Adsorption of bisphenol a from aqueous solutions by activated tyre pyrolysis char-effect of physical and chemical activation

Abstract

This paper aims to show the effect of activation method of tyre pyrolysis char (TPC) on adsorption of bisphenol A (BPA) from aqueous solutions. The TPC was produced from end-of-life-tyres (ELT) feedstock in a pilot plant at 773 K. Activation was accomplished using two classical methods: Physical activation withCO2 and chemical activation withKOH. The two produced adsorbents had pores ranging from micro-to macropores. Distinct differences in the BET surface areas and pore volumes between the adsorbents were displayed showing better performance of the chemically activated adsorbent for adsorption of BPA from water. The results of the kinetic studies showed that the adsorption of BPA followed pseudo-second-order kinetic model. The Freundlich, Langmuir, Langmuir-Freundlich and Redlich-Peterson isotherm equa-tions were used for description of the adsorption data. The Langmuir-Freundlich isotherm model best fits the experimental data for the BPA adsorption on both adsorbents. The Langmuir-Freundlich monolayer adsorption capacity, qmLF, obtained for the CO2-activated tyre pyrolysis char (AP-CO2) and KOH-activated tyre pyrolysis char (AP-KOH) were 0.473 and 0.969 mmol g1, respectively.