THE REMOVAL AND TREATMENT OF ACTIVE PHARMACEUTICAL INGREDIENTS FROM WASTEWATER TREATMENT PLANTS

Abstract

Pharmaceutical products constantly released into the environment remain a big problem the society today. Furthermore, the fact that these active pharmaceutical ingredients remain stable in wastewater for extended periods exacerbates the issue. In this research, we focused on the thermal stability of five selected active pharmaceutical ingredients and also investigated their degradation by noncatalytic ozonation. The five active pharmaceutical ingredients initially programmed for this investigation were: Diclofenac (DCF), Sulfadiazine (SDZ), Ibuprofen (IBU), Carbamazepine (CMZ), and Metoprolol (MPL). Thermal stability tests were carried out on these five by placing the 10mg/l concentrations of each in an incubator set at a temperature of 40 degrees Celsius. 1 ml samples were taken from each mixture and analysed using High Performance Liquid Chromatography. During this Analysis, Metoprolol was found to be very unstable when found in a mixture of all 5 at room and oven/incubator temperatures. All the rest of the binary mixtures from these active pharmaceutical ingredients were relatively stable for 28 days. Due to the instability of Metoprolol in a mixture of all 5 at room and oven temperatures, it was replaced by sulfamethoxazole for the next phase. In this next phase, a mixture of all five active pharmaceutical ingredients were non-catalytically ozonated for over a period of one hour. It was discovered that; During this period, 99.5% of carbamazepine, 97.5% of diclofenac, 92.7% of ibuprofen, 74.1% of sulfamethoxazole, and 46.3% of sulfadiazine were either degraded or transformed into their respective byproducts. Sulfadiazine and sulfamethoxazole were still present in high concentrations, while ibuprofen, carbamazepine, and diclofenac were only present in minute concentrations. Despite all these low concentrations left in the solution, it took a longer period for all these small concentrations of the original active pharmaceutical ingredients to be completely degraded or transformed into their respective byproducts