title: Characteristics and mechanisms of Cu(II) biosorption by disintegrated aerobic granules.
abstract: Disintegrated aerobic granules (DAG) as an effective biosorbent had great potential to remove Cu(II) from aqueous solution. The effects of solution pH value, contact time, initial Cu(II) concentration on the biosorption were investigated. Kinetic studies indicate that pseudo-second-order model with correlation coefficients of 0.9999 best fits the Cu(II) biosorption process. Investigation of the biosorption mechanisms shows that Cu(II) biosorption is associated with a significant release of Ca(II). The adsorption capacity of extracted extracellular polymeric substances (EPS) was 2.34 times as much as that of pristine DAG, indicating the significant role of EPS in adsorption. In order to determine the role of different functional groups, DAG was chemically modified to block specific functional groups and was then used in the adsorption of Cu(II). The anionic carboxyl group, was identified as the key binding site for the cationic Cu(II). Results reveal that ion exchange is the most important biosorption mechanism but other mechanisms to some extent like electrostatic interaction, involving in functional groups, also play a part.
authors.affiliation: Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, China.
authors.forename: Xin-Hua
authors.initials: XH
authors.lastname: Wang
authors.forename: Rui-Hong
authors.initials: RH
authors.lastname: Song
authors.forename: Shao-Xiang
authors.initials: SX
authors.lastname: Teng
authors.forename: Ming-Ming
authors.initials: MM
authors.lastname: Gao
authors.forename: Jian-Yuan
authors.initials: JY
authors.lastname: Ni
authors.forename: Fei-Fei
authors.initials: FF
authors.lastname: Liu
authors.forename: Shu-Guang
authors.initials: SG
authors.lastname: Wang
authors.forename: Bao-Yu
authors.initials: BY
authors.lastname: Gao
mesh_terms: D000327:Adsorption; D000332:Aerobiosis; D003300:Copper / Q000737:chemistry*; D003362:Cost-Benefit Analysis; D006863:Hydrogen-Ion Concentration; D007474:Ion Exchange; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D008956:Models, Chemical; D010316:Particle Size; D052638:Particulate Matter / Q000737:chemistry*; D012996:Solutions; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D052638:Particulate Matter; D012996:Solutions; D003300:Copper