Thermodynamics and kinetics of adsorption of cu (II)‎ from aqueous solutions onto multi-walled carbon nanotubes

Abstract EN

Release of heavy metals into water as a result of industrial activities may pose a serious threat to the environment.

The objective of this study is to assess the uptake of Cu2+ from aqueous solutions onto multi-walled carbon nanotubes (MWCNT).

The potential of the t-MWCNT to remove Cu2+ cations from aqueous solutions was investigated in batch reactor under different experimental conditions.

The processing parameters such as initial concentration of Cu2+ ions, temperature, and adsorbent mass were also investigated.

Copper uptake was quantitatively evaluated using the Langmuir, Freundlich and Dubinin-Kaganer-Radushkevich (DKR) models.

In addition, the adsorption equilibrium was described well by the Langmuir isotherm model with maximum adsorption capacity of 12.34 mg / g of Cu2+ cations on t-MWCNT.

Various thermodynamic parameters, such as DG0, DH0 and DS0 were calculated.

The thermodynamics of Cu2+ cations adsorption onto t-MWCNT system pointed at spontaneous and endothermic nature of the process.

Using the second-order kinetic constants, the activation energy of adsorption (Ea) was determined as 27.187 kJ / mol according to the Arrhenius equation.