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This work examined the feasibility of ozone (O(3)) absorption by H(2)O(2) solution in a rotating packed bed (RPB). The O(3) removal efficiency was determined at various operating variables including RPB speed, gas flow rate, and liquid flow rate in three RPBs. For each RPB, the results demonstrated that the RPB speed positively affected the O(3) removal efficiency. Also, the O(3) removal efficiency increased with the liquid flow rate but decreased with the gas flow rate. Moreover, the obtained results indicated that the O(3) removal efficiency increased as the inner radius of the bed was increased and the outer radius of the bed was decreased. Furthermore, the developed method for O(3) absorption using H(2)O(2) solution could provide the removal efficiency of more than 95%. Consequently, the novel method would have a great potential in the removal of O(3) from the exhausted gases.

The removal of muconic acid (specifically trans-trans-butanedioc acid) with ozone from water has been studied for kinetics purposes. Concentrations of muconic acid of 4.4x10(-4)M are completely removed with ozone in less than 14 and 9 min at pH 3 and 7, respectively, and 3x10(-4)M of ozone in the gas. The positive influence of pH was due to the more reactive muconic acid dissociated form with ozone. The process can be described as a second order irreversible gas-liquid reaction developing in the moderate kinetic regime of absorption. At the experimental conditions investigated no free radical reactions are present and muconic acid is entirely oxidized by molecular ozone. Rate constants of the direct reaction between muconic acid and ozone were found to be 1.6x10(4) and 1.4x10(5)M(-1)s(1) at 20 degrees C, pH 3 and 7, respectively, according to film theory.

Extracting waterborne contaminants to ozone-loaded Volasiltrade mark245 (a siloxane solvent in which ozone is ten times more soluble than water) has been studied as a means of enhancing reaction kinetics and thus, providing more rapid wastewater decontamination. Investigation was carried out with respect to 2-chlorophenol and dichloromethane. Using a pilot scale continuous flow liquid-liquid/ozone water treatment system, 2-chlorophenol was extracted to the ozone-loaded solvent phase and considerable extents of destruction were achieved. However, the approach was demonstrated to yield slightly less destruction than direct gas contact for the same utilization of ozone and enhanced reaction kinetics were not shown to occur. This was suggested to be due to increased interfacial mass transfer resistance and/or the promotion of less destructive reaction pathways. Modification of the existing pilot system, by conversion from co- to counter-current solvent-loading, enabled greater dissolved ozone concentrations to be achieved within the solvent. Increasing the counter-current exchange column height to approximately 2.5m was suggested for achieving a near optimum level of performance. The liquid-liquid/ozone approach was demonstrated to be an effective means of indirectly exposing wastewater contaminants to concentrated ozone. As such the technology may be applicable as an alternative to direct gas contact in instances where the avoidance of contaminant sparging is desired (i.e. where contaminants are highly volatile, pungent and/or toxic) or foaming occurs.