title: From spent Mg/Al layered double hydroxide to porous carbon materials.
abstract: Adsorption has been considered as an efficient method for the treatment of dye effluents, but proper disposal of the spent adsorbents is still a challenge. This work attempts to provide a facile method to reutilize the spent Mg/Al layered double hydroxide (Mg/Al-LDH) after the adsorption of orange II (OII). Herein, the spent hybrid was carbonized under the protection of nitrogen, and then washed with acid to obtain porous carbon materials. Thermogravimetric analysis results suggested that the carbonization could be well achieved above 600°C, as mass loss of the spent hybrid gradually stabilized. Therefore, the carbonization process was carried out at 600, 800, and 1000°C, respectively. Scanning electron microscope showed that the obtained carbon materials possessed a crooked flaky morphology. Nitrogen adsorption-desorption results showed that the carbon materials had large BET surface area and pore volume, e.g., 1426 m(2)/g and 1.67 cm(3)/g for the sample carbonized at 800°C. Moreover, the pore structure and surface chemistry compositions were tunable, as they were sensitive to the temperature. Toluene adsorption results demonstrated that the carbon materials had high efficiency in toluene removal. This work provided a facile approach for synthesizing porous carbon materials using spent Mg/Al-LDH.
authors.affiliation: Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangdong Provincial Key Laboratory of Mineral Physics and Material Research & Development, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Minwang
authors.initials: M
authors.lastname: Laipan
authors.affiliation: Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangdong Provincial Key Laboratory of Mineral Physics and Material Research & Development, Guangzhou 510640, China. Electronic address: zhurl@gig.ac.cn.
authors.forename: Runliang
authors.initials: R
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangdong Provincial Key Laboratory of Mineral Physics and Material Research & Development, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Qingze
authors.initials: Q
authors.lastname: Chen
authors.affiliation: Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangdong Provincial Key Laboratory of Mineral Physics and Material Research & Development, Guangzhou 510640, China.
authors.forename: Jianxi
authors.initials: J
authors.lastname: Zhu
authors.affiliation: School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia.
authors.forename: Yunfei
authors.initials: Y
authors.lastname: Xi
authors.affiliation: School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia.
authors.forename: Godwin A
authors.initials: GA
authors.lastname: Ayoko
authors.affiliation: Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangdong Provincial Key Laboratory of Mineral Physics and Material Research & Development, Guangzhou 510640, China.
authors.forename: Hongping
authors.initials: H
authors.lastname: He
keywords: Calcined layered double hydroxide; Dye effluents treatment; Porous carbon material; Spent adsorbent recycling; Volatile organic compound