Kinetic Study of an Effective Pb(II) Transport through a Bulk Liquid Membrane Containing Calix[6]arene Hexaester Derivative as a Carrier

Abstract

The article describes transport of Pb(II) through bulk liquid membrane (BLM) containing calix[6]arene hexaester derivative (1) as a carrier. The effect of various parameters such as temperature, carrier concentration, stirring speed and type of solvent on the Pb(II) transport efficiency of the carrier through BLM was evaluated. The activation energy values for the extraction and re-extraction were found as 56.33 kJ mol⁻¹ and 14.79 kJ mol⁻¹, respectively. These values demonstrate that the process is diffusionally controlled by Pb(II). Observations indicate that the membrane entrance and exit rate constants (k₁, k₂) increase with increasing stirring speed as well as carrier concentration and decrease with increasing temperature. The effect of solvent on k₁ and k₂ was found to be in the order of CH₂Cl₂ > CHCl₃ > CCl₄.

Keywords:

• bulk liquid membrane
• calixarene
• kinetic parameters
• Pb(II) toxicity

ACKNOWLEDGEMENTS

We thank Prof. Dr. Mustafa Ersoz (Selcuk University, Department of Chemistry, Kampus, 42031 Konya, Turkey) for facilitating necessary Laboratory equipments. The financial assistance from Higher Education Commission Islamabad (No Ps4-086/HEC/Sch/2007) and the National Centre of Excellence in Analytical Chemistry, University of Sindh, Jamshoro is also deeply appreciated.

Notes

ϵ₀ dielectric constant (20°C).

n _D refractive index (20°C).

μ dipole moment (D).

η viscosity (cP).

V _m molar volume (M⁻¹).