[en] In this PhD Thesis we have studied the advanced oxida!ion processes (AOPs) for the reduction I elimination of fungicides in aqueous medium. These processes have emerged as an alternative to conventional water treatment processes that, in many cases, are not efficient toward the elimination of emerging organic pollutants (EOPs), that are detected in increasing number as a consequence of improvements in the sensibility of analytical techniques. More specifically, we have studied the direct and photocatalyzed transformation of three post-harvest fungicides: Thiabendazole (TBZ), Imazalil (IMZ), and ortoPhenyl Phenol (OPP), commonly applied as a coctel to citric fruits. Generally, Ihese fungicides are eliminated by washing, and the generated residues go directly to residual waters. First, we carried out an in-depth review of the different AOPs that are currently being applied for the degradation of fungicides (benzimidazoles, imidazoles and phenol derivatives), the different families to which the COEs dealt with in this Thesis belong, as we received an invitation to write up a review ar!icle on this topic. Based on the data obtained, direct phototransforrnation with irradiation UV-B (254 nm) for IMZ, TBZ and OPP showed a low efliciency for the elimination of these fungicides, since though their presence is reduced with (72 % TBZ in 300 min, 72 % IMZ in 180 min, 83 % OPP in 180 min), just a par! of them is mineralized (3.7 % TBZ, 0.7 % IMZ and 2.3 % OPP). The lifetimes for phototransforrnation ofTBZ, IMZ and OPP were 221; 22.4 Y 2.6 min, respectively. Moreover, it is observed that for this process in the case of TBZ and fungicides IMZ, the presence of 02 in the reaction media does not alfect the direct phototransformation of TBZ and IMZ, which suggests that only their excited singlet state is involved in the phototransforrnation of both fungicides. On the contrary, 02 showed a clear influence in the case of OPP, which is suppor!ed by both the obtained kinetic results and the observed photoproducts. A peroxide was found as a product, which implies the involvement of excited triplet state of 02; consequently both excited singlet and triplet states of 02 play a role in the phototransformation of oPP. Based on detailed kinetic studies, as well as on the identification of the corresponding photoproducts by HPLC-DAD and HPLC-MS, we propose a phototransformation mechanism for each ofthe studied fungicides, that can serve as a basis to control the process. Photocatalysis showed to be an efficient process for the elimination of OPP, wHh 40% mineralizaton in 180 mino However, the results obtained for the other two fungicides show a negligible photodegradation in the studied conditions. The lifetimes for direct self-transformation by UV-A irradiation (365 nm) IMZ and OPP were 30 and 330 min, respectively, although, for photocatalyzed transformationin the same irradiation conditions - IMZ and OPP were 11.5 and 96.3 min, respectively. Finally, we carried out a study of the photocatalytic activity for different nanostructured photocatalysts, with exhaustive control of different variables influencing this kind of processes: type and concentration of catalyst in suspension and in films, concentration of oxygen in the medium, initial concentration of OPP and radiant flux. As a reference catalyst, we used a commercial form of titanium dioxide, Degussa (Evonik) P25, composed of 78:14:8 anatase, rutile and amorphous phase.

[gl] Nesta Tese Doutoral estudaronse os procesos de oxidación avanzada (AOPs) para a redución I eliminación de funxicidas en disolución acuosa. Ditos procesos xmdiron como alternativa aos procesos convencionais de tratamento de augas que, en moitas ocasións, non son eficientes para a eliminación de contaminantes ofgánicos emerxentes (eOEs), que se detectan en cada vez maior número como consecuencia da mellara da sensibilidade das técnicas analíticas. En concreto estudouse a fototransformación directa e fotocatalizada de tres funxicidas postcolleita: nabendazol (TBZ), Imazalil (IMZ), e orto-Fenilfenol (OPP), comúnmente aplicados aos cítricos coma un cóctel. Polo xeral, estes flmxicídas son eliminados por lavado, e os residuos xerados van directamente ás augas residuais. En pl'imeiro lugar, levóuse a cabo unha revisión en profundidade sobre os AOPs aplicados para a degradación dos funxicidas bencimidazoles, imidazoles e derivados fenólicos, familias ás que pertencen os COEs tratados nesta tese, xa que se recebiu unha invitación para realizar un artigo de revisión sobre este tema. A partires dos datos obtidos, a fototransformación directa con irradiación UV-B (254 nm) de IMZ, de TBZ y de OPP amosou ser un tratamento pouco eficaz para a eliminación destes funxicidas, xa que, a pesares de que se reduce a presenza dos diferentes funxicidas (72 % TBZ en 300 min, 72 % IMZ en 180 min, 83 % OPP en 180 min), só unha parte dos mesmos é mineralizada (3,7 % TBZ, 0,7 % IMZ y 2,3 % OPP). Os tempos de vida media de fototransformación da TBZ, IMZ e OPP foron 221; 22,4 e 2,6 min, respectivamente. Ademais, observouse que na fototransformación directa dos funxicidas TBZ e IMZ a concentración de O, presente no medio non inflúe no proceso, o que indica que solo está involucrado o estado excitado singulete de estes dos funxicidas. 'Pala contra, para o funxicida OPP o 02 amosou un ha clara participación, o que se compraba tanto polos resuHados cinéticos observados en presenza e ausencia de 02 como pala identificación dun peróxido que é un fotoproduto típico de procesos que involucran o estado excitado triplete do O,. Dedúcese que na fototransformación do OPP está involucrado tanto o seu estado excitado singulete coma o triplete. A partires dos estudos cinéticos desenvueltos, así como da identificación dos fotoproductos por HPLC-DAD e HPLC-MS, proponse un mecanismo de fototransformación para cada un dos funxicidas estudados, que sirva de base para facilitar o control do proceso. Para OPP, a fotocatálise amosou ser un tratamento eficaz para a súa eliminación, cunha mineralización do 40 % en 180 mino Sen embargo, nos resultados obtidos para os outros dous funxicidas evidénciase que nas condicións estudadas non se produce unha fotodegradación considerable. Os tempos de vida media de fototransformación directa por irradiación UV-A (365 nm) e OPP IMZ foron 30 e 330 minutos, respectivamente, aínda que, para a fototransformación catalizada - irradiando baixo as mesmas condicións _ de IMZ e OPP foi 11,5 e 96,3 min, respectivamente. Por úHimo, levo use a cabo un estudo da actividade fotocatalitica para diferentes catalizadores nanoestructurados, cun control exhaustivo de diferentes variables que interveñen neste tipo de procesos: o tipo e concentración de catalizador en suspensión e en ti/ms, a concentración de oxíxeno no medio, a concentración inicial de OPP e o f1uxo radiante. Como catalizador de referencia utilizo use unha forma comercial de dióxido de titanio Degussa (Evonik) P25, composta por 78:14:8 de anatasa, rutilo e fase amorfa.