Adsorption of 17β-estradiol and estrone by activated carbon derived from sewage sludge

Nowadays, the number of treatment plants has been increasing due to advancing technology and industrialization throughout Turkey and the world. This situation brings with it the need to analyse the features of the wastewater of treatment plants and treatment sludge in a more detailed way. In recent years, it has been remarkable to see studies conducted on endocrine disrupting substances (EDCs) in wastewaters and treatment sludge and the effects of these substances on the environment and public health. Being one of the estrogenic hormones, which are EDCs and which are found naturally in organisms, 17-estradiol and estrone are highly important for the ecological balance. In the adsorption studies for the removal of estrogenic hormones, removal efficiencies, adsorption isotherms, kinetic values and thermodynamic studies have been conducted for 17-estradiol and estrone. In adsorption studies, isotherm calculations are made with 90% and over removal efficiency and it is seen that the adsorption is in conformity with the Freundlich isotherm. Following the kinetic calculations, it is also seen that the adsorption is in conformity with the second-order rate equations. Following the analysis of the adsorption thermodynamically, G Gibbs free energy is found to be positive and enthalpy and entropy variations are also found to be positive.