Application of electrochemically generated ozone to the discoloration and degradation of solutions containing the dye Reactive Orange 122

作者：Santana Mario H P; Da Silva Leonardo M; Freitas Admildo C; Boodts Julien F C; Fernandes Karla C; De Faria Luiz A^*

来源：Journal of Hazardous Materials, 2009, 164(1): 10-17.

DOI：10.1016/j.jhazmat.2008.07.108

• Ozone
• Electrochemistry
• Discoloration kinetics
• Textile dye degradation

Aqueous solutions containing the commercial azo dye Reactive Orange 122 (RO122) were ozonated in acid and alkaline conditions. Ozone was electrochemically generated using a laboratory-made electrochemical reactor and applied using semi-batch conditions and a column bubble reactor. A constant ozone application rate of 0.25 g h(-1) was used throughout. Color removal and degradation efficiency were evaluated as function of ozonation time, pH and initial dye concentration by means of discoloration kinetics and COD-TOC removal. Experimental findings revealed that pH affects both discoloration kinetics and COD-TOC removal. A single pseudo-first-order kinetic rate constant, k(obs), for discoloration was found for ozonation carried out in alkaline solutions, contrary to acidic solutions where kobs depends on ozonation time. COD-TOC removal supports degradation of RO122 is more pronounced for alkaline conditions. Evaluation of the oxidation feasibility by means of the COD/TOC ratio indicates that the ozonation process in both acid and alkaline conditions leads to a reduction in recalcitrance of the soluble organic matter.

• 出版日期2009-5-15