate aluminum components and expensive additives pose challenges to the process. In this study, waste sodium acetate is proposed as an environmentally friendly additive for completely removing AlN and enhancing the extraction of aluminum from SAD. Through the exothermic decomposition of NaAc, reactions can occur at 850°C. AlN removal efficiency reached 93.19% after sintering, whereas Al leaching efficiency in the subsequent leaching process reached 90.49%, which were 37.86% and 375.26% higher than the removal efficiency of the control, respectively. These favorable results were attributed to the comprehensive transformation of aluminum species. The formation of soluble phase Na 1.95 Al 1.95 Si 0.05 O 4 occurred during the destruction of the Al 2 O 3 layer surrounding AlN and the transformation of other aluminum components. AlN decomposed upon contact with NaAc. Therefore, this study utilizes the decomposition properties of NaAc to provide an efficient and environmentally friendly route for removing AlN and extracting Al from SAD.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2017
·
IF 3.169
Changzai Ren,Wenlong Wang,Guolin Li
Sulfoaluminate cement exhibits a good dimensional stability, an early strength, a high strength, a high resistance to chemical attack (from seawater, sulfates and chlorides), a low energy consumption and low carbon-dioxide emissions during production. However, sulfoaluminate cement factories traditionally use limestone, bauxite and gypsum as materials, which places significant pressure on these natural resources. This study aimed to investigate the feasibility of substituting traditional raw materials with industrial solid wastes in sulfoaluminate clinker production. It was achieved by sintering a mixture of industrial solid wastes (coal gangue: 8%–15%, flue gas desulfurization gypsum: 25%–35%, aluminum slag: 30%–35%, carbide slag: 30%–35%) at 1150–1300 °C. The mineralogical composition of the clinker was C 4 A 3 S ‾ , C 2 S and C 4 AF. The compressive strength of hydrated specimens reached as high as 75 MPa after a 28 d curing. This research provides a feasible and promising way to produce high-value products using industrial solid wastes and may promote their large-scale utilization.
研究领域:
建筑材料
·
环境科学
·
资源循环利用
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Siyuan Zhu,Jun Ke,Zhongnan Chen,Zhaoyang Yan,Lulu Zhao,Xinhong Qiu
Secondary aluminum dross (SAD) as a hazardous waste has been widely studied on recycling by acid leaching process, but residues accounting for approximately 50 wt% of SAD are still produced and rarely reused. In this study, residues from secondary aluminum dross are retrieved to fabricate Fe-based acidized aluminum ash sludge (FAS) heterojunction catalyst for photocatalytic degrading tetracycline hydrochloride under visible light, which does not only reduce resource utilization cost of SAD, but also realize efficient wastewater treatment by clean photocatalytic technique. Firstly, acidized sludge was obtained from SAD via an acid leaching and then utilized to fabricate FAS by calcination method. From the results of characterizations, BaFeO 3-x and Fe 2 O 3 were demonstrated to be deposited on the surface of acidized sludge, resulting in the successful formation of FAS heterojunction catalyst. As a result, the FAS exhibits an excellent performance in the removal of tetracycline hydrochloride (TCH), reaching to 92.2 % within 150 min under dark adsorption and visible light excitation. To further broaden the application of FAS in actual circumstance, the degradation of mixed dye in wastewater and actual medical wastewater were conducted over the optimal sample of FAS. After four cycles, the removal ability remained at 86.0 %, which shows the exceptional stability.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Yuanbo Zhang,Jiamei Xu,Jicheng Liu,Kun Lin,Zijian Su
Secondary aluminum dross (SAD) is a kind of hazardous waste with high aluminum content produced in the aluminum industry. From another point, SAD is also considered as a valuable aluminum resource, which can be used as high-quality raw material for value-added products such as refractory materials . In this study, a novel route for preparing corundum-spinel heat storage spheres (HSS) using washed residue of secondary aluminum dross (WSAD) as the main raw material was proposed. FactSage 8.1 software was used for the detailed thermodynamic calculation, which provided accurate theoretical guidance for the actual synthesis experiments. The effects of roasting temperature and formula on the main phases, compressive strength , porosity, and bulk density of HSS were systematically analyzed. The strengthening mechanism of the liquid phase on the sintering strength was revealed. The results showed that the HSS with good properties could be obtained with 90 wt% WSAD, 10 wt% kaolin, and 1 wt% bentonite. The HSS mainly consisted of corundum and spinel phases. The synthetic temperature of corundum-spinel ceramic was reduced by more than 200 °C. This study provides a novel way for value-added utilization of SAD as well as realizing the deep detoxification and the removal of nitrogen of it.
研究领域:
材料科学
·
环境工程
·
冶金工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）