1. Few-layered boron nitride nanosheets as superior adsorbents for the rapid removal of lead ions from water.
- Author
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Liu, Tao, Li, Yulian, He, Junyong, Zhang, Kaisheng, Hu, Yi, Chen, Xifan, Wang, Chengming, Huang, Xingjiu, Kong, Lingtao, and Liu, Jinhuai
- Subjects
BORON nitride ,NANOSTRUCTURED materials ,CHEMICAL bonds ,ADSORPTION kinetics ,ADSORPTION isotherms - Abstract
Newly few-layered boron nitride (BN-550) nanosheets were developed by a low-temperature synthesis method, which was used to rapidly and efficiently adsorb lead ions (Pb
2+ ). The samples were characterized by using XRD, FT-IR, EELS, SEM, TEM, AFM and XPS, revealing that it possessed the large specific surface area (696 m2 g−1 ), ultrathin sheet structure (1.2 nm thickness), and abundant chemical bonds as multiple adsorption sites. The adsorption properties showed that higher adsorption capacity (845 mg g−1 ) for lead ions and less equilibrium time (15 min) than many adsorbents reported at present. The adsorption kinetics and isotherms of BN-550 belonged to the pseudo-second-order model and Langmuir model, respectively. The easy recyclability and stability of BN-550 were verified by the experiments regeneration and pH. Interference experiments indicated that the adsorbents were strong affinity for Pb2+ under the interference of other heavy metal ions such as Ni2+ , Cu2+ , and Cd2+ ions (their adsorbing capacity individually are 201, 402, and 312 mg g−1 ). The XPS and FT-IR analysis revealed that the excellent adsorption performances for Pb2+ attributed to the chemical binding reactions with the numerous surface functional groups, such as the strong B-O-Pb interactions and -NH2 ···Pb complex. The threshold value of Pb2+ removal on BN-550 nanosheets was 1080 mL g−1 when Pb2+ concentration was 50 mg L−1 in adsorption column. The unique characteristics render ultrathin nanosheets highly promising as an ideal candidate for the removal of lead ions. [ABSTRACT FROM AUTHOR]- Published
- 2019
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