chemická technologie --- barviva --- textilní barvířství

Ten textile dyes (azo-dyes (CI Disperse Red 50, CI Direct Yellow 44, CI Reactive Blue 19, CI Reactive Blue 4, 1:1 metal complex CI Acid Blue 158, 1:2 metal complex CI Acid Red 213 and CI Acid Yellow 11), anthraquinone dyes (CI Disperse Red 121), oxazine dyes (CI Direct Blue 106) and nitro dyes (CI Disperse Yellow 42). were photocatalytically treated for colour removal in TiO2 suspension. Their decolouration rates were compared to the standardised methods; flocculation and coagulation. It was demonstrated the azo dye (CI Acid Red 213) and oxazine dye (CI Direct Blue 106) were highly degraded by photocatalysis with decolourization of 50 % after 15 min and 30 min and 84 % after 60 min with azo dye (CI Acid Yellow) being not degraded - from 5 - 30 min was 50 % darker and gradually back to the original (standard 100%) colour in 40 / 60 min. Disperse dyes on photocatalytic degradation gained more weight becoming darker after 30 min, which could be due photocatalytic degradation of auxiliary (dispersing agents) agents. The results indicate that photocatalytic colour degradation on CI Acid Red 213 and CI Direct Blue 106 was faster than on standardised methods.

Photocatalysis application in waste water treatment processes