期刊
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
卷 3, 期 2, 页码 1223-1232出版社
ELSEVIER SCI LTD
DOI: 10.1016/j.jece.2015.04.009
关键词
Extracellular polymeric substances; Protein; Adsorption; Heavy metal; Aerobic granular sludge
资金
- National Natural Science Foundation of China [51379010]
- Collaborative Innovation Center for Regional Environmental Quality
Extracellular polymeric substances (EPS) in aerobic granular sludge (AGS) play an important role in the removal of heavy metals. In this study, EPS with high protein content (86.8%) were extracted from AGS using a cation exchange resin extraction method. EPS exhibited large adsorption capacities for Pb(II), Cd(II) and Zn(II) of 1587.3, 1470.6 and 1123.6 mg/g respectively, as calculated by the Langmuir isotherm model. The excellent biosorption performance of EPS was closely related to the large concentrations of carboxyl (0.615 mmol/g) and hydroxyl groups (0.525 mmol/g) located on protein surfaces. FTIR and XPS analysis demonstrated that the dominant adsorption mechanism was complexation by carboxyl and hydroxyl groups. Moreover, extracted EPS, both with hydrophobic and hydrophilic groups, were found to comprise an amphiphilic material, which could also capture metal ions through electrostatic attraction and ion-exchange. Furthermore, the heavy metal ions could be efficiently desorbed from EPS under acidic conditions and reused. The study indicates that protein in EPS filled with carboxyl and hydroxyl groups is key to the heavy-metal adsorption process. The results provide basic guidance for the full utilization of EPS in AGS for bioremediation in wastewater treatment. (C) 2015 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据