Removal of an emerging pharmaceutical pollutant, sulfasalazine, by adsorption onto pomegranate peels

Abstract

The removal of an emerging pharmaceutical pollutant, sulfasalazine, which frequently detected in pharmaceutical industry wastewater as well as in drinking water, has been investigated by adsorption on a biosorbent, prepared from pomegranate peels in order to valorize food processing waste. After characterizing and determining the surface functions, morphology and textural properties of the biosorbent pomegranate peels, the effect of pollutant concentration, pH and adsorbent amount on the adsorption activity were evaluated by varying one parameter at a time. Results showed a quasi-total removal of sulfasalazine for a pH higher than 4.8, an initial pollutant concentration of 50 mg L−1 and an adsorbent mass of 0.5 g. The isotherm, kinetic and thermodynamic parameters for sulfasalazine adsorption on the biosorbent have been estimated. Results revealed that the adsorption of sulfasalazine on pomegranate peels is a homogenous monolayer, spontaneous and endothermic process following a pseudo-second-order kinetic.