JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
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2024
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IF 5.9
Chen Li,Chuncai Zhou,Wenwen Li,Wenrui Zhu,Jiaqian Shi,Lei Wu,Guijian Liu
Coal fly ash (CFA) is a promising alternative source for critical elements. Most of the critical elements in CFA are associated with the aluminosilicate glassy phase , which hinders their ability to solubilize during acid leaching. In this study, critical elements (Li, Be, Rb, Sr, Zr, Nb, Cs, Hf, Ta, Ga, Ge, Se, Cd, and Tl) were recovered from CFA of Pingwei power plant in China by alkali fusion-organic acid leaching. The results showed that the leaching rate of critical elements after alkali fusion was higher than that of direct organic acid leaching. The leaching rate of total critical elements was 72.56% under the optimal conditions. Among them, the highest leaching rate of Li, Be and Ga was more than 90%, and the highest leaching rate of Ge, Se, Rb, Sr, Zr, Nb, Cd, Cs and Hf was 70%-90%. Characterization analysis revealed that the amorphous aluminosilicate and silica phases in the raw CFA were destroyed by alkali fusion, resulting in nepheline and soluble aluminosilicate phases which were easily dissolved by citric acid . This study provides theoretical basis and technical support for the extraction of critical elements from CFA.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
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2024
·Vol. 31
·期 39
·52582-52595
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IF 0
Zhou Hao,Dang Yan,Chen Xinyu,Ivanets Andrei,Ratko Alexander A.,Kouznetsova Tatyana,Liu Yongqi,Yang Bo,Zhang Xulong,Sun Yiwei,He Xiaoyan,Ren Yanjie,Su Xintai
Due to industrialization, soil heavy metal pollution is a growing concern, with humic substances (HS) playing a pivotal role in soil passivation. To address the long duration of the compost humification problem, coal fly ash (CFA) in situ catalyzes the rapid pyrolysis of the cotton stalk (CS) to produce HS to address Cd passivation. Results indicate that the highest yield of humic acid (HA) (8.42%) and fulvic acid (FA) (1.36%) is obtained when the CS to CFA mass ratio is 1:0.5, at 275 ℃ for 120 min. Further study reveals that CFA catalysis CS humification, through the creation of alkaline pyrolysis conditions, Fe 2 O 3 can stimulate the protein and the decomposition of hemicellulose in CS, and then, through the Maillard and Sugar-amine condensation reaction synthesis HA and FA. Applying HS-CS&CFA in Cd-contaminated soil demonstrates a 26.69% reduction in exchangeable Cd within 30 days by chemical complexation. Excellent maize growth effects and environmental benefits of HS products are the prerequisites for subsequent engineering applications. Similar industrial solid wastes, such as steel slag and red mud, rich in Fe 2 O 3 , can be explored to identify their catalytic humification effect. It could provide a novel and effective way for industrial solid wastes to be recycled for biomass humification and widely applied in remediating Cd-contaminated agricultural soil.
研究领域:
环境科学
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土壤修复
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DOI
PubMed
RESOURCES CONSERVATION AND RECYCLING
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2023
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IF 13.2
Li Cui,Lijuan Feng,Hefeng Yuan,Huaigang Cheng,Fangqin Cheng
The recovery of critical metals from industrial waste is very important and challenging. This work proposed an efficient process for recovering aluminum, lithium, iron and gallium from coal fly ash leachate. Firstly, 98.1 %, 86.6 % and 99.8 % of iron, lithium and gallium are coextracted by tributyl phosphate (TBP), facilitating the subsequent use of the aluminum raffinate. The spectroscopic analysis verifies the formation of [Li(TBP) 2 ][FeCl 4 ] and [Li(TBP) 2 ][G a C l 4 ]. Afterwards, the effective separation of lithium, iron, gallium in TBP is achieved by stepwise stripping. Lithium can be almost completely stripped using 6 mol/L HCl with free iron and gallium of loss. An extremely high separation factor of iron and gallium (α Fe/Ga , 1175) can be achieved through reduction stripping by precisely controlling pH value and oxidation–reduction potential. Finally, about 99.5 % of gallium can be stripped with 0 ∼ 1 mol/L HCl. This work realizes the synergistic recovery of valuable metals from waste resources.
研究领域:
环境科学
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冶金工程
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DOI
高影响因子
FUEL
·
2023
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IF 7.4
Hongxia Fang,Chuncai Zhou,Shihai Xu,Jiaqian Shi,Yunhu Hu,Guijian Liu,Lei Wu
Metal-organic frameworks (MOFs) are considered one of the promising adsorbents for CH 4 /N 2 separation. However, MOFs commercialization is a big challenge since their synthetic materials are expensive and not environmentally friendly. Herein, the dealumination solution obtained from coal fly ash (CFA) using sulfuric acid as an extracting agent through direct leaching and roasting technologies was applied as metal feedstock to prepare CFAx-FumMOF-y and compared to aluminum fumarate MOF (Al-FumMOF) in morphology, surface area, micropore volume, and CH 4 /N 2 selective separation. The results indicated that CFAx-FumMOF-y exhibited closely similar surface area (1164.94–1073.08 m 2 /g) and micropore volume (0.40–0.36 cm 3 /g) to Al-FumMOF (1287.55 m 2 /g, 0.42 cm 3 /g), even there were no detectable differences in CH 4 uptakes (CFAx-FumMOF-y, 21.93–20.69 cm 3 /g; Al-FumMOF, 22.13 cm 3 /g) at 298 K and 1.0 bar, suggesting that the impurity metal species in dealumination solution hardly affect textural properties and gas uptakes. Moreover, the isosteric heat of adsorption (Q st ) and IAST CH 4 /N 2 selectivity of CFAs-FumMOF-1 (19.25–17.84 kJ/mol) and CFAb-FumMOF-1 (18.83–18.64 kJ/mol) were slightly superior to Al-FumMOF (17.83.64–16.86 kJ/mol, 4.87), suggesting that CFAx-FumMOF-1 played an identical role as Al-FumMOF in gases separation. The cyclic regeneration experiments and binary breakthrough tests further confirmed that CFAx-FumMOF-y was feasible for practical application. This study provides a new perspective for reducing the production cost of MOFs as well as realizing high-value utilization of CFA.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
PHILOSOPHICAL MAGAZINE
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2022
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IF 1.948
Ailian Zhu,Yupeng Xie,Keyou Shi,Min Chen,Jiawei Li,Yimin Zhou,Gaiyuan Chen,Yong Liu
Coal fly ash (hereinafter CFA) was employed to rapidly immobilise Nd-contaminated soil with the addition of TiO2 via microwave sintering technology. The effect of TiO2 doping on the phase composition, microstructure, elemental distribution, density, and chemical durability of the solidified samples was systemically investigated. The results indicated that the Nd element can be incorporated in the matrix with oxyapatite and pyrochlore as TiO2 content increased at 1200°C. Moreover, the sintered sample with the high bulk density and low open porosity was fabricated at a TiO2-doping amount of 7 wt.%. Meanwhile, the as-prepared samples doping with TiO2 exhibited excellent chemical durability. Especially, the sintered sample doping with 3 wt.% TiO2 had the lowest leaching rate (7.97×10−6 g·m−2·d−1 at 28 d). Our investigation reflects that CFA is suitable for Nd-contaminated soil immobilisation via microwave sintering technology and the introduction of TiO2 is conducive to the improvement of densification and chemical durability.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2022
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IF 14.224
Xiao-lu Fan,Jin-lan Xia,Duo-rui Zhang,Zhen-yuan Nie,Yun-peng Liu,Li-juan Zhang,Da-yi Zhang
A novel sinter method using ZnO as the activator instead of the conventional Na 2 CO 3 /CaCO 3 , (NH 4 ) 2 SO 4 , and K 2 S 2 O 7 was developed to achieve efficient sequential extraction of rare earth elements (REEs), alumina (Al), and silica (Si) from coal fly ash (CFA). Up to 93.3% Si, 87.1% REEs (70.7% Ce, 82.5% La, 83.2% Gd, 87.1% Nd, 62.3% Dy, and 81.7% Y), and 92.9% Al were extracted from CFA, respectively. Moreover, 93.1% of the ZnO activator was efficiently recycled, and the yield of red mud was only 14.9%. X-ray diffraction (XRD) and X-ray absorption near edge structure (XANES) results showed that the speciation transformation of Al/Si during CFA/ZnO roasting was as follows: mullite , quartz, amorphous Al 2 O 3 , and SiO 2 → Zn 0.75 Al 1.5 Si 1.5 O 6 , kyanite and willemite → gahnite and quartz/cristobalite solid solutions . The change in the REEs occurrence mode hinted at the migration of most REEs in aluminosilicates forms with Si during roasting, and disassociation with Si into the acid-soluble form after alkali leaching. These results indicate that the coupling of Al-Si-REE in CF was broken by this ZnO sinter method, promoting the sequential and efficient extraction of REEs, Al, and Si from CFA. This study provides a green and efficient strategy for element recovery from CFA, substantially reducing residues and favoring REEs concentration.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
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2025
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IF 8.4
Lang Xing,Guanghui Li,Jun Luo,Hao Jiang
Large-scale comprehensive utilization of coal fly ash (CFA) has become an inevitable issue. In this study, one-step mixed alkali (KOH + CaO) hydrothermal extraction of alumina and synergistic preparation of soil amendment from CFA was developed. The Al 2 O 3 and SiO 2 in CFA were dissolved rapidly under the action of KOH, and the dissolved silicate was transformed into tobermorite under the action of CaO. This approach realized efficient separation of aluminum and silicon with simultaneous regeneration of KOH. The optimum leaching ratio of Al 2 O 3 was 56.44 %, while the leaching ratio of SiO 2 was 3.38 %. The dealuminated CFA (DACFA) was simultaneously transformed into porous aggregates intertwined with tobermorite fibers, which are rich in Si, Ca and K 2 O nutrients due to the excellent cation exchange of tobermorite or formation of tobermorite and leucite minerals. The effective Si, Ca, and K 2 O in F90 were 16.19 %, 20.45 % and 5.31 %, respectively, which met the primary standard of fertilizer. The pot experiment showed that DACFA effectively improved soil quality and immobilized soil heavy metals, thereby accelerating the growth of pakchoi. Through this technology, the high-value transformation from CFA to alumina and soil amendments is expected to facilitate large-scale utilization of CFA and enhance agricultural productivity.
研究领域:
环境科学
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材料科学
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农业科学
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产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
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2021
·Vol. 22
·期 12
·6540
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IF 5.924
Xu Zhang,Tao Du,He Jia
In this study, four different coal fly ashes (CFAs) were used as raw materials of silica and alumina for the preparation of the alumina-containing Mobil Composition of Matter No. 41 (Al-MCM-41) and the exploration of an activation strategy that is efficient and universal for various CFAs. Alkaline hydrothermal and alkaline fusion activations proceeded at different temperatures to determine the best treatment parameters. We controlled the pore structure and surface hydroxyl density of the CFA-derived Al-MCM-41 by changing the crystallization temperature and aging time. The products were characterized by small-angle X-ray diffraction, nitrogen isotherms, Fourier-transform infrared spectroscopy,29Si silica magic-angle spinning nuclear magnetic resonance, and transmission electron microscopy, and they were then grafted with thiol groups to remove Pb(II) from aqueous solutions. This paper innovatively evaluates the CFA activation strategies using energy consumption analysis and determines the optimal activation methodology and parameters. This paper also unveils the effect of the crystallization condition of Al-MCM-41 on its subsequent Pb(II) removal capacity. The results show that the appropriate selection of crystallization parameters can considerably increase the removal capacity over Pb(II), providing a new path to tackle the ever-increasing concern of aquic heavy-metal pollution.Keywords:coal fly ash;CFA activation;Al-MCM-41;crystallization parameters;Pb(II) removal capacity
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
WASTE MANAGEMENT
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2024
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IF 7.1
Huikang Song,Yaji Huang,Junfeng Pang,Zhiyuan Li,Zhicheng Zhu,Haoqiang Cheng,Jiawei Gao,Wu Zuo,Haiyun Zhou
Medical waste incineration ash (MWIA) has significant concentrations of heavy metals, dioxins, and chlorine that, if handled incorrectly, might cause permanent damage to the environment and humans. The low content of calcium (Ca), silicon (Si), and aluminum (Al) is a brand-new challenge for the melting technique of MWIA. This work added coal fly ash (CFA) to explore the effect of melting on the detoxication treatment of MWIA. It was found that the produced vitrification product has a high vitreous content (98.61%) and a low potential ecological risk, with an initial ash solidification rate of 67.38%. By quantitatively assessing the morphological distribution features of heavy metals in ashes before melting and molten products, the stabilization and solidification rules of heavy metals during the melting process were investigated. This work ascertained the feasibility of co-vitrification of MWIA and CFA. In addition, the high-temperature melting and vitrification accelerated the detoxification of MWIA and the solidification of heavy metals.
研究领域:
环境科学
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医学废物处理
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
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2025
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IF 4.7
Ying Wang,Tengfei He,Jingguo Cao,Ke Li,Chengqian Wang,Qun Liu,Yu Zhang
This study demonstrates a sustainable strategy for synthesizing MIL-53(Al) and ZSM-5 zeolite through dual-waste synergy using coal fly ash (CFA) and waste polyethylene terephthalate (PET). A sequential alkaline fusion-acid leaching protocol selectively fractionated CFA into aluminum-rich solutions and silica residues, while alkaline hydrolysis of PET liberated terephthalic acid (PTA) as organic ligands. The Al 3+ -PTA coordination under solvothermal conditions produced MIL-53(Al)(CFA-PET) exhibiting well-defined 1D rhombic channels with a high BET surface area (1303 m 2 ·g −1 ), whereas hydrothermal crystallization of silica residues yielded ZSM-5(CFA), which formed spherical aggregates composed of 100 nm nanosheets with 89.9 % yield and a surface area of 311 m 2 ·g −1 . Structural advantages were evidenced by exceptional adsorption performance: MIL-53(Al)(CFA-PET) achieved 96.24 % methylene blue removal at pH 7 (250 mg·L −1 ), outperforming rhodamine B (30.8 %) and methyl orange (66.4 %), as well as reagent-synthesized MIL-53(Al) Che (91.99 %). Both materials demonstrated exceptional CO 2 capture capacities (4.23 mmol·g −1 for MIL-53(Al)(CFA-PET) vs. 2.37 mmol·g −1 for ZSM-5(CFA) at 273 K/1 bar), attributable to MIL-53′s flexible framework enabling dynamic pore adjustment and ZSM-5′s rigid microporous channels favoring molecular sieving. This work establishes a closed-loop strategy for converting industrial and plastic wastes into functionally differentiated porous materials through element-targeted process design.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Water Process Engineering
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2024
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IF 6.3
Hongxia Fang,Chuncai Zhou,Shihai Xu,Jiaqian Shi,Yunhu Hu,Guijian Liu
Developing a low-cost and high-performance adsorbent to eliminate cadmium (Cd) pollution in farmland irrigation water is highly desired. Herein, a hierarchically structured calcium silicate hydrate (CSH) material was prepared from the alumina-extracted residue (AR) of coal fly ash to remove low concentration of cadmium [Cd(II)] (0.1 mg/L) from simulated farmland irrigation water. The results indicated that CSH with different Si/Ca ratios exhibited excellent adsorption performance with a removal efficiency of over 90 %. Among them, CSH with Si/Ca ratios of 0.83 (CSH-0.83) had the highest removal rate, reaching 99.38 %. Under the optimum operation conditions of adsorbent dosage of 0.04 g/L, pH value of 4.0, contact time of 120 min, and initial concentration of 0.06 mg/L, the maximum adsorption rate of Cd(II) was 99.42 %. The adsorption isotherms and kinetics results showed that the adsorption and desorption process of Cd(II) by CSH-0.83 could be well fitted by pseudo-second-order (R 2 = 99 %) and its adsorption isotherms accorded with the Langmuir model (R 2 = 98 %). The adsorption mechanism was mainly chemosorption. The released calcium (Ca 2+ ) and hydroxyl (OH − ) from the CSH-0.83 reacted with Cd(II) via complexation, or Cd(II) underwent ion exchange with Ca 2+ adsorbed on the surface or edge of the particle. Furthermore, CSH-0.83 exhibited good stability and regeneration capacity, and its adsorption efficiency remained at 86.45 % in the sixth cycle. This study provides new ideas for high-value utilization of similar solid waste of aluminosilicates .
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
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IF 5.1
Shize Chen,Liming Luo,Hongjuan Sun,Tongjiang Peng,Jie Lei,Jin Yang,Zijun Xian
Industrial solid waste poses serious risks to the human living environment and health owing to its diversity and complexity. In this work, asbestos tailings and coal fly ash were used as raw materials, and the trivalent actinide nuclide was simulated using Nd 2 O 3 . The silicate glass-ceramics nuclide solidified body was successfully prepared through melting, water quenching, and sintering methods. The properties of the solidified body and the solidification mechanism of the nuclide were studied via X-ray diffraction, Scanning electron microscope-energy dispersive spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, and Atomic pair distribution function analysis. The results showed that the solidified body prepared via the molten water quenching–sintering method exhibited a unique microcrystalline structure, with properties that were significantly superior to those of traditional glass solidified bodies. Increasing the amount of Nd 2 O 3 further enhanced the stability of the solidified body. However, when the amount of Nd 2 O 3 exceeded 22 wt%, both the compressive strength and bulk density of the sample decreased. Therefore, the optimal package capacity of the solidified body for the nuclide Nd was 22 wt%. The leaching experiment demonstrated that the normalised leaching rate of Nd stabilised after 14 d and reached the order of 10 −5 g m −2 d −1 after 42 d, which indicated that the solidified body had excellent curing ability for nuclides. Analysis of the glass network structure revealed that Nd elements formed short-range ordered structures with Al, Si, Mg, O, and other elements through non-bridging oxygen bonds, thus becoming fixed in the amorphous phase of the solidified body. When the amount of Nd 2 O 3 exceeded 20 wt%, some short-range ordered structures containing Nd transitioned to form long-range ordered structures, which were stabilised in the crystal phase through lattice solidification. Overall, this study provides an experimental and theoretical basis for the solidification of highly radioactive nuclides using industrial solid waste.
研究领域:
材料科学
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环境科学
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核废料处理
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）