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[en] Highlights: • Cathodic reduction becomes a feasible alternative to activate persulfate. • A synergistic effect of electro-PS with heat activation improve the DB3 mineralization. • Complete decolorization within 30 min was achieved at 70 °C in the synergic process. - Abstract: This work assesses the role of the operational conditions upon the electro-activation of persulfate (electro-PS) using Ti/IrO2Ta2O5 electrode for the decolorization of anthraquinone azo dye Disperse Blue 3 (DB3). The studied variables include current density (j) (5–80 mA cm−2), persulfate concentration based on the stoichiometric dose for complete DB3 mineralization (20–100%), temperature (30–90 °C) and pH (3–12) as well as the influence of dissolved oxygen. The persulfate activation from cathodic reduction was confirmed by linear sweep voltammetry (LSV). The increase in j enhanced the PS decomposition and, consequently, decolorization efficiency, because of the greater production of sulfate radicals (SO4• −). Besides, the combination of electro-PS with thermal activation resulted in a synergistic effect upon the DB3 mineralization. In the range 30–70 °C, electro-PS led to a significantly higher TOC conversion (above 60% at 40 mA cm−2) than sole heat-activated PS. This difference steeply decreased as temperature increases, achieving similar TOC conversion at 90 °C after 60 min.
[en] In the last few years, several works dealing with Fenton oxidation of ionic liquids (ILs) have proved the capability of this technology for their degradation, achieving complete ILs removal and non-toxic effluents. Nevertheless, very little is known about the kinetics of this process, crucial for its potential application. In this work, the effect of several operating conditions, including reaction temperature (50–90 °C), catalyst load (10–50 mg L−1 Fe3+), initial IL concentration (100–2000 mg L−1), and hydrogen peroxide dose (10–200% of the stoichiometric amount for the complete IL mineralization) on 1-butyl-3-methylimidazolium chloride ([C4mim]Cl) oxidation has been investigated. Under the optimum operating conditions (T = 90 °C; [Fe3+]0 = 50 mg L−1; [H2O2]0 = 100% of the stoichiometric amount), the complete removal of [C4mim]Cl (1000 mg L−1) was achieved at 1.5-min reaction time. From the experimental results, a potential kinetic model capable to describe the removal of imidazolium-based ILs by Fenton oxidation has been developed. By fitting the proposed model to the experimental data, the orders of the reaction with respect to IL initial concentration, Fe3+ amount and H2O2 dose were found to be close to 1, with an apparent activation energy of 43.3 kJ mol−1. The model resulted in a reasonable fit within the wide range of operating conditions tested in this work.
[en] The Master in Nuclear Engineering and Applications (MINA) was born to build up a bridge between University education and the technical skills demanded by nuclear industry and organizations, particularly in Spain. Motivated by nuclear renaissance, knowledge preservation and the bases of the European Education area, the new approach adopted to accomplish such a challenge has been heavily based on a professional profile defined by the Spanish nuclear community. The first edition success (MINA-2008) has been assessed through a set of indicators, which encompass a broad range of aspects, from the number of registrations to the employment rate. This paper summarizes and discusses such an assessment. Additionally, a critical thorough review has allowed identifying a few aspects that could be improved. All the lessons learned have been translated into specific measures implemented in the MINA-2009 edition. Among the indicators, participation and industrial support were considered of utmost importance. MINA-2008 had 18 students, out of which 60% were financially supported to some extent thanks to the nuclear industry and organizations (during the conduction of the master project, this support was even enhanced). Beyond the economic contribution, nuclear companies and institutions were strongly involved in all the phases of MINA-2008, from the definition of the program up to the supervision of more than 70 % of the master projects. As a result of the lessons learned, the subjects have been grouped in modules and a more practical approach has been pursued in the teaching/learning process. (authors)