Effect of the preparation method and metal content on the synthesis of metal modified titanium oxide used for the removal of salicylic acid under UV light

• Published in: Environmental technology 2020-07, Vol.41 (16), p.2073-2084
• Main Authors: Santamaría, L., Vicente, M.A., Korili, S.A., Gil, A.
• Format: Article
• Language: English
• Subjects: Acids; Ammonia; Aqueous solutions; Catalysis; Catalysts; Chemisorption; Degradation; Doped titanium oxide; Iron; Irradiation; Light; Organic chemistry; Photocatalysis; Photodegradation; Photoelectron spectroscopy; Photoelectrons; Salicylic Acid; salicylic acid removal; Silver; sol-gel method; Sol-gel processes; Titanium; Titanium dioxide; Titanium oxide; Titanium oxides; Ultraviolet radiation; Ultraviolet Rays; wet impregnation method; X ray photoelectron spectroscopy; X ray powder diffraction; X-Ray Diffraction
• ISSN: 0959-3330; 1479-487X
• DOI: 10.1080/09593330.2018.1555285

Titanium dioxide modified with Ag and Fe was synthesized using two preparation methods, characterized and applied to the photocatalytic degradation of salicylic acid in aqueous solution. The modified TiO 2 samples were prepared by the sol-gel and wet impregnation methods starting from titanium(IV) isopropoxide and using AgNO 3 and Fe(NO 3 ) 3 ·9H 2 O as precursors of the modifiers, with their content varying between 0 and 5 wt.%. Catalysts characterization was based on powder X-ray diffraction (PXRD), nitrogen physisorption at 77 K, temperature programmed reduction (H 2 -TPR), chemisorption of NH 3 at 343 K and X-ray photoelectron spectroscopy (XPS). The photocatalytic degradation of salicylic acid by modified TiO 2 was investigated under ultraviolet irradiation at 298 K considering various concentrations of the catalyst, between 100 and 1000 mg catalyst /dm 3 , and of the organic molecule, between 0 and 15 mg/dm 3 . The catalysts most active in the degradation of salicylic acid were those having the highest Fe content.