A combination of ultrasound and a bio-catalyst: removal of 2-chlorophenol from aqueous solution

• Published in: Ultrasonics sonochemistry 2006, Vol.13 (1), p.37-41
• Main Authors: Entezari, Mohammad H., Mostafai, Masoud, Sarafraz-yazdi, Ali
• Format: Article
• Language: English
• Subjects: 2-chlorophenol; Biological and medical sciences; Catalysis; Cavitation; Chemical Fractionation - methods; Chemistry; Chlorophenols - chemistry; Chlorophenols - isolation & purification; Chlorophenols - radiation effects; Degradation; Dose-Response Relationship, Radiation; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General and physical chemistry; Horseradish Peroxidase - chemistry; Horseradish Peroxidase - radiation effects; Horseradish peroxides; Hydrogen Peroxide - chemistry; Hydrogen Peroxide - radiation effects; Mechanisms. Catalysis. Electron transfer. Models; Molecular biophysics; Physical chemistry in biology; Physical chemistry of induced reactions (with radiations, particles and ultrasonics); Radiation Dosage; Solutions; Sonication; Sonolysis; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry; Ultrasonic chemistry; Water - chemistry; Water Pollutants, Chemical - isolation & purification; Water Pollutants, Chemical - radiation effects; Water Purification - methods
• ISSN: 1350-4177; 1873-2828
• DOI: 10.1016/j.ultsonch.2004.11.002

Phenolic compounds have become a cause for worldwide concern due to their persistence, toxicity and health risks. This paper reports a three-step approach to remove 2-chlorophenol from dilute aqueous solution and compares each technique. The first step utilizes Horse Radish Peroxidase (HRP) in presence of hydrogen peroxide to oxidize this organic pollutant (enzyme treatment). For a more efficient removal of 2-chlorophenol, it is necessary to add the enzyme solution gradually to the contents of the reactor instead of rapid addition. The second step, involving ultrasonic waves eliminated 2-chlorophenol through hydroxyl radical generated by the cavitation process (sono-degradation). In the third step, a combination of ultrasonic waves and enzyme was used (sono-enzyme degradation). It should be mentioned that, the enzyme can be active in the presence of ultrasonic waves under the proper sonication. The degradation has been studied at different temperatures, intensities of irradiation, and concentrations of enzyme. The rate of degradation exhibited pseudo-first order behavior and the combination method was more effective than sonolysis and enzyme treatment individually.