The Combustion of Highly Fluorinated Organic Compounds

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itself. As a result there are definite constraints in both the lean and rich regions on where destruction can take place. Practically, it may well mean that during incineration results may show wide variations unless considerable care is taken. In comparison to the perfluoromethane, the difference between the other three fluorinated compounds are not very large. It is interesting that the ordering in terms of time to achieve 99% destruction are changed in going from the 900 to 1200 K simulations. Clearly the concept of incinerability must be treated with care and probably fine distinctions are not justified. On the other hand perfluoromethane should be an excellent surrogate. The capability of destroying this compound certainly guarantees the destruction of practically all other organic compound. However, it may well be that this represents a severe overkill and that other compounds will have a more extensive destruction range and thus lead to the necessity of less severe conditions. Figures 1-4 does illustrate the basic problem with scales of incinerability. Only at the extremes in the range of possible stoichiometries does it have real meaning and the chemistry come into play. On this basis one would expect that the nature of the fuel may play some role in this parameter. Indeed for some systems, the fuel itself may be a very suitable surrogate. It is interesting that for all except perfluoromethane the presence of the additive has the effect of accelerating the decomposition. This is seemingly contrary to their possible role as fire retardant. The explanation18 for this is that the action of fire retardant is to decrease the intensity of the radical concentration in the flame front as opposed to having any effect on the initiation process. The simulation result yields much information on the PICs that may be formed. However, for the reasons discussed earlier it must be incomplete and we are uncertain of the accuracy. Clearly there is much room for further work. It should be noted that simulations may well be only means by which one can developed any type of structure to predict or at least to systematize results on this very important issue. SUMMARY The chemistry of the incineration of simple highly fluorinated carbon have been described in terms of single step thennal reactions. Consequences have been deduced on 17