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The present work aims to evaluate the activity of semiconductor oxides (TiO 2 , Nb 2 O 5 and ZnO) supported on NaA and NaY zeolites, as well as their synergistic effect on Reactive Blue Dye (RB250) photodegradation process. Prior to deposition, TiO 2 particles size was reduced by ultrasonic scattering followed by filtration. The particles on the filtrate were used to conduct the experiments. The semiconductors were immobilized in concentrations of 2.5, 5 and 10% (w w -1 ) and the photocatalytic tests were performed at catalyst concentrations of 1 and 2 g L -1 . Moreover, supported catalysts were characterized by XRD, textural analysis, zero point of charge and temperature programmed desorption of NH 3 . A comparison between the supported catalysts showed high activity for the ones supported with ZnO and TiO 2 . Zeolite NaY has broader opened channels than NaA, which reduces the dye molecules blockage, and, as a result, increased the catalyst activity. A higher concentration of supported catalysts (2 g L -1 ) provides greater photocatalytic activity, while higher concentration of semiconductors immobilized on supports does not present significant differences.Efeito sinérgico entre óxidos semicondutores e zeólitas no fotoclareamento do corante têxtil RB250 RESUMO. O objetivo deste trabalho foi avaliar a atividade dos óxidos semicondutores (TiO 2 , Nb 2 O 5 & ZnO) suportados nas zeólitas NaA e NaY e seu efeito sinérgico na fotodegradação do corante têxtil azul reativo (RB250). Antes da deposição, o tamanho das partículas de TiO 2 foi reduzido por dispersão em ultrassom seguido por filtração e foram utilizadas as partículas que passaram através do filtro. Os semicondutores foram imobilizados em concentrações de 2,5, 5 e 10% (m m -1 ) e os testes fotocatalíticos foram realizados em concentrações de catalisador de 1 e 2 g L -1 . Os catalisadores suportados foram caracterizados por DRX, análise textural, ponto de carga zero e dessorção por temperatura programada. Os catalisadores suportados com ZnO e TiO 2 mostraram maior atividade do que o Nb 2 O 5 . Os testes fotocatalíticos indicaram um aumento na atividade dos catalisadores suportados em NaY sendo essa com resultados superiores aos encontrados com a zeólita NaA. Isso por causa dos seus canais mais estreitos que dificultam a entrada de moléculas do corante. A maior concentração de catalisadores suportados (2 g L -1 ) proporciona maior atividade fotocatalítica, enquanto a maior concentração de semicondutores imobilizados em suportes não apresenta diferenças significativas.

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The objective of this work was to evaluate the photocatalytic activity of zinc oxide catalysts supported on natural zeolite clinoptilolite for photocatalytic degradation of the drug hydroxychloroquine, used in the treatment of malaria and which has been tested in the treatment of COVID-19. To synthesize 10%ZnOCP and 15%ZnOCP catalysts, the wet impregnation methodology was used. The raw and synthesized catalysts were characterized by XRD, SEM, XRF, BET, DRS, PCZ, FT-IR and PL. The degradation of hydroxychloroquine was calculated using UV-vis absorption from the samples before and after the photocatalytic process. The maximum percentage of degradation (96%) was obtained with the operational parameters of C0 = 10 mg L−1; Ccat = 2 g L−1 of 15%ZnOCP; pH = 7.5; UV-A radiation. Ecotoxicological tests against the bioindicators Lactuca sativa and Artemia salina confirmed the reduction of effluent toxicity after treatment.

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