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Cyclophosphamide is a hazardous cytostatic drug, which should be removed from wastewaters before disposals. Ozonation slowly inactivates this substance, requiring long reaction times to obtain degradation. In this paper, different advanced oxidation processes (AOPs) are studied for cyclophosphamide oxidative degradation in aqueous medium: ozone at several basic pH values, ozone/hydrogen peroxide at neutral and basic pHs with the addition of the peroxide at the beginning of ozonation. The influence of ozone concentration in the gas phase and gas flow is also discussed. Results show that, under the experimental conditions studied, the radical mechanism acting in the AOPs rapidly degrades cyclophosphamide. Additionally, second-order rate constants kd and kOH were determined for direct (molecular) and indirect (radical) reactions. Finally, reactions were carried out with the aim of isolating and identifying some of the degradation products. From ozonation at pH 9, 4-ketocyclophosphamide was identified as the main reaction product. [ABSTRACT FROM AUTHOR]

A method that uses ozone for the decolorization step in cane sugar refining is presented. It concerns an important and new application of ozone in the field in the cane sugar industry. Very efficient decolorization of clarified liquors was obtained at different scales. To obtain satisfactory decolorization, suitable treatment operation conditions were established. In the pilot plant study, refined sugar of high purity was obtained, which fulfilled the international quality requirements. At the laboratory scale, a kinetic study for the process has been developed in a continuous system with the use of Danckwert's model. The effective kinetic coefficient (βO 3 ) values were between 10 5 and 10 6 L/mol·s. [ABSTRACT FROM AUTHOR]