β-Cyclodextrin-crosslinked polymeric adsorbent for simultaneous removal and stepwise recovery of organic dyes and heavy metal ions: Fabrication, performance and mechanisms

By Xiaomei Qin, Lan Bai, Yizheng Tan, Lei Li, Fei Song, Yuzhong Wang. Chemical Engineering Journal, 2019

147 citations recorded by the source corpus.

Abstract The currently reported adsorbents for wastewater purification generally have only limited adsorption capacity towards a single type of pollutant; few of them can simultaneously remove multiple types of pollutants from cocontaminated water with high efficiency. In this work, a kind of β-Cyclodextrin based polymeric adsorbent (PCD-VI) with an expanded “pocket” structure was created, and it exhibited excellent adsorption capacities for different kinds of pollutants, cationic rhodamine B (RB), anionic Congo red (CR) and cadmium ion (Cd(II)) in a mono-component solution. Since the “pocket effect” (composed of cavity inclusion and π-π interactions), electrostatic attraction and coordination were the dominant mechanisms for RB, CR and Cd(II) adsorption, respectively, competitive adsorption was effectively avoided in the simultaneous adsorption process. RB and Cd(II) exhibited a synergistic effect in the RB-Cd(II) binary solution; the coexisting Cd(II) showed a negligible effect on CR adsorption at lower CR concentrations (≤400 mg L−1), while the removal of Cd(II) was prominently promoted by the coexisting CR in the CR-Cd(II) binary system. More importantly, RB and Cd(II) could be recovered separately, and PCD-VI could be recycled without a serious decline in performance even after five sequential adsorption-desorption cycles in the RB-Cd(II) binary system. Our studies suggest promising strategies for fabrication and application of advanced adsorption materials in water pollution remediation.

Subfields: Organic Chemistry, Water Science and Technology

View Paper: https://www.semanticscholar.org/paper/6b9030ec1c0e51a55b02ad06a7cb9e6a3bb137df