一株胞外聚合物产生菌的筛选及其EPS对Pb2+的吸附研究

The Screening of a Bacterial Strain Producing Extracellular Polymeric Substances and a Study on Its Adsorption of Pb2+

从活性污泥中分离到1株产胞外聚合物（EPS）的菌株C2,经16S rDNA基因序列分析表明,该菌株属于克雷伯氏菌属（Klebsiella sp.）。考察了pH值、初始Pb^2＋浓度及EPS投加量对EPS吸附Pb^2＋能力的影响,并采用傅立叶变换红外光谱来初步探讨吸附Pb2＋的机理。结果表明,在pH值为5.0时,EPS对Pb^2＋有很强的吸附能力,吸附率随着初始Pb^2＋浓度的减小而增大,随着EPS投加量的增大而增大。红外光谱分析表明,羟基、氨基和羰基在Pb^2＋吸附过程中起主要作用。

s A bacterial strain C2 producing extracellular polymeric substances （EPS） was isolated from activatedsludge, and identified as Klebsiella sp. by its 16S rDNA sequence analysis. The influences of pH value, initial divalent lead ion concentration and dosage of EPS on the adsorption of Pb^2＋ were also studied. The mechanism of adsorbing Pb^2＋ by EPS was preliminarily explored by means of Fourier transform infrared （FTIR） spectrometry. Results showed that the optimum pH value for adsorption of Pb^2＋ by EPS was 5.0. The adsorption rate would rise with the reducing initial Pb^2＋ concentration and the increasing dosage of EPS. The infrared spectrometric analysis indicated that the groups of carboxyl, amino and carbonyl played key roles in the process of adsorbing divalent lead ion.