Orange peels were found to be a suitable material for the preparation of activated carbon by H3PO4 acid activation,showing potentialities for basic dyes removal. The developed activated carbon showed high adsorption capacity for both MB and RhB.
Fast adsorption kinetics of both dyes was successfully described by apseudo-second-order rate model.Low dependency of dyes adsorption on solution pH,which is a very desirable feature in real wastewater treatment,suggests an adsorption mechanism mainly related to the textural properties and dispersion interactions of the orange peel-based carbon. Single and binary isotherms were represented by several models,with the single-component
Langmuir–Freundlich model being themostsatis factory one. Tailed-shaped breakthrough curves from single and binary dye solutions were successfully fitted by a modified two-parameter model. The batch and dynamic experiments using binary dyes solutions allowed the identification of a reduced adsorption of both dyes, pointing to a certain degree of competition for the active sites in the mesopores of the developed carbon.