Indexed by:期刊论文

Date of Publication:2018-02-01

Journal:JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS

Included Journals:SCIE、EI、Scopus

Volume:83

Page Number:192-203

ISSN No.:1876-1070

Key Words:CQDs; 3D porous structure; Boron; Selective adsorption; Oxygen-rich groups

Abstract:The 3D porous CQDs/LDHs have been synthesized using CQDs as structure-directing agent to adsorb boron(III) from aqueous solution. Characteristic results showed that the prepared CQDs/LDHs have high adsorption capacity and selectivity. FTIR and XPS spectra revealed that CQDs/LDHs possessed more oxygen-containing groups than LDHs. BET data revealed that CQDs/LDHs had a specific surface area of 186 m(2)/g, which is twice larger than LDHs of 91.6 m(2)/g. Effects of the temperature, pH and boron(III) concentration on adsorption performance of boron(III) were investigated. The results showed that the maximum adsorption capacity of 19.5 mg/g on CQDs/LDHs was obtained when the initial boron(III) concentration is 20 mg/L at pH 8.5. In the competitive adsorption system, the removal rate of CQDs/LDHs toward boron(III) can reach to 89.7%, which is three times bigger than raw LDHs. Adsorption isotherm and kinetics studies revealed that boron(III) adsorption process was well-described by Langmuir isotherm and pseudo-second-order kinetic model, respectively. Adsorption and characterization data proved that the adsorption mechanism of boron(III) is a complex process, including anion exchange and oxygen-containing group adsorption. This work not only gives a new way to synthesize 3D porous material but also provides a potential material to selectively adsorp boron(III). (C) 2017 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.