Preparation and Characterization of Polyvinyl Alcohol/Activated Carbon (PVA/AC) Composite and Its Use in the Adsorption of 4-Nitrophenol (4-NP)

Abstract

In this study, polyvinyl alcohol-activated carbon (PVA/AC) composite was synthesized and characterized by SEM, FTIR, DLS and TGA-DSC measurement. The zero point charge for the PVA/AC was determined as approximately 3 pH. The efficiency of PVA/AC as a cheap adsorbent for removal of 4-nitrophenol (4-NP) from aqueous solution was researched at 298, 318 and 328 K. For this purpose, Freundlich and Langmuir isotherm models were used. According to the results, adsorption of 4-NP onto composite best fitted to Freundlich model. The pseudo-first-order, pseudo-second-order and intraparticle diffusion models were utilized to study the adsorption kinetics. The experimental consequences fitted with the pseudo-first-order model. According to Arrhenius equation, Ea was calculated as 14.13 kJmol-1. Thermodynamic parameters were also calculated, which revealed that the adsorption process is endothermic, not spontaneous.