Raymond Flesner

• Los Alamos National Laboratory

In this work, we present model-based control and estimation algorithms developed to control the effluent composition for a hydrothermal oxidation reactor. The reactor is used to oxidize the organic compounds present in the hydrolysate solutions obtained from the destruction of HMX-based high explosives by base hydrolysis. The objective of the model...

Four TNT explosive formulations were treated with 1.5 M and 3 M solutions of sodium hydroxide (NaOH) at temperatures between 90°C and 150°C. The reaction time needed for over 99% conversion of the explosive compound was less than 5 minutes at 150°C for both Octol and Comp B, and less than 30 minutes at 90°C for Tritonal and Tetrytol. The TNT and Te...

Alkaline hydrolysis is used to convert high explosives to nonenergetic, aqueous compounds. Base hydrolysis of high explosives is exothermic (ΔHRXN = 2.3 kJ/g), and thermal runaway of the reaction is a possibility at elevated temperatures (>120 °C) where the rate of reaction is large. Thermal runaway could result in an accidental detonation of the e...

Alkaline hydrolysis is used to convert high explosives to nonenergetic, aqueous compounds. Base hydrolysis of high explosives is exothermic (ΔH(RXN) = 2.3 kJ/g), and thermal runaway of the reaction is a possibility at elevated temperatures (> 120 °C) where the rate of reaction is large. Thermal runaway could result in an accidental detonation of th...

The effects of agitation rate, air sweep rate, and reactor temperature in the production of PBX 9501, a plastic-bonded explosive molding powder, were investigated. These variables affected the agglomerate length, the agglomerate shape, and the bulk density of the molding powder, but had very little effect on the properties of pressed pieces made fr...

Bench-scale studies demonstrated the efficacy of hydrothermal oxidation for the treatment of wastes derived from the alkaline hydrolysis of the high explosive PBX 9404 (94% HMX, 3% nitrocellulose, and 3% chloroethyl phosphate). Specifically, chemical kinetics studies were used to deduce major global reaction pathways, and to develop a kinetic model...

The degradation of HMX-based high explosives (HMX, PBX 9404, and PBX 9501) with sodium hydroxide solutions is described. To obtain practicable reaction rates, the reaction was carried out in a pressurized reactor at temperatures up to about 155 C. Above about 70 C, mass transfer rates significantly affect the observed reaction rate. Therefore, a so...

We present the estimation techniques used to update the model parameters in a reduced kinetic model describing the oxidation-reduction reactions in a hydrothermal oxidation reactor. This model is used in a nonlinear model-based controller that minimizes the total aqueous nitrogen in the reactor effluent. Model reduction is accomplished by combining...

Sodium carbonate (Na2CO3) is identified as a hydrolysis reagent for decomposing HMX and HMX-based explosives to water-soluble, nonenergetic products. The reaction kinetics of Na2CO3 hydrolysis are examined, and a reaction rate model is developed. Greater than 99% of the explosive at an initial concentration of 10 wt % PBX 9404 was destroyed in less...

This paper describes the model-based control algorithm developed for a hydrothermal oxidation reactor at the Pantex Department of Energy facility in Amarillo, Texas. The combination of base hydrolysis and hydrothermal oxidation is used for the disposal of PBX 9404 high explosive at Pantex. The reactor oxidizes the organic compounds in the hydrolysa...

Los Alamos National Laboratory has demonstrated that many energetic materials can be rendered non-energetic via reaction with sodium hydroxide or ammonia. This process is known as base hydrolysis. A pilot scale reactor has been developed to process up to 20 kg of plastic bonded explosive in a single batch operation. In this report, we discuss the d...

Sodium carbonate has been identified as a possible hydrolysis reagent for decomposing HMX-based explosives to water soluble, non-energetic products. In this study, the reaction kinetics of sodium carbonate hydrolysis are examined and a reaction model is developed. The rate of hydrolysis is reaction rate limited, opposed to mass transfer limited, up...

A series of experiments at Los Alamos National Laboratory explored the efficacy of ammonium hydroxide solutions in converting HMX (cyclotetramethylene-tetranitramine, or Octogen) and HMX-based explosives to nonenergetic, nonhazardous materials. When 80 g of explosive was converted in a reactor operating at 85 psig pressure at 140 C, the principal g...

Hydrogen isotope exchange with adsorbed CHâOH and coadsorbed CO + Hâ (which form CHâO) was studied on a Ni/AlâOâ catalyst by temperature-programmed reaction and desorption (TPR, TPD). Since both CHâOH and CHâO are adsorbed on the AlâOâ support, but Hâ adsorbs and dissociates on the Ni surface, H atom spillover onto the AlâOâ surface is an important...

In dismantling weapons from stockpile reduction, environmentally acceptable methods to degrade the associated high explosive (BE) waste to non-energetic forms is a critical objective. Base hydrolysis appears to be a safe, simple, and inexpensive method for converting energetic materials (EN-MATs) into non-energetic materials. We have demonstrated t...

Temperature-programmed reaction was used to study hydrogenation of CO on Pt/Al2O3 and Pd/La2O3 catalysts. Coadsorbed CO and H2 form CH3O on the supports, and this CH3O hydrogenates faster than CO adsorbed on the metals. This spillover process may be responsible for the higher methanation activities observed with Al2O3 and La2O3 supports.

Temperature-programmed reaction and desorption (TPR, TPD) were used to study the formation and hydrogenation of CH3O on a 7.7% Pt/Al2O3 catalyst. Methoxy forms in an activated spillover process following CO and H2 adsorption on Pt, and adsorbed CH3O has the same desorption and reaction properties as adsorbed CH3OH. The CH3O species hydrogenates fas...

The desorption rate of CO from the Ni surface of a 5.1% Ni/Al2O3 catalyst was significantly increased by the presence of CH3O on the support. The CH3O was formed by CO and H2 coadsorption at 385 K. Reverse spillover of CH3O, as CO desorbed, maintained the Ni surface at a high coverage of CO and H2. This increased the rate of CO desorption because o...

The desorption rate of CO from the Ni surface of a 5.1% Ni/AlâOâ catalyst was significantly increased by the presence of CHâO on the support. The CHâO was formed by CO and Hâ coadsorption at 385 K. Reverse spillover of CHâO, as CO desorbed, maintained the Ni surface at a high coverage of CO and Hâ. This increased the rate of CO desorption because o...

Temperature-programmed reaction and desorption (TPR, TPD) for AlâOâ physically mixed with supported Ni catalysts show directly that one of the two CHâ peaks observed previously for TPR (CO hydrogenation) on Ni/AlâOâ catalysts results from spillover of adsorbed species onto AlâOâ and is not due to adsorption on unreduced Ni sites. Temperature-progra...

A pilot-scale, pressurized, base hydrolysis reactor has been designed and its construction is nearly completed. Up to 120 L of 1--6 M NaOH aqueous solutions will convert as much as 25 kg of consolidated, explosive pieces to non-energetic compounds. Temperatures approaching 155 C in the pressurized unit will reduce reaction times significantly for t...

Base hydrolysis in combination with hydrothermal processing has been proposed as an environmentally acceptable alternative to open burning/open detonation for degradation and destruction of high explosives. In this report, the authors examine gaseous and aqueous products of base hydrolysis of the HMX-based plastic bonded explosive, PBX-9404. The au...

Base hydrolysis in combination with hydrothermal processing has been proposed as an environmentally acceptable alternative to open burning/open detonation for degradation and destruction of high explosives. In this report, the authors examine gaseous and aqueous products of base hydrolysis of the HMX-based plastic bonded explosive, PBX-9404. They a...

Base hydrolysis in combination with hydrothermal processing has been proposed as an environmentally acceptable alternative to open burning/open detonation for degradation and destruction of high explosives. In this report, the authors examine gaseous and aqueous products of base hydrolysis of the HMX-based plastic bonded explosive, PBX-9404. The au...