Abatement of the fluorinated antidepressant fluoxetine (Prozac) and its reaction by-products by electrochemical advanced methods

Abstract

Abatement of the fluorinated antidepressant fluoxetine (Prozac) and its reaction by-products by electrochemical advanced methods, Applied Catalysis B, Environmental http://dx.GRAPHICAL ABSTRACT Fluoxetine hydrochloride (fluorinated antidepressant) 4 primary aromatics 1 chloroaromatic 4 carboxylic acids CO 2 F  NO 3  UVA light BDD(  OH)  OH Research Highlights Fluoxetine hydrochloride treated with Pt, RuO 2 -based or BDD anode and H 2 O 2 generation  Faster mineralization by PEF with a BDD anode due to BDD(  OH),  OH and UVA light  Pseudo-first-order decay by AO-H 2 O 2 , EF and, more rapidly, by PEF using a BDD anode  Degradation of fluoxetine with F  and NO 3  formation and partial Cl  oxidation to HClO  Detection of 4 primary aromatics, 1 chloroaromatic derivative and 4 carboxylic acids AbstractThe degradation of the fluorinated antidepressant fluoxetine, as hydrochloride, was comparatively studied in sulfate medium at pH 3.0 by anodic oxidation with electrogenerated H 2 O 2 (AO-H 2 O 2 ), electro-Fenton (EF) and photoelectro-Fenton (PEF). Experiments were performed with 100 mL solutions in an undivided tank reactor equipped with a Pt, RuO 2 -based or boron-doped diamond (BDD) anode and an air-diffusion cathode for continuous H 2 O 2 production. The BDD anode showed higher mineralization rate due to the great production of physisorbed BDD(  OH), which has larger reactivity to oxidize the drug and intermediates. The degradation rate was enhanced by EF with 0.50 mM Fe 2+ due to the additional production of  OH in the bulk from Fenton's reaction. The degradation was even faster using PEF owing to the additional photolytic action of UVA radiation.The most effective process was PEF with a BDD anode achieving 94% mineralization at 300 min.The fluoxetine decay followed a pseudo-first-order kinetics, being quicker in the order: AO-H 2 O 2 < EF < PEF. The effect of the current density and drug concentration on the mineralization rate and fluoxetine decay was clarified. Oxidation of fluoxetine by hydroxyl radicals yielded four aromatic by-products, as found by GC-MS. Additionally, a chloroaromatic compound was identified as a result of the reaction of active chlorine, which was formed in situ from the oxidation of chloride ion at the BDD anode. Four short-chain linear carboxylic acids, being oxalic and formic acid more abundant, were identified. In PEF, fluorine atoms of fluoxetine were completely released as fluoride ion, whereas the initial nitrogen was converted to nitrate ion in all cases. A reaction pathway for fluoxetine mineralization by the electrochemical advanced methods is finally proposed.

Anodic Oxidation of Chlorinated Pesticides on BDD and PbO2 Electrodes: Kinetics, Influential Factors and Mechanism Determination

“…Chloride and sulphate salts are two of the most used electrolytes for electrochemical treatment. Infact, anodic oxidation of aqueous solutions containing chloride and sulphate anions promotes the formation of hypochlorites and persulphates respectively, and that these chemical species are very powerful oxidant with high standard reduction potentials [16,29].…”

A novel modeling approach for a generalizable photo-Fenton-based degradation of organic compounds

“…As the second model compound, sulfaquinoxaline sodium salt (SQX, C 14 H 11 N 4 NaO 2 S) is selected because it is a potential food contaminant in animal products. Finally, formic acid (FA, CH 2 O 2 ) is studied as the third target compound since it is a by-product of the degradation of many hazardous organic compounds and belongs to the group of carboxylic acids that are hardly degradable even by chemical oxidation (Salazar et al 2017).…”

Photodegradation of Fluoxetine Applying Different Photolytic Reactors: Evaluation of the Process Efficiency and Mechanism

“…3 Due to the observation of the presence of these compounds in different ecosystems and especially their persistence in the environment (difficult degradation), many studies have been carried out to find new alternatives for the treatment of effluents of persistent compounds. [4][5][6][7] Many of these new processes have been applied in the degradation of FLX. [8][9][10][11] It is important to note that the efficiency of degradation of chemical compounds through different processes needs to be verified through some important parameters, such as energy consumption, reagent costs, process time, TPs and, in particular, chemical kinetics.…”