Mechanisms and Models of Adsorption: TiO2-Supported Biochar for Removal of 3,4-Dimethylaniline

Here, 3,4-dimethylaniline (3,4-DMA) was selected as a representative organic substance of aniline compounds. A biochar-titanium dioxide (BC-TiO2) composite was prepared by the sol-gel method to investigate its adsorption ability toward the 3,4-DMA compound. Simultaneously, the prepared composite's adsorption ability and physical and physicochemical properties were also investigated. The isotherm studies confirmed that the adsorption of 3,4-DMA on both BC and BC-TiO2 composite agrees with the Langmuir and Toth adsorption models, which means the formation of a monolayer of 3,4-DMA on the surface. The maximum adsorption capacity of 3,4-DMA was 322.58 mg g(-1) and 285.71 mg g(-1) for BC and BC-TiO2, respectively. Furthermore, the adsorption kinetics reveals that the adsorption process of 3,4-DMA on BC and the BC-TiO2 composite is controlled by the pseudo-second-order kinetic model with an R-2 of 0.99.