Calix[4]arene Derivative as Copper(II) Carrier in a Bulk Liquid Membrane: A Kinetic Study.

A bulk liquid membrane (BLM) experiment was carried out to check the Cu(II) transport efficiency of p-morpholinomethylcalix[4]arene (1) which was used as carrier. Liquid/liquid extraction experiments were also carried out to check the extraction and decomplexation efficiency of carrier 1. It has been observed that the maximum amount of Cu(II) was transported at pH = 12. The mass transfer of Cu(II) was analyzed on the basis of kinetic laws of two consecutive irreversible first order reactions. Thus, the kinetic parameters studied for the transport of Cu(II) were k1, k2, . BLM study revealed that Cu(II) transport increase with increase in concentration of carrier 1 from 1 × 10−5 to 1 × 10−4 M, rise in temperature from 298 to 308 K and at high stirring speed from 90 to 800 rpm. The effect of binary solvents on Cu(II) transport through BLM has also been studied. The values of k1, k2, decrease in the order of dichloromethane-hexane > dichloromethane-diethylether > dichloromethane > dichloromethane-ethylacetate > chloroform. However, dichloromethane was proved as a stable BLM solvent. The activation energy value for the extraction and re-extraction was found as 31.52 and 8.08 kJmol−1, respectively. These values demonstrate that Cu(II) transport is a diffusion controlled process. Thus, 1 was found to be an efficient carrier for Cu(II) transport through BLM. [ABSTRACT FROM AUTHOR]