Abstract

The electrochemical oxidation (EO) of hydrochlorothiazide (HCTZ) in water has been carried out at applying constant current in an electrochemical cell containing a boron-doped diamond (BDD) anode and a stainless steel cathode. The effect of initial pH of the solution and the applied current density were evaluated in the HCTZ concentration decay and total organic carbon abatement during the electrolysis. A qualitative analysis of the degradation by-products was made by chromatography and photometric assays. Finally, EO was applied for the HCTZ degradation from commercial formulations. Thus, HCTZ can be degraded by EO at neutral pH, applying low current densities due to the attack of OH electro-generated on the BDD surface. Aromatic intermediates, aliphatic carboxylic acids, and inorganic anions were detected as main products during the mineralization of HCTZ to CO2. Solutions prepared from commercial formulations of HCTZ were completely mineralized by EO, which can be an interesting step towards the applicability of the EO processes for the treatment of wastewater containing these kinds of drugs as raw materials or pharmaceutical formulations.