3D printed floating photocatalysts for wastewater treatment Articles uri icon

authors

  • MARTIN DE VIDALES, MARIA J.
  • NIETO MARQUEZ, ANTONIO
  • MORCUENDE, DAVID
  • ATANES, EVANGELINA
  • BLAYA HARO, FERNANDO
  • SORIANO HERAS, ENRIQUE
  • FERNANDEZ MARTINEZ, FRANCISCO

publication date

  • May 2019

start page

  • 157

end page

  • 163

volume

  • 328

International Standard Serial Number (ISSN)

  • 0920-5861

abstract

  • Organic contaminants, specifically contaminants of emerging concern (CECs), have a great environmental impact, since the removal of these pollutants is of great difficulty by conventional treatments and the presence of these pollutants in the aquatic medium, even at low concentrations, is extremely hazardous to human health. Advanced oxidation processes and, specifically, TiO2-photocatalytic process is considered an option with positive results for an efficient treatment. However, the photocatalyst must be accessible to the UV radiation, for the activation of the TiO2. For this reason, it is recommendable to use a floating photocatalyst (with lower density than water) if the UV light comes from the solar radiation, because it will be on the water surface. In addition, this characteristic of the catalyst can entail an increase of the process efficiency if the pollutant is mainly located on the surface of water. In this context, the goal of this work is the preparation of floating photocatalysts for the removal of CECs from wastewater. TiO2 is deposited in low-density-polyethylene (LDPE), support with lower density than water and high stability and resistance to degradation. LDPE-TiO2 mixtures were prepared by different methods: mixing TiO2 and LDPE in a hot-cylinder-mixer or using o-xylene or an anionic surfactant as dispersing agent, in order to increase the dispersion of TiO2 before extrusion. Filaments obtained were printed as meshes in a Fused-Deposition-Modelling 3D-printer. The printed photocatalysts improved the activity in comparison with the plate obtained in the cylinder, used as benchmark. Thus, this study opens the doors to the in-situ treatment of CECs, using floating photocatalysts and solar radiation as the sole reagent, a very economical, efficient, easily implantable and environmentally compatible process.

keywords

  • fused deposition modelling; photocatalysis; polyethylene mesh; wastewater treatment; 3d printing; advanced oxidation technologies; emerging concern; methylene-blue; removal; contaminants; degradation; pharmaceuticals; effluents; tio2