Title: Photocatalytic decolouration of 2, 4-dinitrophenol by modified metal oxides/β-CD nanocomposites under UV-A light irradiation

Authors: P. Velusamy; S. Rajalakshmi

Addresses: Post-Graduate and Research Department of Chemistry, Ayya Nadar Janaki Ammal College, Sivakasi – 626 124, Tamilnadu, India ' Department of Chemistry, Erode Arts and Science College, Erode – 638 009, Tamilnadu, India

Abstract: The photocatalytic decolouration of 2, 4-dinitrophenol (DNP) in aqueous solution by modified metal oxides (MOs = TiO₂ and ZnO)/β-cyclodextrin (β-CD) has been investigated under visible light irradiation and the results are compared with bare MOs. The MOs and their modified forms are characterised by UV-DRS, PXRD and FE-SEM analyses. The obtained results show that β-CD does not affect the crystalline phase of MOs. The photocatalytic decolouration depends on various processing parameters like initial concentration of DNP, irradiation time, the amount of the catalysts used and pH of the medium. The rate of photocatalytic decolouration of DNP follows the pseudo-first order kinetics. COD results show that the DNP molecules are mineralised in acidic pH. From the results, it has been concluded that β-CD forms inclusion complex with DNP and adsorbed on metal oxide surfaces to enhance the photocatalytic decolouration of DNP.

Keywords: DNP; TiO2; titanium dioxide; ZnO; zinc oxide; beta-CD nanocomposites; photocatalytic decolouration; visible light irradiation; nanotechnology; modified metal oxides; 2, 4-dinitrophenol; DNP.

DOI: 10.1504/IJEWM.2016.078597

International Journal of Environment and Waste Management, 2016 Vol.17 No.3/4, pp.251 - 272

Accepted: 11 Apr 2016
Published online: 25 Aug 2016 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article