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Removal of Nitramine Explosives in Aqueous Solution by UV-Mediated Advanced Oxidation Process in Near-Neutral Conditions

Khue Do Ngoc, Bach Vu Quang, Binh Nguyen Thanh, Minh Do Binh, Nam Pham Thi, Loi Vu Duc, Nguyen Hoa Thanh

Journal of Ecological Engineering

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2021

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Vol. 22, nr 6

232--243

EN

Explosive compounds are hazardous to the environment, posing a serious risk to human and animal health and the ecosystem. The primary goal of research was to compare the efficiency of UV/H2O2, photo-Fenton, electro (EO)/ UV/H2O2 processes at near-neutral pH (pH=6) on the degradation of nitramine explosives (NAs), such as hexogen (RDX), octogen (HMX), and tetryl (TET), in an aqueous solution. The effect of operational conditions, likely pH of the solution, initial H2O2 concentration, initial Fe2+ concentration, and solution temperature, was observed. The removal kinetics fit with first-order kinetics and were in the order: photo-Fenton >EO/UV/ H2O2 > UV/ H2O2. The results showed higher rate constant values for TET, RDX and HMX removal by UV/ H2O2 (k = 0.07778, 0.03791 and 0.03786 min-1), EO/UV/ H2O2 (k = 0.16599, 0.1475 and 0.08674 min-1) and photo-Fenton (k = 0.18018, 0.1501 and 0.09336 min-1) processes. Furthermore, TET, RDX and HMX were mineralized at 59.7%, 45.1%, and 25.1 %, respectively, under optimum conditions after 60 min of the photo-Fenton process. From the economic perspective, photo-Fenton only requires 2.132–4.113 kWh m-3 to completely reduce NAs. Finally, acute toxicity towards Vibrio fischeri was defeated after usage of near-neutral photo-Fenton. Thus, photo-Fenton at circum-neutral is promising for low-cost, eco-friendly and efficient processes for treating nitramine explosives in aqueous solutions.

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Regularities of Spheroidization of HMX Extracted from Solid Propellant Disposal Products

Cheltonov Maksym, Zakusylo Roman, Ustymenko Ievhen

Central European Journal of Energetic Materials

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2020

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Vol. 17, no. 4

523--534

EN

Nitramines of high quality for manufacturing high-energy composites, such as oсtogen (HMX) and hexogen, have received much attention by researchers worldwide. Mixed formulations containing fillers in the form of spheroidal dispersed particles of explosives are homogenized at lower energy consumption. They are characterized by stable rheological characteristics, which guarantee the quality of the products obtained on the basis thereof. Methods for obtaining spherical nitramine particles by means of ultrasonic and hydromechanical rounding using commercial HMX were evaluated. It was found that under similar conditions, rounding by the hydromechanical process in a vortex device is more efficient and less energy-consuming than that of the ultrasonic method. It was confirmed that spheroidization of commercial HMX in an aqueous dimethyl sulfoxide (DMSO) medium by hydromechanical rounding occurs due to erosion of crystals of large size (70 μm or more). Based on the experimental results with spheroidization of commercial nitramine, the mass fraction content below 50 μm versus time was plotted for hydromechanical rounding. The method of hydromechanical rounding in aqueous DMSO to obtain spheroidized HMX, extracted from solid propellant using DMSO, was found to be the most suitable. Spheroidized modified HMX with specific characteristics (density and crystals of near-spherical shape) was obtained, which could be used for the manufacture of high-energy composites.

3

Metody otrzymywania oktogenu

Matys Z., Powała D., Orzechowski A., Maranda A.

Chemik

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2012

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Vol. 66, nr 1

58-63

PL

Omówiono metody otrzymywania oktogenu, nowoczesnego, termostabilnego kruszącego materiału wybuchowego. Przedstawiono dwie, opracowane w Instytucie Przemysłu Organicznego w Warszawie technologie otrzymywania tego związku. Metoda pierwsza polega na nitrowaniu mocznika mieszaniną nitrującą (kwas azotowy i oleum), a następnie cyklizacji dinitromocznika z urotropiną i amoniakiem do wytworzenia półproduktu - DPT, który następnie poddawany jest nitrolizie roztworem azotanu amonu w kwasie azotowym, która znalazła zastosowanie w praktyce przemysłowej. Druga metoda polega na nitrolizie urotropiny roztworem azotanem amonu w kwasie azotowym, w obecności kwasu octowego, bezwodnika kwasu octowego i trioksanu (trimeru formaldehydu).

EN

The paper describes the methods for manufacturing octogen, a modern, thermally stable, brisant explosive. Two production technologies for obtaining the compound developed at the Institute of Industrial Organic Chemistry have been presented. The first method uses the nitration of urea with a nitrating mixture (nitric acid and oleum), and the cyclisation of dinitrourea (DNU) with hexamethylenetetramine (HMTA) and ammonia to form a semi-product - DPT, which is then subject to nitrolysis after adding the solution of ammonia nitrate in nitric acid. This method has been implemented in industrial applications. The second method consists in the nitrolysis of hexamethylenetetramine (HMTA) with the solution of ammonium nitrate in nitric acid in the presence of acetic acid, acetic anhydride and trioxane (a trimer of formaldehyde).

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Electric Spark Sensitivity of Nitramines. Part II. A Problem of "Hot Spots"

Zeman S., Pelikán W., Majzlík J., Kočí J.

Central European Journal of Energetic Materials

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2006

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Vol. 3, nr 3

45-51

EN

Attention was focused on the influence of grain size upon the electric spark sensitivity of 1,3,5-trinitro-1,3,5-triazinane (hexogen) and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (octogen). Also the dependence of this sensitivity is monitored upon the addition of hard and fine admixtures (crushed glass or diamond dust) to these compounds and sample of ?-HNIW. It was found that this artificial introduction of the said admixtures decreases the electric spark sensitivity of corresponding mixtures because the number of intergrain contact points of the nitramines grains in the volume unit is decreased by implementation of the foreign particles. It was also suggested that dislocations in the crystals should play some role here. It is stated that an impact component absents in relevant electric discharge.

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Wytwarzanie oktogenu, własności użytkowe i zastosowanie

Chart Z., Chlebowski W., Mikulski T.

Problemy Techniki Uzbrojenia

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1999

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R. 28, z. 70

57--64

PL

W artykule przedstawiono nową metodę otrzymywania oktogenu, wyniki badań oktogenu krystalicznego oraz własności użytkowe oktogenu flegmatyzowanego woskiem i fluoropolimerami.