文献类型：期刊文献

英文题名：Wettability modification of pitch-based spherical activated carbon by air oxidation and its effects on phenol adsorption

作者：Liu, Chaojun[1];Liang, Xiaoyi[1];Liu, Xiaojun[1];Wang, Qin[1];Teng, Na[1];Zhan, Liang[1];Zhang, Rui[1];Qiao, Wenming[1];Ling, Licheng[1]

机构：[1]E China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China

年份：2008

卷号：254

期号：9

起止页码：2659

外文期刊名：APPLIED SURFACE SCIENCE

收录：;EI(收录号：20080711097560);WOS:【SCI-EXPANDED(收录号:WOS:000254243600016)】；

语种：英文

外文关键词：activated carbon; functional groups; wettability; adsorption; phenol

摘要：The surface chemistry of pitch-based spherical activated carbon (PSAC) was modified by air oxidation to enhance its wettability as well as adsorption properties. Changes of PSAC after modification in texture, surface chemistry and wettability were studied by different techniques including N-2 adsorption, X-ray photoelectron spectroscopy (XPS) and dynamic contact angle analyzer (DCA). Phenol adsorption characteristics in different solvents on PSAC were also investigated. When PSAC was modified under an atmosphere with 20 vol.% oxygen at 400 and 450 degrees C for 5 h, surface acidic groups increased from 0.11 to 1.22 and 1.60 meq/g, while basic groups decreased from 0.52 to 0.03 and 0.02 meq/g, respectively. After PSAC was modified, the increase of the oxygen-containing groups, especially carboxylic and phenolic ones, is responsible for the increasing of the surface acidity and the significant improvement of the wettability of PSAC. PSAC with a relatively high oxygen content provided a low adsorption capacity to phenol in aqueous solution, and the adsorption isotherms change from Langmuir class (L) to the S-shaped curve; while the solvent is changed into cyclohexane, all adsorption isotherms are type L, and the adsorption capacity to phenol increases with increasing oxygen-containing groups. Possible reasons, including the solvent effect, pi-pi dispersion and donor - acceptor interactions are discussed. (C) 2007 Elsevier B. V. All rights reserved.