Study on cationic dye adsorption of bio-chars prepared from thermal-alkaline-pretreated sludge

摘要

Sludge bio-char (SC) and thermal-alkaline treated sludge bio-char (TSC) were prepared from municipal sewage sludge (RS) and thermal-alkaline treated sludge sediments (STAS) through fast pyrolysis under nitrogen existence condition to remove cationic red X-GRL (A) and cationic yelow X-6G (B) from aqueous solutions. Results of adsorption experiment show that the adsorption capacities of TSC are better than the adsorption capacities of SC. The highest adsorption capacity of 47.65 mg/g for A and 45.41 mg/g for B are obtained by TSC in an isotherm experiment at 2.0 g/L dosage and 25 °C temperature.TSC adsorption for the two kinds of cationic dyes can be wel fitted by pseudo-second-order kinetics model and Langmuir isotherm model.