JOURNAL OF MOLECULAR LIQUIDS
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2022
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IF 6.633
Yaqin Song,Ting Jiang,Jiayu Wu,Jianqiu Chen,Qiong Du
Dissolved silicate (Si), which is omnipresent in natural water and wastewater, is a key factor mediating the separation and transformation of contaminants by forming complexes on the surface of zero-valent iron (ZVI) and iron oxides. In this study, we prepared an nZVI@D201 nanocomposite and studied the redistribution of sulfamethoxazole (SMX) on nZVI@D201 in the pre-equilibration and Si-SMX simultaneous addition systems with 0.1 mM and 1.0 mM Si at an initial pH of 3.0–11.0. The results revealed that both Si pre-equilibration and Si-SMX simultaneous addition exhibited excellent SMX removal efficiency. Si pre-equilibration altered the adsorbed SMX to degradative SMX at an initial pH of 5.0–9.0. Moreover, the simultaneous Si addition at increasing concentrations decreased the degradative SMX. X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy were used to characterize nZVI@D201 after pre-equilibration and simultaneous addition of Si and SMX at an initial pH of 5.0. The results showed that Si pre-equilibration inhibited the transformation of ZVI to magnetite and decreased the crystallinity of the minerals. In addition, the simultaneous addition of Si and SMX impeded the transformation of nZVI to magnetite, whereas the formation of Fe-O-Si complexes hindered the crystallinity. Moreover, scavenger experiments and electron spin resonance tests proved that addition of Si didn’t change the reactive species formation and ·OH was the mainly species for SMX degradation. Based on the detected intermediates via ultra-high performance liquid chromatography-mass spectra, the possible degradation pathways of SMX were proposed.
研究领域:
环境科学
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化学
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产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
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2025
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IF 5.1
Yongshuang Hu,Guqing Xiao,Yi Sun,Qiudong Meng
Glyphosate, the most widespread organophosphorus herbicide, enters lakes, rivers and groundwater through rainwater and surface runoff. It is very important to remove glyphosate from neutral water bodies. A new strategy for the development of glyphosate adsorbent was implemented through in situ nanoconfinement of hydrated ferric oxide (Fe 2 O 3 ·nH 2 O) in an anion exchange resin D201 (D201/Fe 2 O 3 ·nH 2 O). Fe 2 O 3 ·nH 2 O was confined within the 12–140 nm pores of D201/Fe 2 O 3 ·nH 2 O, exhibiting uniform distribution, nanoscale and amorphous state. Benefiting from the cross-linked polystyrene network, D201/Fe 2 O 3 ·nH 2 O featured excellent chemical stability in weakly acidic (pH > 3), alkaline and salt solutions. Compared with its host D201, D201/Fe 2 O 3 ·nH 2 O exhibited larger rate constant k 1 , larger glyphosate capacity and superior selectivity at pH = 7.0 ± 0.05. Corresponding its bifunctional groups of -N + (CH 3 ) 3 and Fe 2 O 3 ·nH 2 O, D201/Fe 2 O 3 ·nH 2 O could adsorb glyphosate through the two mechanisms of the ligand exchange between glyphosate anion and hydroxyl group, as well as the anion exchange between Cl − and glyphosate anion. D201/Fe 2 O 3 ·nH 2 O showed the commendable reusability and maintained constant glyphosate adsorption capacities at 161.5–164.5 mg/g in five consecutive adsorption-regeneration cycles. At the injection glyphosate concentration of 1.1 mg/mL, the effective processing volumes of D201/Fe 2 O 3 ·nH 2 O were 3.81 and 3.21 times that of D201 at two breakthrough points.
研究领域:
环境科学
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材料科学
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化学工程
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水资源保护
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污染物处理
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DOI
高影响因子
Processes
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2021
·Vol. 9
·期 12
·2195
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IF 2.847
Yi Qian,Haoyan Fu,Long Li,Wenyuan Su,Jiayin Li,Yihao Zhang
Due to the widespread use of antibiotics in medical treatment, animal husbandry and aquaculture, a large number of antibiotics are discharged into the environment as metabolites or in their original state, causing pollution to water bodies, which is a serious issue. In this study, a novel nanocomposite adsorbent MIL-53/D201 was successfully prepared by hydrothermal synthesis. This approach overcomes the disadvantage of easy dissociation of MOF material in the water phase and realizes the efficient removal of antibiotic azlocillin sodium in water. The crystal morphology and basic structure of the composites were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy scattering spectroscopy (EDS), and specific surface area and porosity analyzer (BET). The results showed that MIL-53 was successfully synthesized in situ in D201. The results of adsorption experiments show that the maximum saturated adsorption capacity of the composite is 122.3 mg/g when the dosage of the composite is 1.0 g/L. Compared with pure MIL-53 material, the composite material exhibits greater stability and efficient adsorption performance for target pollutants at different pH values. The adsorption process accords with the quasi-second-order kinetic adsorption model and Langmuir adsorption isothermal model. After five cycles of adsorption and desorption, the removal rate of MIL-53/D201 to azlocillin sodium was still above 87%.
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
CHEMICAL ENGINEERING JOURNAL
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2017
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IF 6.216
Xuzeng Wang,Ning Zhuo,Change Fu,Ziqi Tian,Haige Li,Jialei Zhang,Wei Wu,Zhen Yang,Weiben Yang
A new nanocomposite adsorbent ZIF-67/D201, in which nanocrystalline ZIF-67 were immobilized inside the networking pores of a commercial polystyrene anion exchanger D201 by an alternate deposition method, with high capacity and enhanced selective affinity toward benzotriazole (BTA) was fabricated and characterized. ZIF-67/D201 demonstrated precise selective adsorption of BTA when benzimidazole (BMA), with very similar chemical structure to BTA, coexisted. After the uptake of BTA, ZIF-67/D201 could be regenerated for repeated use with slight capacity loss. According to kinetics data, two diffusion steps driven by electrostatic attraction were found prior to adsorption equilibrium: a fast diffusion of the contaminant into mesopores of D201 and then a relatively slow diffusion into micropores of ZIF-67. The underlying mechanism for the enhanced selective adsorption was revealed by spectral analysis and density functional theory (DFT) calculations. Three sorts of interactions (coordination, electrostatic attraction and π-π interaction) contributed to the fixing of contaminants. Among them, coordination was the predominant effect. For each sort of interaction, the binding energy of adsorbent-BTA was always larger than that of adsorbent-BMA, which was the intrinsic reason of the high selectivity in molecular level. The above results provided a strategy for precise separation of components with similar structures in water.
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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2023
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IF 15.1
Wenjing Chen,Huan Tang,Han Li,Yu Zhao,Xiaozhi Wang,Jiachao Chen,Zhihui Chen,Yaxian Zhu,Wenlan Yang
Fluoride contamination is a serious problem of global concern, and water decontamination from fluoride remains an imperative but also a challenging task. Recently, Ce-Fe bimetal oxyhydroxides (CFBOs) nanoparticles of sufficient hydroxyl group and high reactivity have exhibited unique advantages for specific fluoride elimination. Unfortunately, they are difficult to apply directly in scale-up water treatment due to their ultrafine nature. Herein, we fabricated a novel polymer-based Ce-Fe bimetal oxyhydroxides nanocomposite, i.e., CFBOs@201, by co-precipitation of Ce/Fe oxides nanoparticles inside a porous polystyrene anion exchanger D201. The material characterization results confirmed that CFBOs were successfully immobilized inside the pores of D201 with nanoscale and micro crystalline nature, and the shielding effect of the host D201 significantly improved the chemical stability of CFBOs against pH variation (3–12). As compared with cerium and ferric (hydr)oxides nanocomposites (HCO@201 and HFO@201) and its host D201, CFBOs@201 exhibited superior capacity and better selectivity for fluoride adsorption. Thanks to the inner-sphere complexation between immobilized CFBOs and fluoride, the concomitant competing anions exerted negligible effect on the defluoridation efficiency of CFBOs@201. Fluoride uptake onto CFBOs@201 agreed well with the pseudo-second-order kinetic model and the Langmuir isotherm model, and the calculated maximum adsorption capacity was 65.99 mg/g. The exhausted CFBOs@201 could be efficiently regenerated by a simple alkaline treatment for cyclic utilization with constant defluorination performance. Fixed-bed assays demonstrated that the encapsulating of CFBOs nanoparticles enhanced the effective treatment capacity of CFBOs@201 by 10–12 times over the host D201 irrespective of whether synthetic wastewater or mine drainage was the feeding solution. The above results verified that CFBOs@201 is a new kind of efficient defluoridation adsorbent with practical application prospect.
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 PHYSICS LETTERS
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2022
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IF 2.719
Sijing Zeng,Dengjie Zhong,Yunlan Xu,Nianbing Zhong
D201@S-nZVI was synthesized to remove Cr(VI) from aqueous solution. Batch experiments demonstrate it has excellent removal performance, recycling performance and longevity. Its removal efficiency and maximum adsorption capacity reaches 89.67% and 137.35 mg·g −1 for 100 mg·L −1 Cr(VI) solution, respectively. This is because S-nZVI (nZVI@FeS x ) has a core-shell structure. The FeS x layer prevents the leaching of iron and has excellent reduction and electron transport capability. In addition, the functional groups of D201 can electrostatically attract Cr(VI), and its unique skeleton structure well disperses S-nZVI. The adsorption is a spontaneous exothermic process. This research provides an effective remediation material for Cr(VI) wastewater.
研究领域:
环境科学
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材料科学
✓ 已验证
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
Shen Zhang,Wencai Cheng,Congcong Ding,Ze Qiu,Junwen Tan,Xirui Lu,Jun Wen,Hao Li
Developing an efficient uranium enrichment process for large-scale eluates from marine-tested fibers is crucial for filling the gap in the downstream of seawater uranium extraction. Alkaline elution of 10 kg real marine-tested fibers yielded 33 L of clear eluate after pretreatment, where uranium existed mainly as [UO 2 (CO 3 ) 2 ] 2− , [UO 2 (CO 3 ) 3 ] 4− , and [UO 2 (O 2 )(CO 3 ) 2 ] 4− species with a concentration of 11.98 mg/L, while magnesium concentration was up to 352.48 mg/L.MIP analysis selected D201 resin with more and larger pores, which showed better uranium adsorption due to a maximum electrostatic potential of 114.93 kcal/mol via simulation. 1 kg of D201 resin was used in a self-developed ion exchange equipment (maximum 100 L eluate per run) for concentration and purification. After 5 days of enrichment, 3 L of uranium concentrate was obtained, with uranium concentration increased to 121.48 mg/L and magnesium reduced to 14.9 mg/L. Ammonia water was added to the concentrate for precipitation, collecting 1112.45 mg of uranium product. The uranium precipitation rate was 99.27 %, and that of magnesium was only 31.1 %. The overall enrichment efficiency reached 93.13 % for uranium. ICP results showed the uranium mass fraction in the product was 33.1 %. TI-MS results indicated the U-235 abundance (≈0.72 %) was consistent with natural levels, and U-234 abundance (0.0064 %) was, slightly higher than natural, but still qualified it as natural uranium. This study provides an innovative enrichment process and theoretical support for efficient downstream uranium recovery in seawater uranium extraction.
研究领域:
核工程
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环境化学
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材料科学
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化学工程
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海洋科学
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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）