Application of electrocoagulation process for the removal of chloroquine from an aqueous solution

Abstract

Using chloroquine (CQ) as a provisional treatment for COVID-19 patients generates more pharmaceutical waste, posing a potential environmental threat. The present study evaluates the feasibility of the electrocoagulation (EC) process in removing CQ from an aqueous solution. The experiment was performed in a laboratory-scale stirred tank reactor (STR). The effects of operating conditions were investigated. Equilibrium and kinetic experiments were also performed to describe CQ adsorption. The results showed that increasing both the applied current density and the EC reaction time increases the removal efficiency of CQ. The results showed that 95% of CQ removal efficiency was achieved at a current density of 66.89 mA/cm2, 600 rpm of agitation rate, 60 min of electrolysis time, an initial CQ concentration of 3 mg/L, and a pH of 6.5. For equilibrium and kinetic studies, the Langmuir isotherm and the pseudo-second-order provided the best fit to the experimental data. The optimal operating conditions led to a specific amount of dissolved aluminum electrodes and a specific energy consumption of 0.228 kg/m3 and 12.243 kWh/m3. These results suggest that the EC process is an excellent tool for effectively degrading CQ from wastewater with a low operating cost (2.48 USD/m3). HIGHLIGHTS Several studies have proven that chloroquine is suitable for treating an infection with SARS-CoV-2.; Huge consumption of chloroquine drugs generates large amounts of pharmaceutical wastewater.; Operating conditions of the electrocoagulation process were discussed.; The Langmuir isotherm and the pseudo-second-order provided the best fit for the experimental data.; The energy consumption and operating costs were calculated.;

Keywords

• chloroquine
• covid-19
• electrocoagulation
• pharmaceutical waste