Nanotechnology for waste water treatment: Comparative Study of Photodegradation of the Textile AZO Dyes by NANO-TIO2 & MWCNTS/NANO-TIO2 Photocatalysts

The photocatalytic degradation processes are gaining importance in the area of wastewater treatment, not only in academics also in industries, since these processes result in complete mineralization with operation at mild conditions of temperature & pressure. In this new era of nanotechnology Carbon based TiO2 composites have attracted much attention and become a very active field of research due to their unique properties & promising applications for the big problem of pollution. Our work deals with the comparison between photo-catalytic degradation of some textile Acid dyes using nano sized TiO2 & MWCNT-TiO2 thin films coated on various substrates. The synergistic effect has observed for nanocomposites of MWCNT/TiO2 on the photocatalytic degradation of acid-azo dyes. The higher photo-catalytic activity of the MWCNT-TiO2 composites might be attributed to the homogenous distribution of MWCNT-TiO2 complexes and play important role as an energy sensitizer for improving the quantum efficiency & a charge transfer of the MWCNT. From the experimental data it can be concluded that, the new hybrid MWCNTs/TiO2 composite are about 18 – 22 % efficient than pristine TiO2 as a photocatalyst.