Rapid Ultrasound Assisted Reduction of Azo Dyes for Screening Banned Aromatic Amines

Ultrasound‐assisted reduction of bis azo dye into aromatic amines on natural textile fibres: A greener approach

“…This arrangement is very similar to the ultrasound-assisted reduction (UAR) set-up described in another study. 14 UAR was performed at a fixed internal temperature of 70°C for 10 and 15 minutes in separate trials for each matrix. The rest of the procedure is very similar to the standard method for textile materials, BS EN 14362-1: 2012 (E), as outlined above.…”

“…The reduction vessel was placed in the middle of the sonicator bath at an identical water level and depth in all of the trials to lessen exposure differences. This arrangement is very similar to the ultrasound‐assisted reduction (UAR) set‐up described in another study 14 . UAR was performed at a fixed internal temperature of 70°C for 10 and 15 minutes in separate trials for each matrix.…”

“…16 The high pressures, temperatures and free radical generation account for the vast applications of ultrasonication, including dissolution, cleaning, extraction, derivatisation, degassing, homogenisation, leaching and nebulisation processes. Ultrasonication has also been employed for the treatment of textile effluent and dye degradation, both alone 14,18 and in combination with other aids and techniques. 19,20 Extensive literature has been published on the determination of banned aromatic amines using a variety of techniques and in diverse substrates.…”

“…Among the techniques most commonly employed in green chemistry are microwave heating 13 and ultrasonication 14 for enhancing the efficiency of several derivatisation reactions and extractions 15 . Sounds with a frequency above human audible range (1‐16 kHz) are classified as ultrasonic.…”

“…These test procedures have some stages in common: primarily the reduction (under precise conditions) followed by selective extraction, final detection and quantitative analysis. The reduction of intact azo dyes (not applied on a matrix), by microwave‐ 13 and ultrasound‐assisted chemical reduction, 14 have been presented in our earlier studies. The current work addresses ultrasound‐assisted (chemical) reduction of textile materials, cotton, linen and wool, dyed with a preselected azo dye.…”