Comparison of the degradation of p-hydroxybenzoic acid in aqueous solution by several oxidation processes

• Published in: Chemosphere (Oxford) Vol. 42; no. 4; pp. 351 - 359
• Main Authors: Beltran-Heredia, Jesus, Torregrosa, Joaquin, Dominguez, Joaquin R., Peres, Jose A.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.02.2001; Elsevier
• Subjects: AOPs; Applied sciences; Exact sciences and technology; Fenton's reagent; Hydrogen Peroxide - pharmacology; Industrial wastewaters; Iron - pharmacology; Kinetics; Oxidation-Reduction - drug effects; Ozonation; p-Hydroxybenzoic acid; Parabens - chemistry; Photolysis; Pollution; Solutions; Wastewaters; Water treatment and pollution; Ozonation; p-Hydroxybenzoic acid; Kinetics; Photolysis; Fenton's reagent; AOPs; Hydrogen peroxide; Combined process; Iron II; Photocatalysis; Chemical reaction kinetics; Ozonization; Ultraviolet radiation; Carboxylic acid; Industrial waste water; Phenols; Fenton reaction; Aromatic compound; Physicochemical purification; Oxidation; Rate constant; Waste water purification; Titanium oxide; Photooxidation; Comparative study; Photochemical degradation
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/S0045-6535(00)00136-3

A comparative study is made of 12 methods of chemical oxidation applied to degrading p-hydroxybenzoic acid in aqueous solution. The oxidation processes tested were: UV, O 3, UV/TiO 2, O 3/Fe 2+, O 3/H 2O 2, O 3/UV, UV/H 2O 2, H 2O 2/Fe 2+, H 2O 2/Fe 2+/O 3, UV/H 2O 2/O 3, H 2O 2/Fe 2+/UV and O 3/UV/H 2O 2/Fe 2+. The 12 processes were ranked by reactivity. In a kinetic study, the overall kinetic rate constant was split up into three components: direct oxidation by UV irradiation (photolysis), direct oxidation by ozone (ozonation), and oxidation by free radicals (mainly OH ).