Prospective Symbiosis of Green Chemistry and Energetic Materials

Abstract

A global increase in environmental pollution demands the development of new "cleaner" chemical processes. Among urgent improvements, the replacement of traditional hydrocarbon-derived toxic organic solvents with neoteric solvents less harmful for the environment is one of the most vital issues. As a result of the favorable combination of their unique properties, ionic liquids (ILs), dense gases, and supercritical fluids (SCFs) have gained considerable attention as suitable green chemistry media for the preparation and modification of important chemical compounds and materials. In particular, they have a significant potential in a specific and very important area of research associated with the manufacture and processing of high-energy materials (HEMs). These large-scale manufacturing processes, in which hazardous chemicals and extreme conditions are used, produce a huge amount of hard-to-dispose-of waste. Furthermore, they are risky to staff, and any improvements that would reduce the fire and explosion risks of the corresponding processes are highly desirable. In this Review, useful applications of almost nonflammable ILs, dense gases, and SCFs (first of all, CO ) for nitration and other reactions used for manufacturing HEMs are considered. Recent advances in the field of energetic (oxygen-balanced and hypergolic) ILs are summarized. Significant attention is paid to the SCF-based micronization techniques, which improve the energetic performance of HEMs through an efficient control of the morphology and particle size distribution of the HEM fine particles, and to useful applications of SCFs in HEM processing that makes them less hazardous.

Assembly of Tetrazolylfuroxan Organic Salts: Multipurpose Green Energetic Materials with High Enthalpies of Formation and Excellent Detonation Performance

“…The colorless single crystals of 8·H 2 Ow ere grown from water.A t 120 Kc rystals of 8·H 2 O( C 6 H 9 N 17 O 3 )a re triclinic;s pace group P1; a = 7.4669(5), b = 8.7018 (6), c = 11.7937(8) ; a = 72.9416 (12), b = 79.0760 (12), g = 87.7424(13) 8; V = 719.21(8) 3 ; Z = 2; 1 calcd = 1.696 gcm À3 ;F (000) = 376. Intensities of 14 395 reflections were measured with aB ruker APEX2 Duo CCD diffractometer[ l(Mo Ka ) = 0.71073 , w-scans, 2q < 608]a nd 4201 independent reflections [R int = 0.0196] were used for further refinement.…”

“…Moreover, the formation of energetic salts is a useful strategy to enhance the stability of a molecule without negatively impacting the performance. Such advantages enable a variety of applications for these green energetic organic compounds including explosives, propellants, or pyrotechnics …”

“…Such advantages enable av ariety of applications for these green energetic or-ganic compounds including explosives, propellants, or pyrotechnics. [6] Ac ommons ynthetic route for the design of energetic nitrogen-rich compounds involves the incorporation of af ive-membered azole moiety.R ecently,p romisingr esults in the design of new explosives were obtained in pyrazole, [7] triazole, [8] 1,2,4oxadiazole, [9] and 1,2,5-oxadiazole (furazan) [10] series. However, the highest enthalpies of formation in nitrogen and nitrogenÀ oxygen azole series correspond to the tetrazole and 1,2,5-oxadiazole 2-oxide (furoxan) rings (according to our recalculated values, Figure 1).…”

The Mechanism of Low-Temperature Oxidation of Carbon Monoxide by Oxygen over the PdCl2–CuCl2/γ-Al2O3 Nanocatalyst

“…Of particular attention are the hybrid organic–inorganic materials that promise an advantageous combination of structural and porous characteristics [37,38,39,40]. …”

Investigation on Stripping-down TNT from Waste Munitions by Supercritical CO2 Fluid Extraction under Low Temperature Conditions

“…The supercritical fluid extraction technique using carbon dioxide (CO 2 ) has been recognized as a green technology, which has also been a rapidly developing technique for the chemical industry in recent years [6,7]. CO 2 is a clean and versatile solvent with gas-like diffusivity and liquid-like density in the supercritical phase, which has provided an excellent alternative to the use of chemical solvents.…”