Electrical Removal Behavior of Carbon Nanotube and Carbon Nanofiber Film in CuCl2 Solution: Kinetics and Thermodynamics Study

The kinetics, thermodynamics, and isotherms during electrical removal of Cu2+by carbon nanotube and carbon nanofiber (CNT-CNF) electrodes in CuCl2solution were studied under different solution temperatures, initial Cu2+concentrations, and applied voltages. The result shows that Langmuir isotherm can describe experimental data well, indicating monolayer adsorption, and higher Cu2+removal and rate constant are achieved at higher voltage, lower initial Cu2+concentration, and higher solution temperature. Meanwhile, the thermodynamics analyses indicate that the electrical removal of Cu2+onto CNT-CNF electrodes is mainly driven by a physisorption process.