TiO₂ Decorated Sand Grains for Photodegradation of Pollutants: Methylene Blue and Ciprofloxacin Study

Abstract

This study shows a preparation and evaluation of a new non-expensive TiO₂ based photocatalyst built over sand grains surfaces as an alternative green technology for water treatment. The semiconductor covalently bonded to the silica sand grains (sand@TiO₂) prepared by hydrolysis of isopropoxide orthotitane over sand grains, showed a high surface area 296 m² g^-1 and a high reaction rate for methylene blue (MB) photodegradation (0.064 min^-1), on steady state condition by using 3 g of sand@TiO₂ and an MB solution (20 mL, 3 × 10^-5 mol L^-1) or ciprofloxacin hydrochloride (CIP) solution (20 mL, 1.9 × 10^-3 mol L^-1). Under UV irradiation with a medium pressure Hg lamp, the total MB removal reached 70% after 7 min and 45% for CIP in 60 min. Further, the photocatalyst showed to be a promising reusable material for removal of ciprofloxacin hydrochloride antibiotic (CIP) on wastewater. This new material appears as a new promising low cost and low impact reusable catalyst for water treatment.

Keywords:
TiO₂; methylene blue; ciprofloxacin; photodegradation; reusable catalyst