Removal of endocrine disrupting chemicals from aqueous phase using spherical microporous carbon prepared from waste...

A spherical microporous carbon adsorbent (CR-1), which was developed by carbonization and activation of the waste polysulfonated cation-exchanger, was used to remove Dimethyl phthalate (DMP) and 2, 4-dichlorophenol (2, 4-DCP) as the model compounds of EDCs from the aqueous solution. Four adsorption isotherm models, Langmuir, Freundlich, Toth and Polanyi-Dubinin-Manes equations were tested to correlate the experimental data, Toth and Polanyi-Dubinin-Manes isotherms models provided the best correlation. The Henry's law constants calculated from Toth equation were found to be 705.957 and 6,724.713 L g(-1) for 2, 4-DCP and DMP at 298 K, respectively, and the larger exponents n of the Freundlich model were 9.011 and 9.93 for 2, 4-DCP and DMP at 298 K, respectively. The values of Henry's law constants and exponent n of the Freundlich suggested that CR-1 was an effective adsorbent for removal of low concentrations of DMP and 2, 4-DCP from aqueous solution. Moreover, the adsorption kinetics results showed that adsorption of 2, 4-DCP and DMP on CR-1 was a pseudo-second-order process controlled by intra-particle diffusion and that adsorption uptake reached quickly half of equilibrium capacities within 20 min.