Degradation of sulfamethoxazole antibiotic in MIL88-A/PS systems: implication of solar irradiation for process improvement.

Abstract

PPCPs, a class of emerging contaminants poses significant negative impacts on the ecosystem and possibly on human health. Sulfamethoxazole (SMX), an antimicrobial agent, has been detected, at trace concentrations, in surface water around the globe. One of the main entry routes of SMX is its discharge from pharmaceutical production plants. AOPs are the established methods for the elimination of high concentration of hazardous organic compounds, in an aqueous matrix, such as SMX. PS-based AOPs have shown, over the last 10 years, to be the most efficient and sustainable alternative to H2O2 based AOPs. PS can be activated by several methods, the simplest is the homogenous chemical activation by ferrous ions. The pursuit for new candidate activating agents that require fewer chemicals and are easily separated from the bulk solution is important for developing PS-based AOPs. Metal Organic Frameworks (MOFs), a relatively new class of porous 3d material, are being researched for their applications in environmental remediation and waste water treatment. MIL-88-A, an iron based MOF (Fe3+/Fumaric acid), is synthesized in aqueous medium, a greener advantage over other MOFs that require organic solvents. The aim of the project is to characterize MIL-88-A and to test its capability to act as an assisting agent for the elimination of PPCPs from waste water using AOPs. A solution containing SMX, was placed in continuously stirred reactors, irradiated with two commercial UVA lamps or solar irradiation and finally spiked with PS and MIL-88-A consecutively. The study shows the combined effects of UVA or solar /MIL88-A/PS as well as the effect of various factors such as MOF load, and matrix effect. It also investigates the activation mechanism, its effectiveness, recyclability of MIL-88-A. R. Total degradation of SMX ([SMX]0 = 5 ppm) occurred in a period of two hours using a system of UVA/MIL-88-A/PS and complete degradation occurred in 5-20 minutes in a system of Solar/MIL-88-A/PS.