Comparative study of arsenic removal by iron-based nanomaterials: Potential candidates for field applications
Comparative study of arsenic removal by iron-based nanomaterials: Potential candidates for field applications
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DOI：
10.1016/j.scitotenv.2020.142914
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发表时间：
2021-04-10
影响因子：
9.8
通讯作者：
Bezbaruah, Achintya N.
中科院分区：
文献类型：
--
作者：
Das, Tonoy K.;Bezbaruah, Achintya N.
比较了氧化石墨烯负载的磁铁矿（GM）和氧化石墨烯负载的纳米级零价铁（GNZVI）纳米杂化物在宽pH范围（3-9）下的砷去除。虽然已经发表的工作报告了GM和GNZVI的高工艺效率，但由于实验条件不同，它们不能一对一地进行比较。每个研究小组使用不同的初始砷浓度，溶液pH值和吸附剂剂量。本研究评估了GM和GNZVI、裸磁铁矿（M）和裸纳米级零价铁（NZVI）在类似实验条件下对水溶液砷的去除。GNZVI在较宽的pH范围（3-9）内对As（III）和As（V）都更有效（>90%），而GM仅在pH 3下对As（V）有效（>90%），并且As（III）去除率在pH 9下最大接近80%。在该实验中，与其他吸附剂相比，GNZVI还表现出更好的水溶性，zeta电位为-21.02 mV。基于归一化的铁含量的砷去除表明，与裸纳米颗粒相比，纳米杂化物记录了改善的砷去除，并且GNZVI效果最好。在NZVI基纳米材料（GNZVI和NZVI）中，静电吸引作用有限，而表面络合作用在去除两种砷物种中占主导地位。在M基纳米材料（GM和M）的情况下，As（V）的去除是由静电吸引控制的，而As（III）的吸附是配体交换和表面络合。GNZVI具有现场应用于饮用水除砷的潜力。(C)2020 Elsevier B. V.保留所有权利。
Graphene oxide supported magnetite (GM) and graphene oxide supported nanoscale zero-valent iron (GNZVI) nanohybrids were compared for arsenic removal at a wide pH range (3-9). While already published work reported high process efficiency for GM and GNZVI, they cannot be compared one-on-one given the nonidentical experimental conditions. Each researcher team used different initial arsenic concentration, solution pH, and adsorbent dose. This study evaluated GM and GNZVI, bare magnetite (M), and bare nanoscale zero-valent iron (NZVI) for aqueous arsenic removal under similar experimental conditions. GNZVI worked more efficiently (>90%) in a wide pH range (3-9) for both As(III) and As(V), while GM was efficient (>90%) only at pH 3 for As(V) and As(III) removal was maximum of similar to 80% at pH 9. GNZVI also exhibited better aqueous dispersibility with a zeta potential of -21.02 mV compared to other adsorbents in this experiment The arsenic removal based on normalized iron content indicated that the nanohybrids recorded improved arsenic removal compare to bare nanopartides, and GNZVI worked the best. In NZVI-based nanomaterials (GNZVI and NZVI), electrostatic attraction played a limited role while surface complexation was dominant in removal of both the arsenic species. In case of M-based nanomaterials (GM and M), As(V) removal was controlled by electrostatic attraction while As (III) adsorption was ligand exchange and surface complexation. GNZVI has the potential for field application for drinking water arsenic removal. (C) 2020 Elsevier B.V. All rights reserved.