Destruction of TNT and RDX residues and devices

Concentrations of TNT and RDX in soil (10%) decomposed similar to the neat explosive. First-order rate constants ranged from 1.14 × 10 -7/sec (100°C) to 4.42 × 10-4/sec (250°C) for soil with 10% TNT compared to neat TNT [1.21 × 10-7 (100°C) and 7.78 × 10-5/sec (250°C)]. The 10% RDX is soil had rate constants that ranged from 1.86 × 10-5/sec (175°C) to 4.60 × 10-4/sec (210°C) compared to neat RDX [3.01 × 10-5/sec (175°C) and 1.03 × 10-3/sec (175°C). Low concentrations of TNT and RDX (i.e. 0.1%) decomposed faster than the neat explosives with rate constants ranging 2.81 × 10-6/sec (100°C) to about 3 × 10 -3/sec (250°C) for TNT and 2.12 × 10-3/sec (175°C) and 2.68 × 10-3/sec (210°C) for RDX. Migration studies suggested TNT was susceptible to sublimation/evaporation at 250°C. Between 2% and 8% of TNT from soil condensed onto walls of glass capillary above the contaminated soil column. Sublimation of RDX was less than 1%. From 7% to 14% of the TNT had migrated into clean soil while less than 2% of RDX in soil columns migrated into the clean soil at 250°C. Hypergolic reagents for TNT destruction included diethyl triamine (DETA), ethylene diamine (EDA), propyl amine, dipropyl amine tripropyl amine, propyl diamine, hexamethylene diamine (HMDA) and tris(3-aminoethyl)amine (tris). DSC of TNT with amines exhibited exotherms at 160°C to 180°C. TNT with borohydride produced an exotherm at a relatively high temperature of about 290°C. With both amine and borohydride temperature of the exotherm decreased significantly to about 83°C. Heat releases were largest when borohydride was present. Rate constants for tertiary and secondary amines reacted more slowly than primary amines (i.e. first-order rate constants of less than 10−13/sec for tertiary amines versus about 10-7/sec for primary amines)