| Abstract
| - The reaction kinetics and product distributions for thereduction of 2,4,6-trinitrotoluene (TNT) by granular iron metal(Fe0) were studied in batch experiments under a varietyof initial concentrations of TNT and Fe0. Although the kineticsof TNT disappearance were found to behave in accordwith the standard theory for surface-mediated reactions,a complex relationship was found between the initialconcentrations of TNT and Fe0 and the appearance of theexpected nitro reduction product, 2,4,6-triaminotoluene(TAT). TNT was completely converted to TAT only whenthe initial concentration of TNT was low and/or the initialconcentration of Fe0 was high. Mathematical analysisof a range of generic reaction schemes that produce stableend products in addition to TAT showed that (i) surfacecomplexation of TAT is insufficient to describe all of our dataand (ii) polymerization reactions involving TAT and/orvarious reaction intermediates are the likely source of theincomplete conversion of TNT to TAT at high initial TNTconcentration and low Fe0 concentration. The relationshipbetween TAT production and reaction conditions isshown to imply that passivation due to reaction productsis more likely when the ratio of initial TNT concentration toFe0 concentration is high and, therefore, that passivationrates observed at the laboratory scale are likely to be fasterthan those which would be observed at the field scale.
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