Comparison of Smokeless Powders and Mixtures by Capillary Zone Electrophoresis

• NCJ Number: 209092
• Journal: Journal of Forensic Sciences Volume: 50 Issue: 2 Dated: March 2005 Pages: 307-315
• Author(s): Kristy G. Hopper B.S.; Bruce R. McCord Ph.D.
• Date Published: March 2005
• Length: 9 pages
• Publication Format: Article
• Publication Type: Report (Study/Research)
• Language: English
• Country: United States of America
• Note: Portions of this paper were presented at the 54th Annual Meeting of the American Academy of Forensic Sciences in Atlanta, GA, and the 2003 Mid-Atlantic Association of Forensic Science Annual Meeting in Annapolis, MD.

Annotation

This study analyzed a variety of smokeless powders to determine differences in ionic composition.

Abstract

Smokeless powders consist of a variety of organic constituents, and the focus of most analyses have involved the identification of these compounds; however, these compounds also produce small amounts of inorganic salts on deflagration. Inorganic salts result from the additives and decomposition products of various components in smokeless powders and may be significant in characterization. In the current study, the components analyzed included ions formed during powder production and those formed following deflagration. The experiments performed assessed the difference between residue from unburned and burned powders, determined the composition of the residue produced when a smokeless powder was combined with a muzzleloading powder, and evaluated the various ion products and concentrations between laboratory and field deflagrated samples. The paper's description of the materials and methods used encompasses capillary zone electrophoresis (CZE), ion chromatography (IC), CZE analysis, and IC analysis. The description of samples and preparation addresses the smokeless powders, the smokeless powder preparation, and the pipe bomb study that was conducted to compare differences between the deflagration of individual powders within a device and those powders that were openly burned within the laboratory. The results show that ionic profiles can be used to characterize smokeless powders. The analysis also included a smokeless powder/Pyrodex combination to determine whether smokeless powder ions are distinguishable in a mixture; the high concentration of ions present in Pyrodex RS prevented its detection. In addition, 5 different smokeless powder samples as well as Pyrodex RS were collected for analysis subsequent to deflagration in 15 plastic pipe bombs. The authors advise that the relative ion concentrations between these powders can be used to illustrate the differences between open burning and pipe bomb deflagration. 11 figures, 2 tables, and 21 references