ENVIRONMENTAL TECHNOLOGY, cilt.38, ss.424-432, 2017 (SCI İndekslerine Giren Dergi)
In this study, surfactant-modified natural zeolite was used to remove Bisphenol A (BPA) from aqueous solutions. Kinetics, equilibrium and thermodynamics of BPA adsorption on the adsorbent surfaces were investigated. The experimental data were described with the Temkin isotherm and the pseudo-second- order kinetic model. Taguchi's robust design approach was used to optimize adsorption of BPA. Experimentation was planned as per Taguchi's L27 orthogonal array. Tests were conducted with different adsorbate amount, pH, time, initial concentration of BPA, temperature and agitation speed. The optimum levels of control factors for maximum total organic carbon removal were defined (adsorbate amount at 0.25g, pH at 7, time at 30min, initial concentration of BPA at 50mg/L, temperature at 30 degrees C and agitation speed at 200rpm). The ANOVA analysis shown that the most effective control factor is adsorbent dosage; its contribution is 56.4%. Contribution of pH and mixing rate are 7.5% and 7.6%, respectively. A confirmation experiment was conducted to verify the feasibility and effectiveness of the optimal combination. The observed value of S/N ((obs)=39) ratio is compared with that of the predicted value ((opt)=48). The prediction error, that is, (opt)-(obs)=9, is within CI value.