Removal of pharmaceutical drugs from binary mixtures by use of ZnO nanoparticles

Among various pharmaceutical compounds, antibiotics, analgesics and antipyretics are the major water contaminants, usually occur in the form of multicomponent mixtures in the aquatic environment. In the present work, competitive adsorption of [ciprofloxacin hydrochloride+ofloxacin hydrochloride] and [diclofenac sodium + paracetamol] from binary solutions, in aqueous medium, using ZnO nanoparticles as adsorbent has been studied. Batch experiments have been conducted for concentration ratios 1:0, 1:0.5, 1:1, 1:2, 1:3, 1:4, 1:5 with a view to study the effect of presence of each drug on the uptake of the other. Experiments have been carried out at the optimum pH obtained from single component adsorption studies of respective drugs. The equilibrium adsorption data have been analysed using Langmuir competitive model. For drug ratios varying from 1:0, 1:0.5, 1:1, 1:2, 1:3, 1:4, 1:5 in each case, it is observed that percentage removal of the primary component shows a decrease. Results thus indicate an antagonistic effect on the adsorption of each drug due to the presence of the second component. (C) 2019 Elsevier B.V. All rights reserved.