Ultrasonic desorption - a new regeneration technology

The feasibility of using ultrasound to enhance the desorption of tightly-bo und colorants from polymeric resin is discussed. It is shown that the desor ption rates of colorants were significantly increased by ultrasound at cert ain power and frequency settings. High frequency with low power ultrasound was selected to avoid breakage of the polymeric resin. Ultrasonic desorptio n is promoted by low temperatures and aerated liquid media. The desorption rate obtained without ultrasound appeared to be limited by pore diffusion. The rate can be increased by acoustic vortex microstreaming.