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Mineralization of sulfolane in aqueous systems by CaO 2 /O 3 and CaO/O 3 was investigated in this study. If 1.6 g/L of oxidants (CaO 2 and CaO) were used along with 5 L/min of O 3 in a batch reactor, degradation of sulfolane followed a pseudo-first order kinetics model. Both sulfolane and TOC were totally removed in less than 40 and 150 min respectively. For these treatments, the pH of the aqueous solutions was above 11, which made O 3 more effective in removing sulfolane. However, the high pH of the solution didn't improve TOC removal. For TOC removal the presence of CaO 2 and CaO was necessary. Once these conditions were optimised in the lab, field experiments were designed and evaluated to treat contaminated ground water samples. The field tests were successful in mineralization of sulfolane within a reasonable time (4 h). Sulfolane degradation took 150 min in these experiments. The pH of the water samples was brought to near neutral (pH = 6.5) by bubbling CO 2 ., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

This study investigates the degradation of sulfolane in aqueous system by (NH 4 ) 2 S 2 O 8 /UVC and (NH 4 ) 2 S 2 O 8 /O 3 /UVC. While bubbling O 3 significantly decreased the reaction time, the experimental results in both cases were consistent: firstly, the degradation of sulfolane followed pseudo-first order kinetic models, secondly, the reaction rates were affected by persulfate dosages, UV light intensity, initial pH and concentration of carbonate/bicarbonate present. Low concentration of chloride (less then 100 ppm) had no effect on the reaction rate. Application of (NH 4 ) 2 S 2 O 8 /O 3 /UVA for degradation of sulfolane was also investigated. It was found that for higher sulfolane degradation kinetics, higher concentrations of persulfate was required under UVA irradiation. Finally, (NH 4 ) 2 S 2 O 8 /UVC was evaluated for its applicability for degradation of sulfolane in groundwater samples., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

In this study, a fixed bed flow through UVA-LED photoreactor was used to compare the efficiency of ozone, photocatalysis and photocatalysis-ozone degradation, and mineralization of two pure pesticides, 2,4-dichlorophenoxyacetic acid (2,4-D) and 2-methyl-4-chlorophenoxyacetic acid (MCPA), and a commercial one, Killex®. For the degradation of the parent compounds, ozone-based processes were more effective. While for mineralization, photocatalytic processes were more effective. Photocatalytic ozonation was the most efficient process for both the degradation and mineralization of the parent compounds. The degradation rates and mineralization by photocatalytic ozonation were higher than the summation of the corresponding rates by ozonation and photocatalysis, indicating a symbiotic relationship.Overall, the photocatalytic ozonation process with the fixed bed TiO 2 reduces the time needed for the degradation and mineralization of the pesticides, reduces the costs of powder catalyst separation and overcomes the reduced efficiency of immobilized catalysts, which makes the process quite attractive for practical applications.

In this paper, degradation of bisphenol S (BPS) in spiked water and postsecondary-treated wastewater by a variety of oxidation processes was investigated in a flow-through reactor. Kinetics of degradation in O3, ultraviolet ðUVÞ=O3, UV=H2O2, and UV=O3=H2O2 were determined and reported. The degradation of BPS by O3 alone was competitive with the UV-promoted methods. An increase in BPS loss with O3 was observed in postsecondary-treated wastewater, demonstrating its potential application as a treatment method for BPS. Total organic carbon (TOC) as an indicator of the extent of organic compound mineralization and sulfate as a by-product produced during degradation were measured. It was noted that although the loss of BPS was similar in the UV=O3=H2O2 and the O3 processes, the overall mineralization rate was different, indicating that the combination technique offers a more efficient system in terms of overall mineralization rate. The UV=O3=H2O2 process was the most effective and led to complete mineralization of 50 mg=L BPS within 90 min in both spiked water and postsecondary-treated wastewater. [ABSTRACT FROM AUTHOR]