Chemical Activation of Sludge from Drinking Water Treatment Plant for Adsorption of Methylene Blue Dye

Abstract

The objective of this study is to explore the preparation and application of sludge produced in plants of drinking water treatment, to remove methylene blue (MB) dye from polluted water. Adsorbate (methylene blue) is prepared in the lab. as a stock solution. To create new adsorbents, chemical activation of the used sludge has been carried out. The activation is performed by HCl and H2O2 and a mixture of HCl and H2O2. The experiments were carried out under different boundary conditions, like the initial concentration of dye, dosage of adsorbent, solution pH, contact time, and temperature of the adsorption, to determine the optimum boundary conditions for operation. All of the experiments in this study were carried out in a batch system. The results show that sludge activation by a mixture of 2:1 HCl/ H2O2 was selected as the best chemically activated adsorbent (removal of 99.9%). For the best MB adsorption results, the following criteria must be met: 50 ppm initial dye concentration, 90 min of contact time, pH 7, and a dosage of 0.25 g of the adsorbent. Adsorbents suit the Langmuir and Freundlich models well, according to applications of the Freundlich Isotherm and Langmuir models.