SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Wenze Zhang,Yukun Duan,Xiaopeng Chi,Wen Tan,Wei Weng,Shuiping Zhong
In the zinc production industry using Mn-rich zinc ore, substantial quantities of anodic slime are generated during electrolytic zinc production, containing ∼ 40 % Mn and ∼ 3 % Pb. While a valuable secondary resource, this material poses environmental risks as solid waste. Conventional reductive leaching methods rely on costly reductants and generate high carbon emissions. This study introduces a process utilizing flue gas from zinc plants as a reductant, achieving 92 % Mn leaching efficiency while simultaneously extracting 25 % Sr and fixing 92 % SO 2 as sulfate in solution. Kinetic analysis shows a mixed control model with an activation energy of 13.83 kJ/mol, with reaction rates further enhanced by optimizing gas inlet design. The MnSO 4 -rich leachate is processed into battery-grade MnSO 4 powder, and Sr is recovered as SrCO 3 , suitable for use as an additive in electrolytic zinc processes. Additionally, NaOH consumption for flue gas desulfurization decreases significantly from 2.14 kg to 0.17 kg per Nm 3 . Economic evaluation indicates reagent costs represent only 2 % of the total value of MnSO 4 and SrCO 3 products, offering a sustainable pathway for anodic slime utilization and SO 2 mitigation in zinc smelting.
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
CHEMOSPHERE
·
2022
·
IF 8.943
Yongkui Li,Xianjin Qi,Guohua Li,Xiaoxu Duan,Nina Yang
High-arsenic wastewater has long been considered a major threat to ecological balance and human health because of its strong toxicity and high mobility. Herein, an environmentally friendly process was proposed for As removal and fixation in the form of As-stabilized mineral, using Lead–Zinc smelting (LZS) slag as the in situ Fe donor, neutralizer, and crystal seed. The slag was dissolved in the wastewater and released Fe and Ca ions, while simultaneously increasing the pH value of the solution to help scorodite synthesis. The dissolved Ca 2+ ion preferentially reacted with SO 4 2− ion in the form of CaSO 4 ·2H 2 O precipitate as in situ “seeds” for As precipitation. The dissolved Fe(II) and As(III) ions were oxidized to Fe(III) and As(V) ions by H 2 O 2 , and later reacted with each other to generated amorphous ferric arsenate on the surface of CaSO 4 ·2H 2 O, and then evolved into scorodite crystals with high stability. With a Fe/As molar ratio of 2, a reaction temperature of 90 °C, and a reaction time of 12 h, 98.42% of As was effectively precipitated from the wastewater with an initial As concentration of 7530.00 mg/L. Moreover, the leached As concentration of the As-bearing precipitate in the TCLP test was 3.46 mg/L. The concentration of the residual As and heavy metals ions in the final filtrate was lower than local wastewater discharge standards, successfully realizing the treatment of smelting wastewater. In summary, a prospective process successfully shows a great potential for co-treatment of LZS wastewater and slag, which could advance the large-scale disposal of LZS plants.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
·
2021
·
IF 8.071
Qiushi Zhang,Xing Cao,Shichang Sun,Weichen Yang,Lin Fang,Rui Ma,Chenghua Lin,Haowen Li
Lead-zinc slag (LZS) is a solid waste product that is rich in silicon and aluminum and has enormous resource potential for functional environmental functional geopolymer materials. Unfortunately, the solidification mechanism of heavy metals in geopolymers is still unclear, which is detrimental to the heavy metal solidification of LZS. In this study, we comprehensively studied and demonstrated the solidification mechanisms of Pb and Zn in geopolymers, based on the preparation of high-performance LZS-based geopolymers (compressive strength up to 89.3 MPa, and Pb and Zn solidification efficiency up to 93.1% and 90.0%, respectively). Thereafter, the solidification mechanism differences between Pb and Zn were explained by electronegativity and ion potential. Due to the ionic potential order of Zn 2+ > Pb 2+ > Na + , both Zn 2+ and Pb 2+ could exchange with Na + in the geopolymer. In addition, due to the electronegativity order of Pb > Si > Zn, Pb could attack the [SiO 4 ] structure and form covalent bonds in the Pb–O structure, while Zn did not (shown by Raman spectroscopy). As a result, Pb simultaneously solidified in the geopolymer through covalent bonding and ion exchange, while Zn was solidified mainly by ion exchange. Thus, this work provides new perspectives and ideas for the solidification mechanisms of heavy metals in geopolymers.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2023
·Vol. 34
·期 11
·1-16
·
IF 2.8
Shi Jiahao,Duan Xiaoxu,Qi Xianjin,Li Guohua,Yan Guizhi,Wang Heng
Acidic arsenic-containing wastewater from copper smelting poses a potential threat to human and environmental safety due to its high toxicity, acidity, high volumes, and difficulty to be processed and utilized. This study proposed a technique to leach environmentally stable scorodite from wastewater using natural zinc slag as a solid iron source. The leaching behavior of scorodite was investigated through a combination of room-temperature adsorption and high-temperature reactions, after which the underlying mechanisms of this reaction were explored through adsorption kinetics and thermodynamics. Our findings indicated that the optimal reaction conditions of zinc slag with wastewater were the following: Fe/As ratio = 2.5, 80 °C, 10 h. The initial arsenic concentration in the wastewater was reduced from 13,040 mg/L to 140.5 mg/L, with 98.9% of the arsenic being removed. The toxicity characteristic leaching procedure (TCLP) results for the precipitates showed that the leaching concentration of arsenic was only 2 mg/L. For Fe 2 SiO 4 in zinc slag, FeS dissolves to release iron ions, generating FeAsO 4 ·2H 2 O, FeAsO 4 , and secondary minerals. Ca 2 Al 2 SiO 7 generates gypsum to provide surface active sites for the growth of scorodite. This study proposes the industrial application of zinc slag for arsenic removal from copper smelting wastewater, providing a strong methodological basis to promote the development of non-ferrous metallurgical enterprises in a green and efficient manner.
研究领域:
环境科学
·
冶金工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Hongrui Xiang,Feiping Zhao,Tao Wu,Xiaowei Zhang,Fei Chai,Qingwei Wang,Eveliina Repo,Xiaobo Min,Zhang Lin
Understanding the structure–activity relationship between the adsorption performance and accessible adsorption sites plays a vital role in developing efficient adsorbents for Ge(IV) recovery. Herein, three chitosan-based adsorbents were designed by grafting chitosan with p -hydroxybenzoic acid (HBA-CS), 3,4-dihydroxybenzoic acid (DBA-CS), and 3,4,5-trihydroxybenzoic acid (TBA-CS), and the phenolic hydroxyl amounts induced steric effect on Ge(IV) recovery was investigated. The results show that phenolic acids were successfully grafted onto the chitosan surface by an amidation reaction. The adsorption behavior of DBA-CS and TBA-CS conforms to the pseudo-second-order kinetic and Langmuir isotherm models, indicating that it is a single layer adsorption and chemisorption is the main adsorption process . The Ge(IV) recovery performance is correlated with the arrangement of the active adsorption sites and follows the order of TBA-CS > DBA-CS > HBA-CS. The steric effect of TBA-CS is more ideal than that of DBA-CS due to more phenolic hydroxyl groups, which endows it better affinity toward Ge(IV). Additionally, TBA-CS exhibits superior selectivity in the presence of competitive cations and interfering anions, and the adsorption efficiency was not significantly decreased after four regeneration cycles by the acid elution. The chelation adsorption sites for Ge(IV) provided by the o -phenolic hydroxyl groups are the dominant contribution, and the hydrogen bond and ideal steric effect further enhance the adsorption performance of TBA-CS. The structure regulation designed by steric hindrance optimization strategy to achieve high affinity is an attractive approach, which could be extended in the recovery of precious metal ions.
研究领域:
环境科学
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材料科学
·
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）