Use of sweet ‘Pêra’ peel as an adsorbent in the treatment of textile effluents

Abstract

he disposal of industrial wastewater into aquatic bodies without proper treatment can cause severe damage to the environment and human health. he objective of this study was to perform the drying of the sweet orange (Citrus sinensis L. Osbeck) peel cultivar Pêra and evaluate the viability of its use as biosorbent in the removal of a direct dye. Drying was carried out in an oven with air circulation at temperatures of 60 and 80 ºC. he mathematical models of Page, Henderson and Pabis, Logarithmic, Midilli and Two-term exponential were itted to the moisture data as a function of time. he material was characterized by scanning electron microscopy, point of zero charge, and infrared spectroscopy. In the adsorption study, a complete 24 factorial design was used to analyze the inluence of mass, initial concentration, solution pH and contact time on adsorbed quantity (qt) and removal percentage of the dye (R%). In the drying, the two-term exponential model itted best to the experimental data. he characterization of the material indicated that the adsorbent has zero charge point of 3.5 and porous structure, and the infrared analysis indicated the presence of carboxylic and hydroxyl groups. In the adsorption, the adsorbed quantity of the dye increased under conditions of lower pH and biosorbent mass and higher initial concentration and contact time. he removal percentage of dye increases with higher biosorbent mass. he biosorbent used is a promising waste for the adsorption of the burgundy-16 dye.