Sequestration of Paracetamol from Aqueous Solution Using Zinc Oxide/Polypyrrole Nanocomposite: Cost Analysis, Scale-Up Design, and Optimization of Process Parameters
Bibek Saha, Saptarshi Gayen, Animesh Debnath
Abstract
The production of pharmaceuticals in recent years has been racing to its peak due to the advancement of society that has led to a rise in a variety of diseases. Thus, disposal of these untreated pharmaceutical products coming from hospital wastewater and medicine manufacturing plants to the water system is causing a serious environmental threat. Therefore, this work mainly focuses on the removal of one of the widely used pharmaceuticals (e.g., paracetamol) with the help of adsorption technology from water using a metal oxide-based polymer, that is, zinc oxide/polypyrrole (ZnO/PPy). The fabricated adsorbent was characterized with X-ray diffraction, field emission gun–scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and Brunauer–Emmett–Teller analysis to identify its crystal formation, morphology, effective functional groups, and surface area, respectively. A pseudo-second-order kinetic model better suits this adsorption study compared with the pseudo-first-order and intraparticle diffusion model. Langmuir isotherm model fits better and provided a paracetamol adsorption capacity of 25.51 mg/g for ZnO/PPy. Monovalent anions (e.g., Cl−, NO3−, and HCO3−) have less impact on the removal efficiency of paracetamol (3.0% to ∼10.0%) as compared with divalent anion (e.g., S2−) in this adsorption process. The lab scale synthesis cost of ZnO/PPy was observed as ∼111 USD/kg whereas the cost associated with the removal process of paracetamol was found to be ∼4,347 USD/kg of paracetamol. Batch mode scale-up design indicated that the addition of ∼426 g of ZnO/PPy is required for 50 L of contaminated water treatment with 95% paracetamol removal efficiency.