Performance of activated carbons prepared from spent tyres in the adsorption of rhodamine B in aqueous solutions

Activated carbons were produced from spent tyre pyrolysis char by steam or CO2 activation and evaluated for their performance in rhodamine B (RhB) adsorption aqueous solutions. The effect of RhB starting concentration (80–150 mg L−1), contact time (0–80 min), temperature (298–318 K) initial pH on the process was examined. Pseudo-first-order pseudo-second-order models carried out to fit experimental data derive kinetics. Langmuir, Freundlich Temkin isotherm applied depict behaviour prepared activated carbons. Gibbs free energy (ΔG), enthalpy (ΔH) entropy (ΔS) calculated. It has been found that can effectively adsorb due high mesoporosity equilibrium capacity (qe) increased almost linearly with increasing total mesopore volumes, regardless agents. When BET surface areas are similar, CO2-activated carbon obtained higher qe than carbon. results show well fitted data. 80 150 L−1 causing 158 251 g−1 but removal decreased 99.7 84.5%. follows Langmuir model thermodynamic calculation, indicating is an endothermic, spontaneous process, dominated both chemisorption physisorption.