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technology combines the unrt operations of air stripping and oxidative <br /> decomposition in a single process which can be catalytically accelerated In the <br /> C-Sparge"' process, air and ozone are injected directly into groundwater through <br /> specially-designed spargers to create small "microbubbles" that have a very high <br /> surface area to volume ratio As these microbubbles rise within a column of <br /> water, they extract or "step" VOCs from groundwater by aqueous to gas <br /> partitioning Upon entering the microbubbles, the VOCs are rapidly oxidized by <br /> the process of Criegee oxidation The ozone contained within the bubbles reacts <br /> to decompose the chlorinated ethane molecule in an extremely rapid gas/liquid <br /> Phase reaction whose end products are carbon dioxide, very dilute hydrochloric <br /> acid, and water By increasing the ozone content within the bubbles, the rate of <br /> oxidation reaction is increased. Properly applied, the reaction has been used to <br /> rapidly detoxify halogenated VOCs (HVOCs), ethene and ethane derivatives and <br /> aromatic compounds in groundwater sources to below drinking water standards <br /> without producing unwanted harmful by-products (Kerfoot, 1997, Kerfoot, et al., <br /> 1998) <br /> Gas entering a small bubble of volume 47c? increases until reaching an <br /> asymptotic value of saturation. If we consider the surface of the bubble to be a <br /> membrane, a first order equation can be written for the monomolecular reaction <br /> d&=-k(Q-x) (1) <br /> dt <br /> Where- x = the time varying concentration of the substance in the bubble <br /> dx/dt = the rate of change of vapor concentration within the gaseous <br /> phase <br /> Q = the external concentration of the HVOC <br /> k = the absorption constant, set by Henry's partitioning coefficient <br /> If at time t=0, x=0,then <br /> X=Q(1-e k) (2) <br /> The constant k is found to be: <br /> -k= (3) <br /> Q-x <br /> Normally, the rate of adsorption reaches an asymptotic value because the <br /> concentration of x within the bubble becomes at equilibrium with the Henry's <br /> coefficient However, if ozone decomposes the incoming vapor, the mass <br /> removal rate will increase <br /> Since MTBE occupies a partitioning region similar to the common fuel <br /> aromatics benzene, toluene, methyl benzene, xylenes (Reisinger, et al., 1986), <br />