Bisphenol S adsorption with activated carbon prepared from corncob: optimization using response surface methodology

Activated carbon derived from raw corncob (CCAC), which prepared with steam as the activating agent, was used to adsorb bisphenol S (BPS) from aqueous solution. Characterizations of CCAC were measured by using the Brunauer-Emmett-Teller, scanning electron microscopy, and Fourier transform infrared spectroscopy. Adsorption conditions including initial BPS concentration, contact time, adsorbent dosage and pH were optimized by response surface methodology (RSM). The results show that adsorption equilibrium was well described by the Langmuir and Koble-Corrigan models. The maximum monolayer adsorption capacity of BPS was found to be 617.29 mg g(-1) at 298 K. Based on the thermodynamic parameters analysis, the BPS adsorption process was turned out to be spontaneous and exothermic. The adsorption process of BPS was well described by the pseudo-second-order kinetic model. It also found that H-bonding, pi-pi interaction, and electrostatic interaction were the main mechanisms in the process of BPS adsorption onto the CCAC.