The Adsorption of Ammonium Nitrogen from Milking Parlor Wastewater Using Pomegranate Peel Powder for Sustainable Water, Resources, and Waste Management

Abstract

Agricultural wastewater poses serious risks to the environment due to how it is injudiciously used and managed. We investigated the use of pomegranate peel powder (PPP) to adsorb ammonium ions from milking parlor wastewater, which is applied as a nitrogen source for cropland fertilization despite its environmental ramifications. As a valueless by-product of juice and jam industries, PPP shows promising features and characteristics as a potential bio-adsorbent for ammonium nitrogen removal and recovery. The surface characterization of PPP was performed by zeta potential measurement and attenuated total reflectance Fourier transform infrared Spectroscopy (ATR-FTIR) analysis. The adsorption studies were carried out by batch experiments where the initial ammonium nitrogen (NH4–N) concentration of studied wastewater was 80 mg/L. The effects of different operational parameters, such as pH, adsorbent dose, contact time, stirring speed, and temperature, were investigated. From kinetic studies, the equilibrium time was found to be 120 min, achieving an 81.8% removal synonym of ~2.5 mg/g NH4–N uptake. The adsorption isotherm data fitted well with Langmuir model with correlation (R2) > 0.99. Meanwhile, the kinetics followed pseudo-second order model with correlation (R2) > 0.99.