Degradation of Pharmaceuticals from Simulated and Real Hospital Wastewater Using the Conventional Fenton Process: Optimization Conditions and Application

Abstract

This study investigated the treatment of simulated and real hospital wastewater spiked with amoxicillin (AMX), ceftriaxone (CTX), and/or Telebrix (TLX) using the Fenton process. First, the optimal treatment conditions were determined on simulated wastewater by varying the initial concentration of AMX, the H₂O₂/Fe²⁺ ratio (k), and the initial pH. Subsequently, the effects of inorganic ions (Cl⁻, NO₃⁻, SO₄²⁻ and PO₄³⁻), considered both individually and in combination, as well as temperature and the different pharmaceutical compounds, were evaluated under the established optimal conditions. Finally, experiments were performed on real hospital wastewater. Chemical oxygen demand (COD) and spectrophotometric analysis (used to monitor AMX concentration) were employed to assess treatment performance. The results showed that the optimal conditions for the Fenton process were:
0.5 mM AMX, k = 2, and pH 3. The process does not degrade all pharmaceutical compounds with the same efficiency, and its performance decreases at high temperatures and in the presence of inorganic ions. Moreover, the Fenton process exhibited limited efficiency (37.05% COD removal) when applied to real hospital wastewater due to its high inorganic ion content. However, the successive addition of Fenton’s reagent significantly improved COD removal, reaching 88.96% in real wastewater.