Open AccessPorous Silica Microspheres with Immobilized Titania Nanoparticles for In‐Flow Solar‐Driven Purification of Wastewater
Author(s) -
Marques Ana C.,
Vale Mário,
Vicente Daniel,
Schreck Murielle,
Tervoort Elena,
Niederberger Markus
Publication year - 2021
Publication title -
global challenges
Language(s) - English
Resource type - Journals
ISSN - 2056-6646
DOI - 10.1002/gch2.202000116
Subject(s) - photocatalysis , methyl orange , materials science , anatase , porosity , chemical engineering , microsphere , wastewater , nanoparticle , specific surface area , nanotechnology , raw material , waste management , catalysis , composite material , chemistry , organic chemistry , engineering
In this paper, inorganic silica microspheres with interconnected macroporosity are tested as a platform for designing robust and efficient photocatalytic systems for a continuous flow reactor, enabling a low cost and straightforward purification of wastewater through solar‐driven photocatalysis. The photocatalytically active microspheres are prepared by wet impregnation of porous silica scaffolds with Trizma‐functionalized anatase titania (TiO 2 ) nanoparticles (NPs). NPs loading of 22 wt% is obtained in the form of a thin and well‐attached layer, covering the external surface of the microspheres as well as the internal surface of the pores. The TiO 2 loading leads to an increase of the specific surface area by 26%, without impacting the typically interconnected macroporosity ( ≈ 60%) of the microspheres, which is essential for an efficient flow of the pollutant solution during the photocatalytic tests. These are carried out in a liquid medium for the decomposition of methyl orange and paracetamol. In addition to photocatalytic activity under continuous flow, the microspheres offer the advantage that they can be easily removed from the reaction medium, which is an appealing aspect for industrial applications. In this work, the typical issues of TiO 2 NPs photocatalysts are circumvented, without the need for elaborate chemistries, and for low availability and expensive raw materials.