Characteristics and mechanisms of Cu(II) biosorption by disintegrated aerobic granules.
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.
Wang
Xin-Hua
XH
Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100, China.
Song
Rui-Hong
RH
Teng
Shao-Xiang
SX
Gao
Ming-Ming
MM
Ni
Jian-Yuan
JY
Liu
Fei-Fei
FF
Wang
Shu-Guang
SG
Gao
Bao-Yu
BY
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
D052638:Particulate Matter; D012996:Solutions; D003300:Copper