中國有色金屬學報(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 24 No. 3 March 2014 |
（1. School of Chemistry and Chemical Engineering, Guangxi University for Nationalities, Nanning 530008, China;
2. Guangxi Key Laboratory of Chemistry and Engineering of Forest Products, Nanning 530008, China;
3. Key Laboratory of Chemical and Biological Transforming Process of Guangxi Higher Education Institutes,
Nanning 530008, China）
Abstract:Sawdust xanthate modified with ethanediamine was used for the removal of Cu(II) and Ni(II) from aqueous solution. The influence of various operating parameters such temperature and adsorbent dosage on the adsorption isotherms of modified sawdust was investigated. Thermodynamic parameters, namely Gibbs free energy (？GΘ), enthalpy (？HΘ) and entropy (？SΘ) of Cu(II) and Ni(II) adsorption process were calculated, showing that the adsorption is a spontaneous and exothermic process. The modified extended Langmuir equation approaches provide excellent prediction of the binary adsorption. In single and binary systems, the overall adsorption data were best described by the pseudo-second order kinetic model, then the calculated values of activation energy of Cu(II) and Ni(II) adsorption process were 59.12 and 55.92 kJ/mol respectively. The results show that the affinity of each metal ion onto the modified sawdust surface is influenced by the presence of the other one.
Key words: copper; nickel; adsorption; modified sawdust
