title: Degradation of azo dye acid red B on manganese dioxide in the absence and presence of ultrasonic irradiation.
abstract: Degradation of azo dye acid red B (ARB) on MnO(2) in the absence and presence of ultrasonic irradiation (sonication) has been investigated. The effect of initial pH, anions (Cl(-), NO(3)(-), SO(4)(2-)), and saturated gas (argon/oxygen) has been studied. The experimental results show that decolorization of the dye on MnO(2) is highly pH dependent, with increasing decolorization efficiencies at decreasing pH values. The SO(4)(2-) and NO(3)(-) ions are observed to suppress the adsorption of ARB on MnO(2) dramatically, suggesting competitive nature with the dye. Sonication accelerates decolorization and mineralization of the dye. And oxygen used as saturated gas is more favorable for mineralization of the dye than argon. The average particle diameter of MnO(2) decreases from 47.5 to 3.19 microm after sonication.
authors.affiliation: State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Jiantuan
authors.initials: J
authors.lastname: Ge
authors.forename: Jiuhui
authors.initials: J
authors.lastname: Qu
mesh_terms: D000327:Adsorption; D005456:Fluorescent Dyes / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D017895:Manganese Compounds / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D012235:Rhodamines / Q000737:chemistry*; D014465:Ultrasonics; D018508:Water Purification / Q000379:methods*
chemical_list: D005456:Fluorescent Dyes; D017895:Manganese Compounds; D010087:Oxides; D012235:Rhodamines; C022027:lissamine rhodamine B; C016552:manganese dioxide