title: Fabrication of carbon/SiO2 composites from the hydrothermal carbonization process of polysaccharide and their adsorption performance.
abstract: In this work, carbon/SiO2 composites, using amylose and tetraethyl orthosilicate (TEOS) as raw materials, were successfully prepared by a facial hydrothermal carbonization process. The carbon/SiO2 composites were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Energy Dispersive Spectroscopy (EDS), transmission electron microscope (TEM), N2 adsorption and Thermogravimetric (TG) analysis. The composites, which were made up of amorphous SiO2 and amorphous carbon, were found to have hierarchical porous structures. The mass ratios of amylose and SiO2 and the hydrothermal carbonization time had significant effects on the morphology of the composites, which had three shapes including monodispersed spheres, porous pieces and the nano-fibers combined with nano-spheres structures. The adsorption performance of the composites was studied using Pb(2+) as simulated contaminants from water. When the mass ratio of amylose and SiO2 was 9/1, the hydrothermal time was 30h and the hydrothermal temperature was 180°C, the adsorption capacity of the composites achieved to 52mg/g. Experimental data show that adsorption kinetics of the carbon/SiO2 composites can be fitted well by the Elovich model, while the isothermal data can be perfectly described by the Langmuir adsorption model and Freundlich adsorption model. The maximum adsorption capacity of the carbon/SiO2 composites is 56.18mgg(-1).
authors: School of Marine Science and Engineering, Hebei University of Technology, Tianjin 300130, PR China; Engineering Research Center of Seawater Utilization Technology, Ministry of Education, Tianjin 300130, PR China. Electronic address: lillian09281@hotmail.com.
authors: Yinhui
authors: Y
authors: Li
authors: School of Marine Science and Engineering, Hebei University of Technology, Tianjin 300130, PR China.
authors: Kunyu
authors: K
authors: Li
authors: School of Marine Science and Engineering, Hebei University of Technology, Tianjin 300130, PR China; Engineering Research Center of Seawater Utilization Technology, Ministry of Education, Tianjin 300130, PR China.
authors: Min
authors: M
authors: Su
authors: School of Marine Science and Engineering, Hebei University of Technology, Tianjin 300130, PR China.
authors: Yanmei
authors: Y
authors: Ren
authors: School of Marine Science and Engineering, Hebei University of Technology, Tianjin 300130, PR China.
authors: Ying
authors: Y
authors: Li
authors: School of Marine Science and Engineering, Hebei University of Technology, Tianjin 300130, PR China; Engineering Research Center of Seawater Utilization Technology, Ministry of Education, Tianjin 300130, PR China.
authors: Jianxin
authors: J
authors: Chen
authors: School of Marine Science and Engineering, Hebei University of Technology, Tianjin 300130, PR China; Engineering Research Center of Seawater Utilization Technology, Ministry of Education, Tianjin 300130, PR China.
authors: Liang
authors: L
authors: Li
mesh_terms: D065966:Absorption, Physicochemical; D000688:Amylose / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry*; D015386:Hazardous Substances / Q000737:chemistry; D007700:Kinetics; D007854:Lead / Q000737:chemistry; D019216:Metals, Heavy / Q000302:isolation & purification*; D053761:Nanocomposites / Q000737:chemistry*; D009566:Nitrates / Q000737:chemistry; D016062:Porosity; D012821:Silanes / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry; D018508:Water Purification / Q000379:methods*
chemical_list: D015386:Hazardous Substances; D019216:Metals, Heavy; D009566:Nitrates; D012821:Silanes; D014867:Water; D007854:Lead; C040733:tetraethoxysilane; C017461:lead nitrate; D002244:Carbon; D012822:Silicon Dioxide; D000688:Amylose
keywords: Amylose; Carbon/SiO(2); Hydrothermal carbonization process; Pb(2+) adsorption