Adsorption kinetics and desorption of Cu(II) and Zn(II) from aqueous solution onto humic acid.
The adsorption kinetics of Cu(II) and Zn(II) from aqueous solution onto humic acid (HA) were investigated under different conditions. The results showed that HA was particularly effective for adsorbing heavy metals and that the effective pH range was above 6. The adsorption force was not single and dependent on solution pH. The experimental data were found to comply with the pseudo-second-order kinetic model with adsorption capacity, q(e cal) more close to the measured results. Increment of initial adsorbate concentration (1-4 mg/L) and temperature (283-303 K) are both favorable to adsorption process. Based on the desorption experiments, it is further indicated that the main adsorption force was complexation effect between organic ligands of HA surface and metal ions and the percentage of desorption is 50% for Cu and 30% for Zn, respectively.
Li
Ying
Y
Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shanda South Road No. 27, Shandong University, Jinan, Shandong 250100, China.
Yue
Qinyan
Q
Gao
Baoyu
B
D000085:Acetates / Q000737:chemistry; D000327:Adsorption; D002614:Chelating Agents / Q000737:chemistry; D003300:Copper / Q000737:chemistry*; D004492:Edetic Acid / Q000737:chemistry; D006812:Humic Substances / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D015233:Models, Statistical; D012996:Solutions; D013696:Temperature; D013816:Thermodynamics; D014867:Water; D015032:Zinc / Q000737:chemistry*
D000085:Acetates; D002614:Chelating Agents; D006812:Humic Substances; D012996:Solutions; D014867:Water; D003300:Copper; D004492:Edetic Acid; D015032:Zinc; C018824:ammonium acetate