Behnajady - Assistant professor Department of Applied Chemistry, lslamic Azad University, Tabriz Branch,Tehran, Iran
Modirshahla - Associate professor Department of Applied Chemistry, lslamic Azad University, Tabriz Branch,Tehran, Iran
Shokri - Lecturer Department of Applied Chemistry, lslamic Azad University, Tabriz Branch,Tehran, Iran
Elham - Master of Science Department of Applied Chemistry, lslamic Azad University, Tabriz Branch,Tehran, Iran

Titanium dioxide nanoparticles with different average diameter of particles (8, 18 and 27 nm) and different crystal structure (anatase and rutile) were used for degradation of C.I. Acid Red 88 (AR88) as a model compound. The degree of degradation of AR88 by TiOz nanoparticles under irradiation of UV-light (254 nm) decreases with reducing Ti02 nanoparticles from 27 to 8 nm in anatase crystal structure. Ti02-P25 anatase and rutile (80:20) showed high photoactivity than other samples TiOz- UVI 00 (8 nm diameter and 100% anatase) and Ti02-Merck (27 nm diameter and 95% anatase).

Advanced oxidation processes (A0Ps)-Heterogenous Photocatalysis-Ti02 nanoparticles-Decolorization-C.I. Acid Red 27