Case study of the sonochemical decolouration of textile azo dye Reactive Black 5

Simona Vajnhandl (Author), Alenka Majcen Le Marechal (Author)

Abstract

The decolouration and mineralization of reactive dye C.I. Reactive Black 5, a well-known representative of non-biodegradable azo dyes, by means of ultrasonic irradiation at 20, 279 and 817 kHz has been investigated with emphasis on the effect of various parameters on decolouration and degradation efficiency. Characterization of the used ultrasound systems was performed using calorimetric measurements and oxidative species monitoring using Fricke and iodine dosimeter. Experiments were carried out with low frequency probe type, and a high-frequency plate type transducer at 50, 100 and 150 W of acoustic power and within the 5-300 mgžL initial dye concentration range. Decolouration, as well as radical production, increased with increasing frequency, acoustic power, and irradiation time. Any increase in initial dye concentration results in decreased decolouration rates. Sonochemical decolouration was substantially depressed by the addition of 2-methyl-2-propanol as a radical scavenger, which suggests radical-induced reactions in the solution. Acute toxicity to marine bacteria Vibrio fischeri was tested before and after ultrasound irradiation. Under the conditions employed in this study, no toxic compounds were detected after 6 h of irradiation. Mineralization of the dye was followed by TOC measurements. Relatively low degradation efficiency (50% after 6 h of treatment) indicates that ultrasound is rather inefficient in overall degradation, when used alone.

Keywords

tekstilna industrija;odpadne vode;barvanje tekstilij;reaktivna barvila;azo barvila;razbarvanje odpadnih vod;ultrazvok;degradacija;kinetika razbarvanja;textile industry;wastewater treatment;textile dyeing;reactive dyes;azo dyes;decoloration;ultrasound;degradation;decoloration kinetics;oxidizing species;

Data

Language:	English
Year of publishing:	2007
Typology:	1.01 - Original Scientific Article
Organization:	UM FS - Faculty of Mechanical Engineering
UDC:	677.027.4:628.3:534-8
COBISS:	10568214
ISSN:	0304-3894
Views:	1652
Downloads:	79
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary keywords:	tekstilna industrija;odpadne vode;barvanje tekstilij;reaktivna barvila;azo barvila;razbarvanje odpadnih vod;ultrazvok;degradacija;kinetika razbarvanja;
URN:	URN:SI:UM:
Pages:	str. 329-335
Volume:	ǂVol ǂ41
Issue:	ǂiss. ǂ1
Chronology:	Mar. 2007
ID:	8718617