Application of Gas−Liquid Film Theory to Base Hydrolysis of HMX Powder and HMX-Based Plastic-Bonded Explosives Using Sodium Carbonate

Abstract

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 than 5 min at 150 °C. The primary products from Na2CO3 hydrolysis were nitrite (NO2), formate (HCOO-), nitrate (NO3 -), and acetate (CH3COO-) ions, hexamethylenetetramine, (hexamine: C6H12N4), nitrogen gas (N2), nitrous oxide (N2O), and ammonia (NH3). The rate of hydrolysis was characterized for HMX powder and PBX 9404 molding powder from 110 to 150 °C. The rate was found to be dependent on both the chemical kinetics and the mass transfer resistance. Since the HMX particles are nonporous and external mass transfer dominates, gas−liquid film theory for fast chemical kinetics was used to model the reaction rate.

Aqueous solubility and alkaline hydrolysis of the novel high explosive hexanitrohexaazaisowurtzitane (CL-20)

“…The by-products resulting from the alkaline hydrolysis of energetic materials could possibly be disposed of directly [8] or can be further treated biologically [10]. Several researchers have investigated the kinetics of the alkaline hydrolysis of nitrated energetic compounds such as RDX, HMX, TNT and nitrocellulose [11][12][13][14][15][16][17]. To date there have been no studies on the kinetics of the alkaline hydrolysis of CL-20.…”

The use of ultra high-performance liquid chromatography for studying hydrolysis kinetics of CL-20 and related energetic compounds

“…end-products and by-products. At elevated pH, the formaldehyde is subject to a Canizarro reaction [28] and produces formate [21]. They also established that reaction is second-order with respect to RDX and OH − reaction components.…”

“…The kinetics of the alkaline hydrolysis of energetic compounds has been studied previously [3,4,[15][16][17][18][19][20][21][22][23][24][25][26][27]. Hoffsommer et al [17] identified end-products and a rate-determining E2-elimination mechanism as the initial step of the alkaline hydrolysis of RDX.…”

In Silico Alkaline Hydrolysis of Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine: Density Functional Theory Investigation

“…Several other treatment processes, which are alternatives to the traditional method of explosive destruction, open burn/open detonation, have been evaluated on laboratory or pilot-plant scales for removal of HMX. These processes included biodegradation, phytoremediation, chemical oxidation, , reduction by zerovalent iron, , adsorption, and base hydrolysis. − Alkaline hydrolysis (at pH > 10) is one of the most promising methods for HMX remediation since it is easy to implement and control, and this process decomposes HMX into organic and inorganic salts, soluble organic compounds, and benign nitrogen gases. − Base hydrolysis of HMX is exothermic. The heat of reaction, calculated from differential scanning calorimetry of NaOH hydrolysis of HMX dissolved in dimethyl sulfoxide (DMSO) at room temperature, was found to be about 2.3 kJ/g (162.72 kcal/mol) for HMX .…”

“…The heat of reaction, calculated from differential scanning calorimetry of NaOH hydrolysis of HMX dissolved in dimethyl sulfoxide (DMSO) at room temperature, was found to be about 2.3 kJ/g (162.72 kcal/mol) for HMX . Kinetics for aqueous alkaline hydrolysis of HMX and temperature dependence of the rate constants were investigated by various groups. − Experimental data indicate that HMX decomposition is a highly multistep chemical process that in the initial steps follows a second-order rate equation and is first-order in aqueous HMX concentration and first-order in base concentration. ,− Rate enhancement for HMX hydrolysis was observed for the cationic surfactant ethylhexadecyldimethylammonia bromide . The efficacy of alkaline hydrolysis may be enhanced with an increased reaction temperature. − , Reported second-order rate constants at different temperatures cover a wide range, from 1.8 × 10 –2 M –1 ·min –1 at 25 °C to 0.47 M –1 ·min –1 at 50 °C (see Table S1 in Supporting Information for details) .…”