title: Heteroatoms doped porous carbon derived from hydrothermally treated sewage sludge: Structural characterization and environmental application.
abstract: The heteroatoms (N and S) doped porous carbons (HAPCs) were prepared from sewage sludge by hydrothermal carbonization and chemical activation for the first time. The porous structures and surface properties of HAPCs were characterized by multiple techniques including SEM-EDS, TEM, BET, XRD, Raman spectroscopy and Boehm's titration. The resultant materials were showed to be naturally N and S dual-doped porous carbons (HAPCs), especially for HAPCHCl+HFobtained by HCl-HF-washing, which was typical 3D hierarchically porous structure with abundant mesopores as well as big pore diameter. Then the performance of HAPCHCl+HFon AO7 removal was determined through Response surface methodology. The results showed the adsorption behavior obeyed Langmuir isotherm model and the maximum adsorption capacity was up to 440.53 mg g-1at 25 °C. Kinetics study revealed that the adsorption followed pseudo second-order kinetic and intra-particle diffusion was the main control step. The high removal rate of AO7 was ascribed to the unique properties of HAPCHCl+HF. The great Vmesand big pore diameter facilitated the diffusion of AO7 into the intra surface of particle. Meanwhile, the basic groups and doping of N and S made HAPCHCl+HFsurface had positive charges, then strong π-π stacking interaction and electrostatic attraction contributed to the highly effective adsorption. This study indicated hydrothermal carbonization coupled with chemical activation was a cost-effective approach to prepare efficient heteroatoms doped porous carbon from sewage sludge towards azo dye contaminated wastewater treatment.
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Li
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Nana
authors.initials: N
authors.lastname: Peng
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Qianqian
authors.initials: Q
authors.lastname: Lang
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Xia
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Gai
authors.affiliation: Analysis and Testing Center, Inner Mongolia University for the Nationalities, Tongliao 028000, China.
authors.forename: Qingfu
authors.initials: Q
authors.lastname: Zheng
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address: zgliu@rcees.ac.cn.
authors.forename: Zhengang
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000327:Adsorption; D002244:Carbon; D004396:Coloring Agents; D007700:Kinetics; D016062:Porosity; D012722:Sewage
chemical_list: D004396:Coloring Agents; D012722:Sewage; D002244:Carbon
keywords: Dye; Heteroatom-doping; Hydrothermal carbonization; Porous carbon; Response surface methodology; Sewage sludge