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
JOM
·
2023
·Vol. 76
·期 3
·1467-1476
·
IF 2.6
Xia Chengcheng,Liu Zhanwei,Yan Hengwei,Liu Qiang,Li Mengnan,Lan Jinghao
Spent anodes (butts) are the remaining portion of prebaked anodes after consumption, which are reintroduced into the production of prebaked anodes after treatment. Among these residues, the main harmful element, sodium, tends to accumulate with the repeated recycling of the butts. This accumulation increases the air reactivity of prebaked anodes and consequently reduces their quality. In this study, aluminum sulfate hydrothermal acid leaching was used to remove sodium from the butts. The effects of leaching temperature, Al 3+ concentration, leaching time, and liquid-to-solid ratio on the removal of sodium from the butts were investigated. The sodium removal rate reached 99.42% at a leaching temperature of 90°C, an Al 3+ concentration of 1.5 mol/L, a leaching time of 2.5 h, and a liquid-to-solid ratio of 25 mL/g. This method significantly reduced the sodium content in the butts, offering a new approach for the high-quality recovery of the butts.
研究领域:
冶金工程
·
环境科学
✓ 已验证
DOI
高影响因子
Journal of Energetic Materials
·
2022
·
IF 2.421
Dongyu Hao,Yinghui Hu,Fang Wang,Debin Xia,Dakang Wang,Ruiqing Fan,Yulin Yang,Kaifeng Lin
In this work, a novel Al2O3-free core-shell structured nAl@aluminum-perfluorooctanoate (F-x) nanocomposite has been prepared via a self-assembly approach. The Al2O3 shell was first removed by hydrofluoric acid (HF) solution, and then the perfluorooctanoic acid (PFOA) was coated on the surface of nAl by a self-assemble reaction. The thickness of the obtained F-x layer can be easily tuned by using different amount of PFOA based on the chemical interaction between nAl and PFOA molecules. The obtained nAl@F-x nanocomposite showed an enhanced exothermic and combustion performance due to the synergetic effect between F-x and nAl and the mesoporous structure in situ formed during the combustion process. This work demonstrated that nAl@F-x nanocomposite prepared by PFOA coating on nAl could effectively solve the detrimental effect of in situ formed Al2O3, thus enhancing the combustion and thermal reaction performances, which showed great potential to be applied in solid rocket propellant.
研究领域:
材料科学
·
燃烧与推进
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Communications
·
2023
·
IF 3.8
Jiaming Li,Youjian Yang,Wenju Tao,Zhaowen Wang,Jiangyu Yu,Jiaxin Yang,Zhibo Liu
As China's aluminum electrolysis industry expanded its production capacity, it produced a large amount of bath materials– cryolite based molten salt, which is not utilized fast enough and piled up in aluminum factories. It is of great significance to find a proper way to process the accumulated bath materials. Through the method introduced in this paper, aluminum fluoride can be produced from cryolite-based electrolyte and fed back into the aluminum electrolysis cell as a necessary additive. This method includes four steps: Calcination of crystalline aluminum nitrate with cryolite. Cryolite and crystalline aluminum nitrate are mixed and preheated. The main chemical reaction that occurs in this step will produce sodium nitrate (NaNO 3 ), β-aluminum fluoride (β-AlF 3 ), chiolite (Na 5 Al 3 F 14 ) and the aluminum hydroxyfluoride hydrate (AHF). After calcination, the products are washed with water to separate soluble NaNO 3 from the other products. The insoluble products obtained after washing are calcined with ammonium bifluoride to convert AHF into AlF 3 . The mixture obtained after preheating is then washed with an aqueous solution of aluminum salt (such as Al(NO 3 ) 3 ) to remove Na 5 Al 3 F 14 . Aluminum fluoride of high purity is obtained in the end. Calcination step is the most important among the four steps. The effects of calcination temperature (85 – 135 ℃) and molar ratio of crystalline aluminum nitrate to cryolite (0.5 – 2) on the conversion rate of cryolite were studied. The experimental results show that the highest conversion rate of cryolite can reach 97.03%. Through SEM, EDS , ICP and other analysis methods, it was found the final products contained more than 98.8 wt% aluminum fluoride and less than 0.4 wt% sodium, and the average particle size of aluminum fluoride is approximately 15 – 20 µm.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Yongyang Zhu,Liming Zeng,Daifeng Wu,Renheng Tang,Qing Zhou
The lack of cost-effective regeneration techniques for LiBH 4 limits its large-scale applications for supplying hydrogen via hydrolysis. Now, we report a facile method to regenerate LiBH 4 by ball milling its real hydrolytic byproduct (LiBO 2 · x H 2 O) with cheap Al based reducing agents, instead of traditional Mg. Effective strategies are developed to promote the formation of LiBH 4 by introducing Li 2 O to enable the dense Al 2 O 3 to convert into LiAlO 2 on Al surface and break up passivation layers, and by partially replacing Al with Al-RE alloy to improve grinding and contacting efficiency of raw materials and facilitate the conversion from initial H + in LiBO 2 ·2H 2 O to final H ¯ in LiBH 4 . A yield of 10.4 % can be obtained for a relatively short ball milling time (10 h) for the Al-Al 2 Ce-Li 2 O-LiBO 2 ·2H 2 O system. Another advantage of this method is that the utilization of H + source in LiBO 2 ·2H 2 O improves energy efficiency and reduces the cost. This work broadens the species of reducing agents for borohydride regeneration and enriches its regeneration methods.
研究领域:
材料科学
·
化学工程
·
氢气储存
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Zhenhao Yang,Guihua Liu,Tiangui Qi,Qiusheng Zhou,Zhihong Peng,Leiting Shen,Yilin Wang,Xiaobin Li
The quality of alumina ceramics generally depends on alumina powder. High-density alumina ceramics were prepared from industrial coarse gibbsite. Near-spheric α-Al 2 O 3 with particles smaller than 500 nm was produced via the synergy of B and F from NH 4 BF 4 . The near-spheric α-Al 2 O 3 calcined at low temperature generated alumina ceramics with high density and low porosity. Meanwhile, the wet pretreatment yielded smaller particles with structural distortion and high microstrain and aluminum hydroxide, notably increasing the relative density of alumina ceramics. 99.18 % relative density, 0.017 % porosity, and 27.54 GPa Vickers hardness of alumina ceramics were achieved at 1650 °C for 2 h without additives and pressed sintering. In addition, the early stage of sintering of alumina green body followed particle boundary diffusion with reduced activation energy in the sintering process. The close packing of the spheric α-Al 2 O 3 , high microstrain of α-Al 2 O 3 , structural defects with considerable AlO 4 units calcined at low temperature, structural distortion in the alumina, and activated alumina on the α-Al 2 O 3 surface collectively promoted the densification of alumina ceramics, achieving remarkable hardness, high density, and tiny porosity.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
·
2016
·Vol. 21
·期 2
·469-476
·
IF 2.327
Li Min,Gao Bingliang,Liu Chengyuan,Chen Wenting,Wang Zhaowen,Shi Zhongning,Hu Xianwei
AlCl 3 /amide (acetamide, propionamide, butyramide) ionic liquids were used as the electrolytes to study the electrodeposition behavior of aluminum on a tungsten electrode. Cyclic voltammograms on the tungsten electrode indicate that Al(III) ions can be reduced to aluminum only within the molar ratio range of 1.1 to 1.5 and the reduction potentials of Al(III) ions strongly depend on the molar ratio of AlCl 3 /amide. Raman spectra results reveal that the electroactive specie of AlCl 3 /amide ionic liquids is Al 2 Cl 7
− . Aluminum coatings were prepared at −0.25 V (vs. Al/Al 3+ ) and at 313 K in AlCl 3 /amide ionic liquids with the molar ratio of 1.3. The SEM and cross-sectional SEM images show that all the obtained aluminum films are silver-colored, thick, and adherent. The EDS and XRD analysis confirm that the obtained deposits are pure aluminum. The present results can provide a new route for aluminum electrodeposition under ambient conditions.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Plants-Basel
·
2024
·Vol. 13
·期 4
·543
·
IF 4
Long Lu,Xinyu Chen,Qinyan Tan,Wenqian Li,Yanyan Sun,Zaoli Zhang,Yuanyuan Song,Rensen Zeng
Aluminum toxicity poses a significant constraint on crop production in acidic soils. While phytohormones are recognized for their pivotal role in mediating plant responses to aluminum stress, the specific involvement of gibberellin (GA) in regulating aluminum tolerance remains unexplored. In this study, we demonstrate that external GA exacerbates the inhibitory impact of aluminum stress on root growth of rice seedlings, concurrently promoting reactive oxygen species (ROS) accumulation. Furthermore, rice plants overexpressing the GA synthesis geneSD1exhibit enhanced sensitivity to aluminum stress. In contrast, theslr1gain-of-function mutant, characterized by impeded GA signaling, displays enhanced tolerance to aluminum stress, suggesting the negative regulatory role of GA in rice resistance to aluminum-induced toxicity. We also reveal that GA application suppresses the expression of crucial aluminum tolerance genes in rice, includingAl resistance transcription factor 1(ART1),Nramp aluminum transporter 1(OsNramp4), andSensitive to Aluminum 1(SAL1). Conversely, theslr1mutant exhibits up-regulated expression of these genes compared to the wild type. In summary, our results shed light on the inhibitory effect of GA in rice resistance to aluminum stress, contributing to a theoretical foundation for unraveling the intricate mechanisms of plant hormones in regulating aluminum tolerance.
研究领域:
植物学
·
遗传学
·
植物生理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
·
2024
·
IF 6.9
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 .
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
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
FUEL
·
2024
·
IF 6.7
Chunlong Jiang,Haobo Bi,Qizhao Lin,Zhanshi Ni
Aluminum is a widely used high-energy material. However, under environmental conditions, it is easy to form a layer of oxide cap on the surface of aluminum particles, which hinders the combustion of aluminum powder. In this paper, different oxides (MgO, SiO 2 , Fe 2 O 3 and CuO) were added to aluminum powder to study the influence of different additives on the combustion process of nano aluminum (nAl). It is found that four additives can improve the combustion rate of nAl in high temperature environment, especially Fe 2 O 3 and CuO. The molecular structure, element distribution and micro morphology of the combustion products were analyzed by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). In addition, combined with the thermogravimetric experiment, it is found that under the temperature programmed condition, the influence of four oxides on the combustion process of nAl was not obvious.
研究领域:
材料科学
·
燃烧化学
✓ 已验证
产品关联
DOI
高影响因子
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
·
2024
·
IF 4.7
Qiang WANG,Meng WANG,Zong-yu FENG,Yong-qi ZHANG,Xiao-wei HUANG,Xiang-xin XUE
For a highly efficient recycling of a wastewater containing a high concentration of MgCl 2 , Al(III) and P507 were scheduled to be removed in advance. In this study, the in-situ removal of Al(III) and P507 from a high concentration MgCl 2 solution at different pH values and Al/P molar ratios was investigated. The results showed that P507 formed organic complexes of Al x (OH) z + y -P507 at pH of 2.0−4.0. At pH of 4.0−5.0, Al(III) precipitated and transferred into Al(OH) 3 with a flocculent amorphous morphology. Active sites on the Al(OH) 3 surface enhanced the removal efficiency of P507. At pH of 6.0−6.5, Al(III) and Mg(II) formed layered crystalline Al(OH) 3 and MgAl 2 (OH) 8 with small pore channels and fewer active sites, resulting in a reduced removal efficiency of P507. When the Al/P molar ratio exceeded 13 and the pH was between 4.0 and 5.0, the removal rates of both Al(III) and P507 were higher than 98%, while the concentration loss of Mg(II) was only 0.2%−0.9%.
研究领域:
环境科学
·
化学工程
✓ 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）