Removal of crystal violet dye from wastewater using sludge from treatment plant: equilibrium and kinetics studies.

摘要: The application of modified sludge waste and it's use as efficient and low-cost adsorbents lead to help diminish waste and thus reduce environmental problems. In this study the adsorption capacity of sludge was improved by activating it at 200℃ for 60 minutes and used for the removal of crystal violet (CV) dye from wastewater. The sludge was characterized by XRF, FTIR, SEM and XRD. Experiments were conducted to optimize several parameters such as contact time, pH, adsorbent dosage and initial dye concentration. Batch tests demonstrated that CV adsorption was substantially pH dependent and the optimum pH value for dye adsorption was determined as 5.0. The maximum removal of CV was obtained at pH 5.0 as 96% for adsorbent dose of 0.30 g/20 mL and 10 mg/L initial dye concentration at 30℃. Langmuir, Freundlich, Temkin and Dubinin-radushkevich isotherm models were used to correlate adsorption …