1 Improving the biodegradability of hospital urines 1 polluted with chloramphenicol by the application 2 of electrochemical oxidation 3 Miguel Herraiz-Carboné 1 , Salvador Cotillas 1 , Engracia Lacasa 1 , Ángela Moratalla 2 , 4 Pablo Cañizares 2 , Manuel A. Rodrigo 2 , Cristina Sáez 2* 5 1 Department of Chemical Engineering, School of Industrial Engineering, University of 6 Castilla-La Mancha, 02071 Albacete, Spain 7 2 Department of Chemical Engineering, Faculty of Chemical Sciences and 8 Technologies, University of Castilla-La Mancha, 13005 Ciudad Real, Spain 9 10 Abstract 11 This work focuses on improving the biodegradability of hospital urines polluted with 12 antibiotics by electrochemical advanced oxidation processes (EAOPs). To do this, 13 chloramphenicol (CAP) has been used as a model compound and the influence of anodic 14 material (Boron Doped Diamond (BDD) and Mixed Metal Oxide (MMO)) and current 15 density (1.25 - 5 mA cm -2 ) on the toxicity and the biodegradability was evaluated. Results 16 show that a complete CAP removal was attained using BDD anodes, being the process 17 more efficient at the lowest current density tested (1.25 mA cm -2 ). Conversely, after 18 passing 4 Ah dm -3 , only 35 % of CAP removal is reached using MMO anodes, regardless 19 of the current density applied. Furthermore, a kinetic study demonstrated that there is a 20 clear competitive oxidation between the target antibiotic and the organic compounds 21 naturally contained in urine, regardless the current density and the anode material used. 22