Study of the Factor Affecting the Adsorption of Copper Ion by an Iraqi Clay

Abstract

In this research work, the efficiency of a local clay (collected from Al-Kadia area of Mosul city in the north part of Iraq) to adsorb the copper (II) ion from aqueous solution was investigated. The experiments were carried out as a batch method. The factors affecting the removal efficiency such as; contact time, initial concentration, initial pH solution and particle size of adsorbent are studied. The results showed that, the increase of initial concentration increases the amount of adsorbed metal ion but decreases the adsorption efficiency. The amount of copper (II) ion increases rapidly with the increase of pH from 2 to 5, however there was little change within the pH range between (5-8). The increase of the surface area (decrease of particle size) was accompanied by increase in removal efficiency.

The adsorption is also conducted at various temperatures (15-55 °C) and at different initial concentration (10-70 mg/L). The thermodynamic functions are estimated.

Kinetic study of adsorption of copper (II) ion on the clay surface is carried out by applying the first order integrated equation of the reversible reaction. The adsorption equilibrium, adsorption and desorption rate constants are calculated at different temperature. The activation energies and the thermodynamic functions of activation of the forward and backward processes are estimated.