Uv Lamp Assisted Decomposition Of Dyes Over Iron-modified Diatomite In The Presence Of Tio2

Résumé: The present study deals with the photodegradation ( photocatalytic degradation ) in the environment of a textile industrial dye the Vat Green 03 Indanthrene according to pH levels , titanium dioxide TiO2 ( Degussa P25 ) and Vat Green 03 Indanthrene dye concentration irradiated under UV transilluminator lamp. The Vat Green 03 Indanthrene has a chemical formula C31H15NO3 .The titanium dioxide TiO2 ( Degussa P25 ) was used as a catalyst with a co-adsorbent, which was essentially a rock formed by accumulation of diatoms frustules called « diatomite or Kieselgühr » from the a deposit in Sig region in the North-West of Algeria, which was advantageous as it was locally available and less expensive. The diatomite raw material of Sig which was to be modified by a Ferrihydrite of the raw diatomite (DB) by adding iron (II) chloride tetrahydrate in various concentrations leading to an increase of the specific surface area through the treatment with Sodium Hydroxide ( NaOH ) of the raw diatomite ( DB ) which partially dissolved in the NaOH solution. The resulting element was (DMF1) and the characterisations were carried out through x-rays fluorescence (XRF), X-ray diffraction ( XRD ) and Fourier’s transformed infrared attenuated total reflection spectroscopy, IR-ATR ). The diatomite modified by Ferrihydrite without and with calcination at 600°C contained iron (III) oxide in different phases which are: Ferrihydrite, hematite, maghemite, lepidocrocite, goethite, schwertmannite, ferroxhyte, akaganeite, ferroxide and magnetite. The sample examined by scanning electron microscope (SEM) showed: Raw diatomite (DB): centric particles of 0.09-0.5 μm diameter length and pinnate particles of 2.5-3.5 μm length. Diatomite modified by Ferrihydrite (DMF1): centric particles of 3-6 μm diameter and the pennate particles of 4-9 μm length. The absorbance measurement of Vat Green 03 Indanthrene was carried out by UV-Visible spectrophotometry. For the mixture (DMF1+TiO2), the irradiation in 60 min time of photocatalytic reaction was at a better colour remove level of about 93 % at pH = 4, pH = 7 and pH = 10 it was verified that, it was verified that in pH = 4, pH = 7 and pH = 10 at kinetics rates constants kap were : 7,37x10-2 min-1 , 8,13x10-2 min-1 and 6,8x10-2 min-1 respectively.

Publié dans la revue: Algerian Journal of Engineering Research