Photocatalytic reusable membranes for the effective degradation of tartrazine with a solar photoreactor

Recalcitrant dyes present in effluents constitute a major environmental concern due to their hazardous properties that may cause deleterious effects on aquatic organisms. Tartrazine is a widely-used dye, and it is known to be resistant to biological and chemical degradation processes and by its carcinogenic and mutagenic nature. This study presents the use of TiO2 (P25) nanoparticles immobilized into a poly(vinylidenefluoridetrifluoroethylene) (P(VDFTrFE)) membrane to assess the photocatalytic degradation of this dye in a solar photoreactor. The nanocomposite morphological properties were analyzed, confirming an interconnected porous microstructure and the homogeneous distribution of the TiO2 nanoparticles within the membrane pores. It is shown that the nanocomposite with 8 wt% TiO2 exhibits a remarkable sunlight photocatalytic activity over five hours, with 78% of the pollutant being degraded. It was also demonstrated that the degradation follows pseudo-first-order kinetics model at low initial tartrazine concentration. Finally, the effective reusability of the produced nanocomposite was also assessed.This work was supported by the Solar Equipment Development Unit (UDES) Algeria. This work was also supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the strategic project UID/FIS/04650/2013 by FEDER funds through the COMPETE 2020-Programa Operacional Competitividade e Internacionalização (POCI) with the reference project POCI-01-0145-FEDER-006941, and project PTDC/CTMENE/5387/2014. P.M. Martins thanks the FCT for the grant SFRH/ BD/ 98616/ 2013.The authors acknowledge funding from the Basque Government Industry Department under the ELKARTEK Program and the Spanish Ministry of Economy and Competitiveness (MINECO) through the project MAT2016-76039-C4-3-R (AEI/FEDER, UE) (including the FEDER financial support).