title: A combination of ultrasound and a bio-catalyst: removal of 2-chlorophenol from aqueous solution.
abstract: 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.
authors.affiliation: Department of Chemistry, Ferdowsi University of Mashhad, 91775 Mashhad, Iran. moh_entezari@yahoo.com
authors.forename: Mohammad H
authors.initials: MH
authors.lastname: Entezari
authors.forename: Masoud
authors.initials: M
authors.lastname: Mostafai
authors.forename: Ali
authors.initials: A
authors.lastname: Sarafraz-Yazdi
mesh_terms: D002384:Catalysis; D005591:Chemical Fractionation / Q000379:methods; D002733:Chlorophenols / Q000737:chemistry* / Q000302:isolation & purification* / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D006735:Horseradish Peroxidase / Q000737:chemistry* / Q000528:radiation effects; D006861:Hydrogen Peroxide / Q000737:chemistry* / Q000528:radiation effects; D011829:Radiation Dosage; D012996:Solutions; D013010:Sonication; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification / Q000528:radiation effects; D018508:Water Purification / Q000379:methods*
chemical_list: D002733:Chlorophenols; D012996:Solutions; D014874:Water Pollutants, Chemical; D014867:Water; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase; C030683:2-chlorophenol