LAUSR

Wastewater containing high concentration of ammonium-nitrogen ( NH4+‐N) is not effectively addressed by biological treatment and when released into water bodies can cause eutrophication. In this study, the removal of NH4+‐N from simulated wastewater using chitosan-coated bentonite (CCB) was investigated. The effects of NH4+ salt used, pH, CCB dosage, agitation rate, and temperature on the removal of NH4+‐N were studied. The highest NH4+‐N removal of 67.5% was attained at the following conditions: initial pH 4.0, CCB dose of 8.0 g, agitation rate of 150 rpm, and temperature of 35 °C. Fourier transform infrared analysis indicated two mechanisms: NH4+‐N adsorption onto CCB involving hydrogen bonding with hydroxyl groups (OH) and ion exchange between NH4+‐N and cations present in the interlayer of bentonite. Experimental data follows the pseudo-second-order kinetic model (R2 = 0.9964) and Koble–Corrigan isotherm (R2 = 0.9705). Thermodynamic studies showed that the adsorption process is spontaneous (ΔG0  0) in nature, and leads to an increase in randomness at the solid–solution interface (ΔS0 > 0). © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 135, 45924.