A Comparative Study of Acid Red 119 Dye Adsorption onto Dried Sewage Sludge and Sewage Sludge Ash: Isotherm, Kinetic and Desorption Study

摘要

This study presents a comparison between dried sewage sludge (DSS) and sewage sludge ash (SSA) for Acid Red 119 dye removal. Results revealed that optimal pH, contact time and adsorbent dosage for DSS and SSA were (3, 11), (120, 30 min) and (5, 4 g/L), respectively. Isotherm and kinetic studies revealed that both adsorbents follow Freundlich isotherm and second-order kinetic models. The maximum adsorption capacities of DSS and SSA were found 90.91 and 142.88 mg/g, respectively. For SSA, a significant decrease in the decolourization efficiency from 98.87% to 79.31% was observed when a simulated wastewater containing the dye, acetic acid and Glauber’s salt dissolved in tap water was used whereas for DSS, the efficiency was not changed significantly. Additionally, desorption/reuse studies of the dye-loaded adsorbents were found unsuccessful.