Photocatalytic degradation of endocrine disruptors in water using porous inorganic/carbon hybrid materials

AQUINO, GUILLERMO D.; SUN TINGWEI; BENEDICTTO, GERMÁN P.; PEREYRA, ANDREA M.; ANIA CONCHI; BASALDELLA, ELENA I.

Buenos Aires

Congreso; 11th World Congress of Chemical Engineering; 2023

Asociación Argentina de Ingenieros Químicos

The excessive occurrence of endocrine disruptors in the aquatic media has become a great danger to the ecosystems and human health, Parabens are a part of this family of pollutants, frequently used as preservatives in cosmetics, skin creams and food due to their wide spectrum of antimicrobial and antibacterial activity. Their discharge to domestic wastewaters is the main route of entry of these compounds in the environment. Like most of the compounds listed as priority toxic pollutants, they are hardly eliminated by conventional treatments in existing WWTP, ending up in water bodies. Hence, technological solutions are needed to upgrade conventional WWTP for the removal of the compounds. In this sense, photodegradation is an interesting process to degrade recalcitrant pollutants (including parabens) from diverse effluents [1,2]. The limited activity of most semiconductors (including TiO2 benchmark) under visible light has triggered investigations on the use of alternative photocatalysts for this application. Among them, the use of hybrid carbon-inorganic materials has gained interest in this field.In this study, a series of hybrid porous inorganic-carbon materials have been prepared by sol-gel and hydrothermal approaches and used for the photocatalytic degradation of parabens from solution, Various high surface silica-based matrices (microporous zeolite and mesostuctured hexagonal silica) as well as hidrotalcite-derived metallic oxides, have been combined with carbon materials from different origins (e.g., C3N4, activated carbon, graphene oxide) to obtain the porous hybrid heterojunctions. The optical, morphological and structural features of these mixed photocatalysts have been characterized by various techniques (diffuse reflectance, SEM/TEM, XRD, photoelectrochemical techniques), and linked to their photocatalytic activity towards the degradation of parabens from solution. Special emphasis has been paid to the role of the nanoporosity of the mixed matrices and the interactions with the paraben compounds, Systematic studies have been performed to evaluate the photocatalytic degradation pathways through the identification of degradation intermediates and the use of radical scavengers.