SEPARATION AND PURIFICATION TECHNOLOGY
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2025
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IF 9
Xinyu Yang,Bing Hou,Zongsheng Hu,Hao Jiang,Nan Li,Jingwen Pan,Lei Wang
Fluoride (F − ) pollution in surface water seriously endangers ecological safety. Cerium-based adsorbents have original advantages in adsorbing F − such as abundant oxygen vacancies and variable valence states. However, high cost and separation difficulty limit their application in fluoridated surface water treatment. This work synthesized bimetallic oxide adsorbents (FeCe@C) to enhance the efficacy of cerium-based adsorbents for F − removal and systematically examined how Fe(II) doping influenced fluoride removal efficiency. Results indicated that FeCe@C adsorbed F − better than the pure Ce-based adsorbent (Ce@C), with q max = 243.31 mg/g at 25℃, and reached adsorption equilibrium in merely five minutes, with significantly better adsorption performance than fluoride adsorbents reported in previous literature. F − adsorption process aligned with the Temkin (R 2 > 0.963), pseudo-second-order kinetic (R 2 > 0.999) and Elovich model (R 2 > 0.993), suggesting that the F − adsorption mechanism was governed by chemisorption-dominated heterogeneous surface reactions. Further results proved that the doping of iron exhibited a significant effect on the generation of Ce(III) active sites and oxygen vacancies in FeCe@C, which showed a positive correlation (R 2 = 0.87 and 0.98). And unlike other metal doping mechanisms, the doped Fe species promoted the formation of Ce(III) through redox reactions during the adsorption process, achieving the reverse conversion of Ce(IV) to Ce(Ⅲ), rather than directly participating in adsorption. Density functional theory (DFT) calculations demonstrated that iron doping effectively enhanced electron transfer and the interaction between F − and the adsorbent, resulting in a higher F − adsorption capacity. This study provides fundamental theory for enhanced fluoride removal and offers new ideas for elevating the efficacy of cerium-based adsorbents.
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
SEPARATION AND PURIFICATION TECHNOLOGY
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2025
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IF 9
Bing Hou,Ling Wang,Xinyu Yang,Yuyou Li,Zhuohang Wu,Jingwen Pan,Lei Wang
Cerium-based adsorbent with the merits of variable valence and ample oxygen vacancies was applied for the removal of highly toxic hexavalent chromium (Cr(VI)). However, its cost controllability and recycling stability in practical applications remain to be further explored. Herein, a varieties of bimetallic cerium-based biochar adsorbents (CeFe@BC) were prepared by doping iron (Fe) and loading onto straw-based biochar, and the effects of the introduced Fe and biochar on adsorption performance of cerium-based adsorbent for Cr(VI) were studied. In comparison to pure cerium-based adsorbent (Ce@C), CeFe@BC had a stronger Cr(VI) adsorbability with the maximum adsorption capacity of 57.05 mg/g (25°C). Meanwhile, CeFe@BC had good regeneration stability and environmental friendliness. The adsorption capacity only decreased by 16.11 % after 7 adsorption–desorption cycles, with almost no metal leaching in different pH. Results showed that Fe doping and loading onto straw-based biochar could effectively promote Ce(III) and oxygen vacancy content in Ce@C. Electrochemical and density function theoretical calculations proved that Fe doping and loading onto straw-based biochar could promote the reduction of Ce@C impedance and the increase of current density. In conclusion, Fe doping and loading onto straw-based biochar effectively regulated the intrinsic properties of cerium adsorbent and further accelerated the electron transfer in adsorption. This study shows that bimetallic cerium-based adsorbent is a promising, efficient and stable environmental friendly adsorbent for Cr(VI) removal from wastewater.
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
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Tao Zhang,Sujie Shan,Dongqing Liu,Yu Han,Kai Sun,Wei Wang
Under the double pressure of eutrophication and phosphorus deficiency, there is an urgent need to remove excess phosphate from wastewater efficiently. Preparing cerium-based materials with excellent application potential inevitably leads to Ce(III) oxidation to Ce(IV), which reduces the phosphate adsorption effect and restricts its development. To solve this problem, we introduced a protective agent and successfully synthesised cerium-modified activated carbon sorbent containing 100 % Ce(III) during the synthesis process. Compared with CeAC without a protecting agent, CeAC-A contained more Ce(III) (100 %) and exchange groups (–OH accounted for 82.76 %), achieving an adsorption capacity of up to 448.57 mg-P/g Ce, improving of 4.3 times. At the same time, the size of the cerium active component was reduced from the micron level to the nanometer level, and the mass transfer rate was significantly improved. In addition, with the enormous specific surface area and well-developed pore structure of activated carbon, it showed high dispersibility, with P/Ce molar ratio as high as 2.03, which is 1.1–4.8 times higher than other cerium-based adsorbents. Phosphate was removed primarily through electrostatic attraction and ligand exchange. In treating municipal wastewater with complex water quality, CeAC-A showed strong selectivity, a wide range of adaptability and easy repeat regeneration, making it a promising adsorbent for phosphate uptake from wastewater.
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
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Xinyu Yang,Bing Hou,Mingjing Shi,Muhammad Akram,Xinxin Li,Lei Wang,Jingwen Pan
Excessive fluoride (F − ) in water environment is a widespread concern, and economical and efficient adsorption is widely used defluorination technology. In this study, a series of cerium-based adsorbents (Ce@C) with different structural properties were synthetized by adjusting the calcination conditions to explore their effect on the F − adsorption capacity of Ce@C and intrinsic mechanism. Results indicated that the best performing Ce@C had the maximum adsorption capacity (340.71 mg/g) and a wide pH working range (2–12). The adsorption process of F − conformed to the pseudo-second-order model and the Temkin model, proving that F − adsorption onto Ce@C was mainly dominated by chemisorption. Different calcination conditions altered the content of Ce(III) and oxygen vacancies in Ce@C, and their contents exhibited a significant effect on the F − adsorption performance of Ce@C, which showed a strong positive correlation (R 2 = 0.982 and 0.933). Density functional theory (DFT) calculations further proved that the presence of Ce(III) and oxygen vacancies could provide richer coordination numbers to promote the complexation of F − and Ce@C. This work re-reveals the F − adsorption behavior and intrinsic mechanism onto cerium-based adsorbents, and also provides a theoretical basis for the subsequent design of cerium-based adsorbent materials for defluorination.
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
CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Tao Zhang,Junle Li,Dongqing Liu,Yuling Ma,Yu Han,Sujie Shan,Kai Sun,Elena V. Zelinskaya,Aijie Wang,Hongliang Sun,Wei Wang
Under the dual challenges of water eutrophication and phosphorus deficiency, efficient adsorbents are urgently needed to remove and recover excess phosphate. However, the highly regarded cerium-based adsorbent has become the main difficulty limiting its large-scale application due to its high energy consumption and uncontrollable valence state in the synthesis process. To address this issue, we synthesized a composite cross-linked framework adsorbent (CCFA) using a simple coprecipitation method for application as a novel phosphate trap. Due to the realization of 100 % Ce(III) acquisition, CCFA exhibited a high adsorption capacity of up to 289.18 mg-P/g·Ce, 1.5 to 2 times higher than existing cerium-based adsorbents. At the same time, the introduction of sepiolite not only improved the utilization efficiency of the active sites, resulting in a high P/Ce molar ratio of 1.31, but also enhanced the resistance to pH interference, with the adsorption capacity only decreasing by 16.5 % in the presence of strong alkali (pH = 11). In addition, CCFA exhibited a wide range of adaptability, excellent phosphate recovery potential, and the prospect of large-scale application, making it a promising adsorbent for wastewater phosphate.
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
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2024
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IF 9.4
Bing Hou,Xinyu Yang,Ling Wang,Tao Shi,Muhammad Akram,Lei Wang,Jun Wan,Baoyu Gao,Jingwen Pan
Cerium-based adsorbents possessed unique advantages of valence variability and abundant oxygen vacancies in hexavalent chromium (Cr(VI)) adsorption, but high cost and unstable properties restricted their application in Cr(VI) contained wastewater treatment. Herein, a series of bimetallic adsorbents with different cerium/iron ratios (CeFe@C) were prepared by adding inexpensive Fe into Ce-based adsorbents (Ce@C), and the effect of Fe doping on adsorption properties of Ce@C for Cr(VI) was investigated thoroughly. Compared with pristine Ce@C, CeFe@C exhibited excellent removal performance for Cr(VI), and the improved maximum adsorption capacity reached 75.11 mg/g at 25℃. Benefiting from Fe doping, CeFe@C had good regeneration property, with only 25 % decrease after five adsorption–desorption cycles. Contents of trivalent cerium (Ce(III)) and oxygen vacancies (O v ) in bimetallic adsorbents were positively correlated with divalent iron (Fe(II)) doping, indicating that the formation of Ce(III) and surface defects on Ce@C could be effectively regulated by Fe doping. Density functional theory (DFT) calculation results further proved that the doped Fe enhanced the electron transfer effectively and lowered the energy barriers of Cr(VI) adsorption onto Ce@C surface, strengthening the reduction and complexation to Cr(VI). This study provides new insights for improving the Cr(VI) removal performance by modified Ce-based adsorbents, and further promotes the utilization potentiality of low-cost and low-toxicity Ce-based adsorbents in Cr(VI)-containing wastewater treatment.
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
Journal of Environmental Chemical Engineering
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2025
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IF 7.2
Daoqing Liu,Biao Wei,Chen Zhang,Qianwei Li
The application of various surface-modified and nano-sized metal-based adsorbents has demonstrated impressive efficiency in phosphate recovery and reuse. However, current research predominantly focuses on the material properties and phosphate adsorption efficiency, often overlooking methods to optimize the phosphate adsorption process. In this research, we introduce a strategy to enhance phosphate removal by modulating the valence state of cerium hydroxide nanoparticles (CHN) through a redox process. Using a simple reduction method with vitamin C, the Ce(III) content and surface hydroxyl groups increased significantly in CHN, resulting in a substantial improvement in phosphate adsorption. The maximum adsorption capacity of vitamin C-treated cerium hydroxide nanoparticles (VC-CHN) reached 113.4 mg P g⁻¹ , 2.2 times higher than untreated CHN. Furthermore, adding a small amount of persulfate (PDS) to the alkaline desorption solution significantly optimized the phosphate desorption process, effectively mitigating the inhibition caused by natural organic matter (NOM). This redox modulation strategy allowed the CHN adsorbent to maintain excellent reusability in natural water containing complex chemical species. Therefore, modulating redox processes offers a novel and effective approach for removing and recovering phosphate using metal oxide adsorbents.
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
CHEMOSPHERE
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2020
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IF 5.778
Jiaojie He,Yuhong Xu,Zhaokun Xiong,Bo Lai,Yan Sun,Yue Yang,Liwei Yang
Trivalent cerium (Ce(Ⅲ)) was demonstrated to have great potential for phosphate (P) removal. Besides the valence states, the relationship of nano-structure and adsorption capacity needs further study to explore more efficient adsorbents. Herein, a series of Ce(Ⅲ)-terephthalate (BDC) metal-organic framework (MOF) with linker deficiencies are fabricated to achieve excellent P capture. The defective density can be increased by decreasing the reaction time and the ratio of organic linkers/metal. TGA reveals Ce-BDC-48 synthesized with BDC:Ce ratio of 1:1 for 48 h possessed 2.5 missing linkers per inorganic node. And the P uptake of Ce-BDC-48 was 35% higher than that of Ce-BDC-72 without defects. The maximum adsorption capacity of Ce-BDC-48 was 278.8 mg/g for P and 128.0 mg/g for fluoride (F), respectively. The adsorption mechanism illustrates that both P and F mainly focus on the Ce(Ⅲ) active sites to achieve ligand exchange . The competing adsorption of P and F at the lower concentration of F (50 mg/L) indicates that the interference of F for P removal is insignificant on account of the selective preferential order of P. However, with the increment of F concentration (100 mg/L), amount of F with small sizes gathering around the adsorbent surface enlarge the steric hindrance to hinder the access of P, leading to the sharp decline of P uptake. This study not only provides promising candidate by the design of structural defects for the P removal in practical application but also give a deep analysis on the adsorption mechanism of P with competing F surrounded.
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
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