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Show presented above for T C B and M C B z. The PIC data for T C E is summarized in Figures 7 and 11 for the photothermal and thermal exposures, respectively. These data show that only carbon tetrachloride was quantified as a major PIC. In contrast to the data presented above, these data show that this product was formed at a slightly higher yield from the photothermal process (18.9%) as compared to the thermal exposure (15.0%). However, in both cases this product was effectively destroyed by 700°C. It should be noted that phosgene was also observed under both conditions and is likely to be a major product with yields comparable to carbon tetrachloride. Unfortunately, reliable quantitative data is not yet available for this compound, so it is not reported here. Carbon balances at 600°C (excluding phosgene) showed that 8 7 % (photothermal) and 1 0 1 % (thermal) of the total carbon was recovered. This suggests that this compound may indeed be a relatively major PIC, and further analysis of this product is planned. Figures 8 and 12 summarize the PIC data from the photothermal and thermal decomposition of D C B z , respectively. Carbon balances at 675°C showed that 1 2 4% (photothermal) and 131% of the total carbon was recovered, so all major PICs have been accounted for. Figures 8 and 12 show that D C B z generates monochlorobenzene and 2- chlorophenol as major PICs under both exposure conditions. In the photothermal tests, monochlorobenzene reached a maximum yield of 1.30% at 600°C and 2-chlorophenol reached 1.1% at 650°C. These same product were observed as the major PICs from the thermal exposures with monochlorobenzene reaching a maximum yield of 0.48% at 675°C and 2-chlorophenol reached 1.1% at 650°C. Under both exposure conditions the PICs were effectively destroyed by 700°C. Reviewing the sum of all the PIC data presented above it is difficult to draw definitive conclusions on the ability of the photothennal process to suppress the formation of organic products. However, some important observations can be made. The data for PICs from T CB presented here, as well was data from other high molecular weight compounds such as chlorinated dioxins, illustrate that the photothennal process can effectively reduce, or even eliminate, the formation of high molecular weight products such as chlorinated dibenzodioxins and furans. The data from the decomposition of M C B z even more strongly suggests that the photothermal process can greatly simplify the distribution of major organic products as compared to a thermal process. Interestingly, this was not found to be the case for the decomposition of D C B z . This suggests that the nature of the illumination source (pulsed laser in the case of M C B z as compared to continuous xenon arc for D C B z ) can significantly impact the efficiency of the photothennal process. Furthennore, it is clear that the photothennal process accomplishes much more than simple sequential dehalogenation of the waste feed or conversion to other organic products as has often been reported with other photochemical processes.[1,2,6] Finally, the photothennal process 12 111-19 |