APPLIED SURFACE SCIENCE
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2022
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IF 7.392
Wenlan Ji,Xinyu Miao,Tian C. Zhang,Yuan Wang,Shaojun Yuan
The elimination of arsenic pollution has attracted increasing concerns due to its toxicity and severe carcinogenicity. Herein, we proposed an in-situ crystal growth strategy without surfactant to fabricate MIL-88B uniformly anchored on the surface of MnO 2 /GAC (MIL-88B/MnO 2 /GAC). Such innovative MIL-88B/MnO 2 /GAC nanostructured composites not only exhibited the synergetic functions of simultaneously oxidizing As(III) and adsorbing the generated As(V), but also effectively reduced the cost of metal–organic frameworks (MOFs) adsorbents. Impressively, the as-prepared sample achieved remarkably boosted As(III) removal capacity of 15.13 mg g −1 compared to 4.1 mg g −1 of MnO 2 /GAC composite and 2.1 mg g −1 of GAC , which was mainly ascribed to the synergistic effect between the excellent adsorption abilitiy of MIL-88B and oxidation property of MnO 2 /GAC. Owing to the unique construction and properties, the constructed MIL-88B/MnO 2 /GAC composites presented a desirable As(III) removal ability under a wide pH scope of 2 to 10. Moreover, the possible mechanism of the synergistic removal over MIL-88B/MnO 2 /GAC was elucidated by X-ray photoelectron spectroscopy (XPS), electron spin resonance (ESR) and radical trapping experiment. This work not only offers a superior bifunctional catalyst for high-efficient removal of arsenic, but also provides a new perspective for rational construction of MOF derivatives for their further applications.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2016
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IF 5.31
Xiao Ge,Juntao Liu,Xiangyang Song,Guozhong Wang,Haimin Zhang,Yunxia Zhang,Huijun Zhao
The hierarchical flower-like iron containing γ-MnO 2 hollow microspheres assembled by ultrathin nanosheets have been successfully fabricated via a facile one-step co-precipitation route in the absence of additional templates or surfactants. Structural characterization show that iron element is uniformly incorporated into γ-MnO 2 framework, and no segregated iron oxide appears. The resulting iron containing MnO 2 hollow microspheres exhibit a noticeable enhanced performance for As(III) removal compared to that of the undoped counterparts, accompanied by 102.84 mg/g of the saturated removal capacity towards As(III). The excellent performance for the arsenic removal may be attributed to the unique structural characteristics of highly accessible surface and fully exposed active sites inherited from the hierarchical iron containing γ-MnO 2 samples. The co-existence of oxidation and adsorption is another key factor for the improvement of As(III) removal efficiency, in which manganese dioxide is mainly responsible for oxidizing As(III) to As(V) and ferrous species may serve to the adsorption of the generated As(V), as evidenced by X-ray photoelectron spectroscopy (XPS) analysis. Importantly, the composites exhibit an excellent regenerative ability over three cycles without a significant decrease in its removal efficiency towards As(III). Furthermore, the relatively large micrometer-scale particles can be easily separated by filtration, accompanied by fewer secondary contaminants risks than nanoparticles. Therefore, the fabricated hierarchical Fe-containing γ-MnO 2 hollow spheres in the present study will be an excellent candidate for the arsenic transformation and removal from the contaminated water based on the synergistic effects of effective oxidizing and adsorptive performance, good regeneration together with the convenient separation.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2020
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IF 10.652
Kun Wu,Meng Wang,Angzhen Li,Zixuan Zhao,Ting Liu,Xiaodan Hao,Shengjiong Yang,Pengkang Jin
Mn-oxide-containing adsorbents have shown outstanding performances for the removal of As(III) through an “oxidation-adsorption” process. In this study, a new adsorbent of Fe-Mn-Cu ternary oxide (FMCTO) was fabricated to improve the redox reaction rate and to enhance the recovery of oxidative ability. FMCTO exhibited a stronger ability for As(III) removal than most of other adsorbents, because it has better oxidative capability for As(III) oxidation. The state of dynamic equilibrium for As(III) removal by FMCTO could be basically achieved within 3 h, and the As removal efficiency reached 98.9% at time = 24 h. The Langmuir As adsorption capacity of FMCTO was determined to be 204.8 mg/g. The As(III) removal efficiency of FMCTO was further boosted by 7% through oxygen gas aeration and decreased by 19% with nitrogen gas in the ambient during the first 3 h, indicating the positive effect of oxygen on As(III) oxidation. EPR and UV spectra methods were used to confirm the generation of superoxide radical (O 2 − ) and the enhanced production of Mn(III) soluble species on FMCTO surfaces, thus achieving a better As(III) oxidation performance. The XPS analysis results showed that the electron transfer from Cu(I) to Mn(IV) could improve the stability of Mn(III) within FMCTO. Meanwhile, Mn(II) ions could be oxidized to Mn(III) by O 2 − . Hence, the formation of a redox cycle between Mn(II) and Mn(III) along with the production of O 2 − plays a vital role in the upgraded As(III) removal mechanisms. This study provides new insights into the promotion of the capability of Mn-containing adsorbents for achieving the improved removal of As from As(III)-contaminated water.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2021
·
IF 10.588
Huimin Hu,Qiwu Zhang,Chao Wang,Min Chen,Mengfei Chen
Iron manganese oxide resources are widely derived from the geological structure , and their combinations play an important role in the migration and transformation of arsenic. Iron oxide and manganese oxide exist generally in a mixed state in Fe-Mn oxides synthesized via the well studied co-precipitation methods using potassium permanganate and manganese/iron sulfates. Herein, a newly designed Fe-Mn-O compositing oxide with Fe-MnO 2 , Mn-Fe 2 O 3 , (Fe 0.67 Mn 0.33 )OOH solid solution and FeOOH as the main components, simply through solvent-free mechanical ball milling pyrolusite (MnO 2 ) and ferrihydrite (FeOOH) together has been reported. Atomic-scale integrations by doping Fe and Mn with each other were detected and an adsorption-oxidation bifunctionality was achieved, where Fe-doped MnO 2 served as oxidizer for As(III) and amorphous/ground FeOOH acted as adsorbent first for As(III) and then As(V) from the oxidization. The maximal adsorption for As(III) could reach 44.99 mg/g and over 82.5% of As(III) was converted to As(V). More importantly, high removal ability of arsenic worked in a wide pH range of 2–10.5%, and 87.2% of its initial adsorption-oxidation capacity could be kept even after 5-cycles reuse for treating 20 mg/L As(III) with a dosage at 1 g/L. Together with the enhanced adsorption capacity by the milled FeOOH, surface electron transfer efficiency of the developed Fe-MnO 2 surrounded with Mn-Fe 2 O 3 has been studied for the first time to understand the oxidization effect to As(V). Besides the environment-friendliness of ball milling method, the prepared sample is quite stable without noticeable metal release into solution. Mechanism studies of arsenic removal by the as-prepared Fe-Mn-O oxide provide a new direction for improving the oxidation efficiency of MnO 2 to As(III) based on the widely available cheap Mn and Fe oxides, contributing to the development of advanced oxidization process in the treatment of waste water.
研究领域:
环境科学
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材料科学
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水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）