Photodegradation of azodyes: comparison of different catalytic systems and control of the effective mineralisation.
Three different azodyes were used as target molecules to test the efficiency of the photodegradation process catalysed by titanium dioxide under UV irradiation. A comparison of different catalytic systems was performed using the catalyst both free in solution (system I) and immobilised in a polymeric membrane (system II). Iron oxalate and a conducting polymer (polyaniline, PA) were added to the I and II systems respectively to check an eventual synergetic effect. The research evolved through three different steps involving each one the use of a different analytical method. Shortly, the UV spectrophotometry were preliminarily used to monitor the bleaching process and allowed to choose the best catalytic system, HPLC and GC/MS were used to monitor the appearance and disappearance of the photodegradation intermediates and, lastly, the effective mineralisation was tested by an indirect ICP (Inductively Coupled Plasma) determination of the produced carbon dioxide.
Campanella
Luigi
L
Dept of Chemistry, University La Sapienza, P le A Moro 5, 00185 Rome, Italy. luigi.campanella@uniromal.it
Giardina
Isabella
I
Russo
Mario Vincenzo
MV
Sammartino
Maria Pia
MP
Visco
Giovanni
G
D001391:Azo Compounds / Q000737:chemistry*; D004396:Coloring Agents / Q000737:chemistry*; D010777:Photochemistry; D013783:Textile Industry; D014025:Titanium / Q000737:chemistry; D014466:Ultraviolet Rays; D018508:Water Purification / Q000379:methods
D001391:Azo Compounds; D004396:Coloring Agents; C009495:titanium dioxide; D014025:Titanium