A study on deactivation and regeneration of titanium dioxide during photocatalytic degradation of phthalic acid

• Published in: Journal of industrial and engineering chemistry (Seoul, Korea) Vol. 18; no. 6; pp. 1902 - 1907
• Main Authors: Gandhi, Vimal G., Mishra, Manish Kumar, Joshi, Pradyuman A.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 25.11.2012; 한국공업화학회
• Subjects: Catalysts; Deactivation; Degradation; Hydrogen peroxide; Photocatalysis; Regeneration; Regeneration and reuse; Solvents; Surface chemistry; Titanium dioxide; 화학공학; Regeneration and reuse; Deactivation; Hydrogen peroxide; Titanium dioxide
• ISSN: 1226-086X; 1876-794X
• DOI: 10.1016/j.jiec.2012.05.001

The cause of deactivation of TiO2 catalyst during photocatalytic degradation of phthalic acid in aqueous medium was investigated. The surface adsorption of carboxylic acids (phthalic acid and the reaction intermediates) deactivates the catalyst. The regeneration by H2O2 treatment nearly restored the activity, whereas washing with solvents as well as thermal treatment showed poor regeneration. The cause of deactivation of Degussa P25 titanium dioxide (TiO2) during photocatalytic degradation of phthalic acid in aqueous medium was investigated. Various regeneration methods, such as washing with solvents, hydrogen peroxide (H2O2) and thermal treatment were attempted to find the best technique for regeneration of spent catalyst. The deactivation and regeneration of TiO2 was monitored using XRD, FTIR, CHNO analysis, zeta potential measurement and surface area analysis. The surface adsorption of phthalic acid and the reaction intermediates deactivates the catalyst. The regeneration by H2O2 treatment nearly restored the activity, whereas washing with solvents and thermal treatment showed poor regeneration.