Analysis of black powder

The thermal analysis of black powders used for different purposes and containing differing proportions of ingredients can give an indication of the system stoichiometry by virtue of the rate and magnitude of measured exothermic events. 

References on Examination of Dynamites and of Other Blasting Explosives (practiced in USA) 1) W.O. Snelling C.G. Storm, The Analysis of Black Powder and Dynamite , USBurMines Bull 51(1916) 2) C.G. Storm, The Analysis... 

If desired, the approach above may be adapted to semiquantitative analysis of black powder, Pyrodex, or flash powders. A weighed sample, 0.25 g or more, on a tared filter paper is treated several times with a few milliliters of hot water, the filter dried, and the weight loss determined. The loss represents the oxidizer concentration. The filter is treated with pyridine, dried, and reweighed. The weight loss represents sulfur concentration and the residue either charcoal or aluminum as appropriate. 

FIGURE 20.16 Two-dimensional ion mobility-mass spectra of black powder with mass spectra (top) from 10 to 200 Th and mobility spectra (right) with a drift time range of 6000 is (6 ms)—12,000 ps (12 ms). Source Crawford, C.L., et al. (2010) Analysis of black powder by ion mobility-time-of-flight mass spectrometry. Analytical Chemistry, 82(1), 387-393. 

Crawford, C.L., et al. (2010) Analysis of black powder by ion mobihty-time-of-flight mass spectrometry. Analytical Chemistry, 82, 387-393. 

Analysis of the combustion products of a particular brand of black powder gave the following results56 42.98% of its weight as gases, 55.19% solids, and 1.11% water. Analysis of the solid products (percent by weight) and of the gaseous products (percent by volume) is as follows ... 

In previous casework in which the majority of the FDR particles contained potassium and sulfur, frequently at high levels, it was thought that the ammunition responsible probably contained black powder. In most of the cases the type of ammunition was not known, whereas in others the sampling and analysis of the residue from the interior of the spent cartridge cases confirmed the presence of black powder. 

Near-IR spectroscopy proved valuable for the analysis of pharmaceutical powders in a 1981 paper by Becconsall et al. [73]. Near-IR and UV photoacoustic spectroscopy were used for determination of propranolol (PR)/magnesium carbonate mixtures. Spectra were collected from 1300 to 2600 nm with carbon black as the reference. An aromatic C-H combination band at 2200 nm and an overtone band at 1720 nm were used to quantify PR. In this case, the UV data were nonlinear, while the NIR method provided a linear calibration. 

While IMS and MS are both widely used for explosives analysis, hybrid IM-MS instruments have recently been applied to detect explosives [186]. The lack of HLS-related research with IM-MS systems may be in part due to the availability of commercial IM-MS systems [183,187]. However, this hybrid technique offers a distinct advantage over both IMS and MS alone the ability to simultaneously separate samples by both mobility and mass. This twofold separation mechanism greatly decreases the likelihood of a mass or mobility interfer-ent masking the signal of the analyte of interest. In complex, real-world samples where matrix effects may significantly inhibit the detection of trace amounts of explosive material, the ability to separate in two dimensions (2D) is extremely powerful [188]. Figure 20.16 shows a typical 2D IM-MS plot of black powder with... 

For the catalyst preparation REACHIM vanadium pentoxide, pure for analysis, and POCH antimony trioxide, of the same grade of purity, were used. The grounded mixture of vanadia and antimony trloxide in quartz ampoule sealed without any evacuation was placed in a cool oven, then it was heated slowly up to 973 K for 7 hours, annealed at this temperature for 30 hours and slowly cooled down to room temperature for 10 hours. One part of black powder obtained by this procedure was xidized at 673 K in air atmosphere for 30 hours another onewas reduced at the same temperature in vacuum (10 Torr) for 4 hours. 

D. R. Mouta and co-workeis, Mayards Analysis of the Final Design of the Improved Black Powder Process, Vols. 1—2, Rpt. J6329, Illinois Institute of Technology, Chicago, 1963. 

Occasionally a colorless solution was obtained at approximately — 50°. In most eases the reaction mixture contained a small quantity of fine suspended black powder (presumably copper metal). Examination of the reaction mixture at this stage by hydrolysis of a sample at —35° and gas chromatographic analysis demonstrated the presence of approximately 10% of 2,4-hexadienes [predominantly the (E),(E)-isomer],... 

An alternative mode for dehydrobenzoannulene decomposition was recently reported by Vollhardt et al. [58]. Non-planar hybrid 81, prepared in low yield via cyclodimerization of known triyne 82 [Eq.(3)], reacted explosively at ca. 250°C to give a nearly pure carbon residue. Solvent extraction of the black powder failed to yield soluble materials such as fullerenes however, analysis of the residue by TEM showed formation of bucky onions and bucky tubes [59], in addition... 

For onsite analysis, the examination of the vast number of samples necessitates the use of quick, reliable, field portable equipment that can rapidly, quantitatively verify the many chemically different types of ammunition, explosives, and pyrotechnics. The most common suite of analytes to detect is large, consisting of very chemically different compounds and usually occurs at trace levels in complex environmental matrices. This suite encompasses smokeless powders, black powders, and numerous propellant and energetic formulations. Detection should also be sought for common decomposition products of these explosives such as the methylanalines, aminonitrotoluenes, nitrotoluenes, mono- and dinitoroglycerines, and the nitrobenzenes under on-site conditions. 

Thermal analytical techniques such as thermogravimetry (TG), differential thermal analysis (DTA) and differential scanning calorimetry (DSC) have all been successfully employed in studying the pyrotechnic reactions of energetic materials such as black powder, as well as of binary mixtures of the constituents. 

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