Simple and effective one-step production of high-quality mesoporous pyrolytic char from waste tires: Rhodamine B adsorption kinetics and density functional theory (DFT) study

Abstract

Pyrolytic tire (PT) chars were first produced from waste car tires (WCT) through carbonization process at 800 °C, for different retention times. Then, best PT-char sample by its physicochemical properties (WCT 800(1 h)) was further tested for its ability to adsorb Rhodamine B (RhB) dye from aqueous solutions. Structural characterization of synthesized material showed existence of graphene-based material, with average pore diameter of 22.8 nm and specific surface area of 55.8 m2·g−1. Obtained carbon material meets specifications of commercial carbon black (CB). The yield of 33.6% of CB recovered has been achieved. Under the optimal conditions, 99.57% of RhB was removed. Adsorption of RhB obeys pseudo second-order model and Langmuir isotherm model. DFT (the density functional theory) was revealed that effective bonding of RhB onto WCT 800 originates from π-electron interactions with aromatic moieties and chemical (or at least the electrostatic) interactions, between positive nitrogen and electron-rich surface groups.