农业环境科学学报2012，Vol.31Issue(5)：1021-1027,7.
活性污泥胞外聚合物(EPS)对Pb2+吸附性能的研究
The Characteristics Study on Adsorption of Pb2+ by Extracellular Polymeric Substances from Activated Sludge
摘要
Abstract
The adsorption property on lead ions was studied using extracellular polymeric substancest EPS) as adsorbent, which was extracted from activated sludge. The parameters affected the adsorption rate were investigated and optimized via a response surface method, such as solution pH, dosage of EPS and temperature. The thermodynamic and kinetic absorption characteristics of EPS for lead ions were also dis-cussed.Results showed that the optimal adsorption condition was at 35 ℃, pH4.2 and m(EPS):m(Pb2+) was 2.5:1. Under the optimum condition, the actual adsorption efficiency of lead ions by EPS could reach 89.16%. The absorption isotherm of lead ions by EPS could be described by both Langmuir and Freundlich model. But the Langmuir model was more accurate than the Freundlich model.According to the Langmuir equation, the maximum adsorption amount al the temperature of 20, 30 and 40 ℃can be expected to reach 0.922 9, 1.012 9, 1.119 1 mg · mg"-1when adsorption equilibrium, respectively. The adsorption amount increased with the rise of temperature showed that temperature was beneficial to the adsorption process and the process of adsorption of lead ion by EPS was an endothermic process.In addition, the adsorption process fitted well with pseudo-second order equations.The adsorption equilibrium could be reached at the time of 240 min with the maximum theoretical absorption amount of 0.45 mg·mg-1.关键词
活性污泥/胞外聚合物(EPS)/吸附/重金属/响应面Key words
activated sludge/extracellular polymeric substances/adsorption/heavy metal/response surface methodology分类
资源环境引用本文复制引用
陶玉贵,倪正,王文强,秦昌云,徐艳秋..活性污泥胞外聚合物(EPS)对Pb2+吸附性能的研究[J].农业环境科学学报,2012,31(5):1021-1027,7.基金项目
安徽省科技攻关计划面上项目(08010302169) （08010302169）
安徽省高校省级自然科学研究重点项目(KJ2012A034) （KJ2012A034）
