Treatment of pharmaceutical wastewater containing antibiotic with oxidation processes by metallic catalysts

Pharmaceuticals have turned in to a major class of contaminants due to their widespread usage and known biological effects. Rifampin is known as an antibiotic with a strong red color. It is used in the treatment of many infectious, especially tuberculosis. If it is used in subtherapeutic concentrations, it can lead to drug resistance in the microbial population. Thus, it is essential to remove its low concentrations from the wastewater to inhibit resistance in a pathogenic microorganism and save its effectiveness against tuberculosis. In the present research, the “Oxidation process by metallic catalysts” method, which consisted of zinc and copper, was employed for the first time in order to remove Rifampin from pharmaceutical wastewater. Variables including the total amount of zinc and copper catalysts, the ratio of the catalysts, duration of the reaction, rotation rate, temperature, and the pH considered and evaluated. It revealed that 0.154 mL of the total amount of the mixture of zinc and copper at the ratio of 70:30 in 100 ml of 40-ppm Rifampin solution, in the neutral pH and at ambient temperature (around 25ºc) and rotation rate, could decrease the concentration of Rifampin to 1 ppm after 120 minutes. The catalysts could be used many times in order to remove the Rifampin from fresh wastewater. It was also shown that 96.4% of Rifampin could be removed from handmade Rifampin solutions and actual wastewater with 70% zinc and 30% copper in 600 rpm, the neutral pH, and the ambient temperature for 120 minutes. The catalysts could be used repeatedly to remove the Rifampin from fresh wastewater.