title: Activated carbon coated palygorskite as adsorbent by activation and its adsorption for methylene blue.
abstract: An activation process for developing the surface and porous structure of palygorskite/carbon (PG/C) nanocomposite using ZnCl2 as activating agent was investigated. The obtained activated PG/C was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (SEM), and Brunauer-Emmett-Teller analysis (BET) techniques. The effects of activation conditions were examined, including activation temperature and impregnation ratio. With increased temperature and impregnation ratio, the collapse of the palygorskite crystal structure was found to accelerate and the carbon coated on the surface underwent further carbonization. XRD and SEM data confirmed that the palygorskite structure was destroyed and the carbon structure was developed during activation. The presence of the characteristic absorption peaks of CC and C-H vibrations in the FTIR spectra suggested the occurrence of aromatization. The BET surface area improved by more than 11-fold (1201 m2/g for activated PG/C vs. 106 m2/g for PG/C) after activation, and the material appeared to be mainly microporous. The maximum adsorption capacity of methylene blue onto the activated PG/C reached 351 mg/g. The activated PG/C demonstrated better compressive strength than activated carbon without palygorskite clay.
authors.affiliation: School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei 230009, China. Electronic address: zhangxianlong94@aliyun.com.
authors.forename: Xianlong
authors.initials: X
authors.lastname: Zhang
authors.affiliation: School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei 230009, China.
authors.forename: Liping
authors.initials: L
authors.lastname: Cheng
authors.affiliation: School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei 230009, China. Electronic address: xuepingw@ustc.edu.cn.
authors.forename: Xueping
authors.initials: X
authors.lastname: Wu
authors.affiliation: School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei 230009, China.
authors.forename: Yingzhao
authors.initials: Y
authors.lastname: Tang
authors.affiliation: School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China.
authors.forename: Yucheng
authors.initials: Y
authors.lastname: Wu
mesh_terms: D000327:Adsorption; D002244:Carbon / Q000737:chemistry*; D002712:Chlorides; D017616:Magnesium Compounds / Q000737:chemistry*; D008751:Methylene Blue / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D053761:Nanocomposites; D017655:Silicon Compounds / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry; D014961:X-Ray Diffraction; D017967:Zinc Compounds
chemical_list: D002712:Chlorides; D017616:Magnesium Compounds; D017655:Silicon Compounds; D014874:Water Pollutants, Chemical; D017967:Zinc Compounds; D002244:Carbon; C016837:zinc chloride; D008751:Methylene Blue; C026325:attapulgite
keywords: Activation; Adsorption; Compressive strength; Methylene blue; Palygorskite/carbon