Mathematically Determined Scavenger Impacts during Ozonolysis of Oxalic Acid Waste Slurriesn– 15600.

摘要

A basic oxidant balance, including the primary chemical reactions associated with ozone, hydroxyl radical generation, scavengers and oxalate decomposition reactions was constructed and used to develop mathematical models to represent both steady state and time dependent changes in ozone concentrations, hydroxyl radical concentrations, scavenger concentrations and oxalate concentrations. Using the results from previous spent 1 wt% oxalic acid decomposition testing, a plot of 1/(oxalate reaction rate ) vs. 1/[C2O4 2-]) was used to estimate the initial hydroxyl radical generation values (i.e., g values) at time = 0. These g values are then compared for the different slurries to determine if the changes in g values are consistent with the scavenger dilution between the sequentially created slurries. Also considered as a potential scavenger is the CO2 arising from the oxalate decomposition. In this case the scavenger concentration and the carbon dioxide concentrations would be the same, and ks2 =ksc. Since the CO2 is created from the decomposition of oxalate, a standard equation can be used to compensate for time dependence of [C2O4 2-]. Using the results from previous spent 1 wt% oxalic acid decomposition testing, plots of oxalate concentration over time were used to determine time specific g values. The g values are then compared to determine how the values change throughput the oxalate decomposition. Using the results from previous spent 1 wt% oxalic acid decomposition testing, time dependent values are developed for “kg/ka” to show the relative significance of hydroxyl radical reacting with the scavenger vs decomposition of the oxalate.