Adsortive removal of copper from aqueous solution by agro-industrial waste adsorbent

Abstract

The objective of the present study were to convert rice straw, a by-product of rice production to a metal adsorbent and further to investigate the potential of using the adsorbent for the removal of Cu(II) ions. The rice straw was water washed and citric acid (CA) modified to enhance its nature adsorption capacity. The physical and morphological characteristics were determined, and batch adsorption studies were carried out under various operating conditions. The experimental data can be well described by Langmuir isotherm model, and kinetic studies indicated that the pseudo-second-order kinetic equation provides better correlation data. The thermodynamic studies indicated that the process changed with the rise in temperature. Therefore, CA modified rice straw (CARS) has a considerable potential as a low-cost and highly efficient adsorbent, to be a new single-use adsorbent for the removal of Cu(II) ions from wastewater.