Isotherm studies of methylene blue adsorption onto waste tyre pyrolysis powder-based activated carbons

This study was aimed to investigate the adsorptive ability of activated carbons derived from waste tyre pyrolysis powder by CO2 activation and ZnCl2 activation. The derived activated carbons and char were characterized for yield and specific surface area. Methylene Blue dye was used as a model pollutant to probe the performance of activated carbons. Result shows that the CO2-activated waste tyre pyrolysis powder exhibits a higher surface area of 97.0 m2/g, hence a greater methylene blue removal capacity of 47.2 mg/g. The methylene blue adsorption data by activated carbons and char obeyed the Langmuir isotherm with R2 of more than 0.99, describing the monolayer adsorption onto homogeneous surface. Physical activation of waste tyre pyrolysis powder using CO2 yields activated carbon with a promising performance for dyes removal from water.