Removal of propranolol in MilliQ water and wastewater by photo-Fenton process including experimental desingn

Abstract

The water pollution has been increasing along time, being this big problem that threats the environment. Emerging contaminants (ECs) such as pharmaceuticals present a peculiar problem because conventional water treatment plants in many cases cannot completely remove them and can cause a large environmental impact. Therefore, it is necessary to use alternative treatments such as advanced oxidation processes (POAs) that are based on the production of reactive species (especially the hydroxyl radical OH·) to degrade or transform chemical pollutants. The aim of this study was to investigate the effect of advanced oxidation processes photo-Fenton on the removal to pharmaceutical pollutant: propranolol hydrochloride (PROP). Has been selected this emerging contaminant β-blocker because it is highly prescribed to treat arterial hypertension, irregular heart rhythm, certain types of tremors and migraine. PROP removal was studied in a reactor with artificial light (black light blue and UVC) by photolysis and photo-Fenton. All experiments were carried out with 50 mg/L of initial PROP in Milli-Q water and real water, at the same pH=2.8 and at different concentrations of reagents iron (II) (Fe2+, 5 ppm and 10 ppm) and ratio Fe+2/H2O2, 0.1 and 0.4. The results show that after 60 minutes of treatment PROP removal was high in all of the experiments (>50%). The UVC reactor shows the best results, however this fact is due to the contribution of photolysis added to the UV/H2O2 process since the regeneration of iron doesn’t occur correctly in the UVC, so the photofenton process isn’t given correctly. It is decided to apply an experimental design and thus from the results will be obtained a simple mathematical model that relates the response to the experimental conditions. Thus it was determined which variables are the most influential in the degradation of PROP. Finally a study was made to see the economic viability of each experimental condition, obtaining the efficiencies of each one of them to be able to compare them