Adsorption of Basic green 4 from aqueous solution by olive pomace and commercial activated carbon: process design, isotherm, kinetic and thermodynamic studies

Olive pomace (OP) was used as an adsorbent for the removal of Basic green 4 (BG4) from aqueous solution using adsorption technique. Effects of contact time, adsorbent dose, initial dye concentration, solution pH, and temperature, ionic strength on the adsorption were investigated. Moreover, desorption, isotherm, kinetics, thermodynamics, and process design studies were performed. The adsorption increased with increasing concentration, temperature, and pH, while it was decreasing with the increase in ionic strength. The desorption was highly low in acidic and alkali mediums. Adsorption obeyed the Langmuir, Freundlich, Temkin and Dubinin-Raduskhevich models, and the pseudo-second-order kinetic model. The Langmuir adsorption capacity (Q(o)) was 41.66 mg g(-1). The experimental adsorption capacity of the commercial activated carbon was quite high relatively to the OP. A single-stage batch adsorber design was suitable for the usage of the OP in removing of the BG4. Furthermore, Fourier transform infrared, scanning electron microscopy, and thermodynamic studies were also performed.