processing mixtures of energetic materials found in a single type of munition:

• M1 propellant/tetrytol (105-mm M2 cartridge)

• M8 propellant/tetryl (4.2-inch, M2 cartridge)

• M28 propellant/Composition B4 (115-mm, M55 rocket)

The actual ratios of propellant to burster explosive in the munitions will be used. Hydrolysate products are also being analyzed for picrate, as recommended in the ACW I Committee report (NRC, 1999). LANL has hydrolyzed the following combinations with no major perturbations: tetrytol (TNT and tetryl); cyclotol (RDX and TNT); octol (HMX and TNT); and nitrocellulose, nitroglycerin, nitroguanidine, triple-base propellant, and HMX (Bishop, 2000). Processing perturbations such as foaming were managed and controlled using well-known engineering techniques.

Hydrolysis experiments at Pantex have shown that cyclotol (70 percent RDX and 30 percent TNT) and tetrytol (70 percent tetryl and 30 percent TNT) reacted within 1 hour and 3 hours, respectively, in 6 to 12 percent caustic. The metric for the completion of the reaction is the disappearance of solid material in the reactor (Belcher, 2000). The reaction time for the tetrytol was probably less than 3 hours, because the functional groups in the tetryl molecule, which are similar to those in TNT and RDX, should react at similar rates. However, only a lower bound on the rate of tetrytol destruction is available, because no observations were made before 3 hours had elapsed. Observations made after 1 hour for cyclotol showed that all solids had been consumed.

The NSWC will conduct calorimetric studies to determine the heat of reaction for hydrolysis reactions with various concentrations of caustic. This information will be used to develop strategies for reaction controls and to prevent runaways and upsets (Bonnett, 2000).

The following reaction parameters are being determined for each energetic material by accelerating rate calorimetry:

• temperature of the maximum self-heating rate

• dependence of reaction rate on pressure and temperature

• rate of pressure and temperature increase

• heat of reaction

• moles of gas evolved per unit mass of energetic material

• activation energy of the reaction

• reactor cooling requirements

This information will be useful for numerical modeling and simulation of the hydrolysis reaction process.

Prior to Demonstration I, some attempts had been made to hydrolyze energetic materials on a large scale. RAAP (along with the Pantex Plant) produced the hydrolysates used during Demonstration I and the EDS tests in the ACWA program. RAAP was also expected to produce hydrolysate from M28 surrogate for the EDS program.

RAAP had manufactured M28 surrogate propellant specifically for the preparation of hydrolysate. For environmental reasons, the surrogate did not contain lead stearate, which is normally included in M28 propellant as a burn-rate modifier. The propellant was prepared in grains in the shape of right circular cylinders, 1/16 inch in diameter by 1/16 inch long.

Some of the problems that might be encountered in a large-scale operation were illustrated by a recent upset at RAAP. On October 14, 2000, hydrolysate from M28 surrogate propellant was being prepared when the piping of the recirculation loop ruptured, causing significant damage to the equipment (described later in this chapter).

Because the start of the EDS test program on energetics hydrolysis was delayed, the testing at HAAP had generated only limited data at the time this report was prepared. Energetic materials representative of the materials in the Pueblo stockpile had not yet been tested in the full-scale reactor at HAAP. As of January 1, 2001, only two Composition B hydrolysis runs had been completed. In one run, 200 lb of Composition B were hydrolyzed, and in the other, 500 lb were hydrolyzed. A detailed analysis of the hydrolysate composition as a function of time during these runs had not been completed by February 1, 2001; however, useful information was generated about the systemization (preoperational testing) of a full-scale hydrolysis reactor. At this point, the committee can comment only on the test plan and the preliminary results from these two runs. The committee believes that the test plan is well designed to determine acceptable parameters on the full-scale reactor at HAAP.

Systemization of the 2,000-gallon hydrolysis reactor at HAAP was completed within 4 months. Composition B, which is produced at HAAP and is readily available, was chosen for the initial experiments. The disposal of hydrolysate is covered under existing permits for handling waste from the production of Composition B. Because foaming is difficult to control in Composition B, the two test runs with this material provided a good test of the efficacy of measures designed to control foaming.

The problems that occurred were typical of any start-up operation. For example, the Acrison feeder, which is used to