Evaluation of hydroxyl radical pathway and kinetic process for bubbling ozonation of methylene blue as reference compound. Issue 23 (14th May 2016)

• Record Type: Journal Article
• Authors: Zhang, S.; Wang, D.; Fan, P.P.; Sun, L.P.
• Is Part Of: Desalination and water treatment. Volume 57:Issue 23(2016)
• Page Start: 10616
• Page End: 10625
• Publication Date: 2016-05-14
• Subjects: Ozonation -- Bubble column -- Hydroxyl radical -- Kinetic process -- Degradation; Saline water conversion -- Periodicals; Saline water conversion; Water -- Purification; Periodicals; 628.167
• DOI: 10.1080/19443994.2015.1038592
• Languages: English
• ISSNs: 1944-3994

Abstract

Abstract: Ozonation experiments were conducted in a bubble column reactor taking methylene blue (MB) as model compound, where the role of solution pH and organic load as basic parameters of wastewater influencing pathway of hydroxyl radical ( ) and the kinetics were investigated. The relative significance of -pathway was evaluated compared to molecular ozone in both kinetics and degradation process. Results showed that, as solution pH increased from 5 to 11, the contribution of (labeled as θ ) got intensified from 0.05 up to 0.80 (apparent abundance proliferated up to 35.76 × 10 −7 M), giving rise to an exponential growth of pseudo-first-order rate constant as well as an enhanced mineralization. Reduction of initial organic concentration ([C]0, MB ) retarded chemical gas-to-liquid absorption of ozone and the global degradation of MB, while interestingly at the same time, the kinetic rate constant on MB decolorization accordingly began to grow up since the -pathway impact substantially got reinforced ( θ elevated from 0.80 up to 1.944 when [C]0, MB decreased from 80 to 20 mg L −1 under pH 11).