|
Effect of norfloxcian on sorption of copper onto humic acid |
Received:December 15, 2016 |
View Full Text View/Add Comment Download reader |
KeyWord:copper;norfloxcian;humic acid;kinetics;pH;thermodynamics |
Author Name | Affiliation | E-mail | LIU Juan | Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China University of Chinese Academy of Sciences, Beijing 100049, China | | ZHAO Ling | Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China University of Chinese Academy of Sciences, Beijing 100049, China | | WANG Hui | Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China University of Chinese Academy of Sciences, Beijing 100049, China | hwang@issas.ac.cn | DONG Yuan-hua | Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China University of Chinese Academy of Sciences, Beijing 100049, China | |
|
Hits: 2836 |
Download times: 3237 |
Abstract: |
Effects of norfloxcian (NOR) on the kinetics, thermodynamics and adsorption isotherms of copper onto humic acid (HA) were investigated by batch equilibrium studies according to OECD Guideline 106. Results showed that the pseudo-second-order model was the best one to describe the adsorption kinetics of Cu2+ onto HA not only in the absence of NOR but also in the presence of NOR (R2>0.99). However, the presence of NOR suppressed copper adsorption rate on the HA. When pH was between 3.0 and 5.5, adsorption isotherms of Cu2+ onto the HA were well fitted with the Langmuir equation with or without NOR. The presence of NOR suppressed the adsorption amount of Cu2+ onto the HA was also observed. On the one hand, it is ascribed to the formation of positively charged complexes of copper and NOR that had lower affinity to the HA; on the other hand, there is competition between NOR+ and Cu2+ for surface sites of HA. The adsorption of Cu2+ increased with increasing pH in the absence and presence of NOR. It proves that the Cu2+ and complexes of copper and NOR adsorption to HA by cation exchange and electrostatic attraction. The presence of NOR enhanced the values of enthalpy and degree of disorder during the process of copper sorption onto HA based on the results of thermodynamics experiment. |
|
|
|