title: Comparison of photocatalytic degradation of dyes in relation to their structure.
abstract: The photocatalytic degradation of a series of six acid dyes (Direct Red 80, Direct Red 81, Direct Red 23, Direct Violet 51, Direct Yellow 27, and Direct Yellow 50) has been tested compared in terms of color removal, mineralization, and toxicity (Lactuca sativa L. test) after photocatalysis on immobilized titanium dioxide. The dyes were examined at their natural pH and after hydrolysis at pH 12. Results show that hydrolysis decreases strongly the efficiency of color removal, that full mineralization takes much longer reaction time than color removal, and that toxicity is only very partially reduced. Some structural parameters, related to the structure and the topology of the dye molecules, could be correlated with the apparent color removal rates at natural pH.
authors: Laboratoire Réactions et Génie des Procédés-CNRS, Université de Lorraine, 1 rue Grandville, BP 20451, 54001, Nancy cedex, France.
authors: R
authors: R
authors: Byberg
authors: J
authors: J
authors: Cobb
authors: L Diez
authors: LD
authors: Martin
authors: R W
authors: RW
authors: Thompson
authors: T A
authors: TA
authors: Camesano
authors: O
authors: O
authors: Zahraa
authors: M N
authors: MN
authors: Pons
mesh_terms: D000813:Anilides / Q000737:chemistry*; D001391:Azo Compounds / Q000737:chemistry*; D002384:Catalysis; D004396:Coloring Agents / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D009281:Naphthalenes / Q000737:chemistry; D009282:Naphthalenesulfonates / Q000737:chemistry*; D010782:Photolysis; D014025:Titanium / Q000378:metabolism; D018675:Toxicity Tests / Q000379:methods; D062065:Wastewater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry
chemical_list: D000813:Anilides; D001391:Azo Compounds; D004396:Coloring Agents; D009281:Naphthalenes; D009282:Naphthalenesulfonates; D014025:Titanium; D062065:Wastewater; D014874:Water Pollutants, Chemical; C502684:direct yellow; C506598:1-(2-methoxy-5-nitrophenylazo)-2-hydroxy-3-(3-nitrophenylcarbamoyl)naphthalene; C009798:C.I. direct red 80; C009495:titanium dioxide; C062246:Direct Red 81; C572782:Direct Violet 51