Sequestration of p-nitrophenol from liquid phase by poly(acrylonitrile-co-acrylic acid) containing thioamide group

Abstract

In this paper, the adsorptive performance of synthesized thiourea (TU) modified poly(acrylonitrile-co-acrylic acid) (TU-P(AN-co-AA)) polymeric adsorbent capturing p-nitrophenol (PNP) from aqueous solution was investigated. The TU-P(AN-co-AA) was synthesized via the redox polymerization method with acrylonitrile (AN) and acrylic acid (AA) as monomers and modified chemically with thiourea (TU). Characterization analysis with Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), CHNS, zeta potential measurement, Brunauer–Emmett–Teller (BET) surface analysis and thermal analyses were carried out to determine the morphology and physico-chemical properties of synthesized polymer. The characterization results had indicated successful surface modification of polymer with TU. The performance of TU-P(AN-co-AA) in removal of PNP were investigated under various experimental parameters (adsorbent dosage, initial adsorbate concentration, contact time and temperature). The results had demonstrated that the Freundlich isotherm model and pseudo-second-order kinetic model best described the equilibrium and kinetic data, respectively. Thermodynamic studies had showed that the uptake of PNP by TU-P(AN-co-AA) was spontaneous and exothermic in nature. The results from the regeneration studies suggested that the TU-P(AN-co-AA) polymer is a reusable adsorbent with great potential in removing PNP from wastewater.