Combination of solar photo-Fenton and adsorption process for removal of the anticancer drug Flutamide and its transformation products from hospital wastewater

Abstract

The anti-cancer drug Flutamide (FLUT) is widely used and is of great environmental concern. The solar photo-Fenton (SPF) process can be an effective treatment for the removal of this type of micropollutant. The use of a single addition of 5 mg L^-1 of Fe²⁺ and 50 mg L^-1 of H₂O₂ achieved 20% primary degradation and only 3.05% mineralization. By using three additions of 5 mg L^-1 Fe²⁺, with an initial H₂O₂ concentration of 150 mg L^-1, 58% primary degradation was achieved, together with 12.07% mineralization. Consequently, thirteen transformation products (TPs) were formed. The SPF process was further combined with adsorption onto avocado seed activated carbon (ASAC) as an environmentally friendly approach for the removal of remained FLUT and the TPs. Doehlert design was used to assess the behavior of 13 TPs by optimizing the contact time and the adsorbent mass load. The optimal conditions for removal of FLUT and the TPs were 14 mg of ASAC and a contact time of 40 min. Remained FLUT and the TPs were totally removed using the adsorption process. The mechanisms of adsorption of FLUT and the TPs were strongly influenced by their polarity and π-π interactions of the TPs onto ASAC.

Keywords: Adsorption; Doehlert design; Hospital wastewater; Solar photo-Fenton; Transformation Products.