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Published on: September 25, 2017
Urea nitrate, an exceptionally easy-to-make improvised explosive: studies towards trace characterization
Tsippy Tamiri1, Rinat Rozin, Nitay Lemberger
1Division of Identification and Forensic Science, Israel Police National HQ, Jerusalem, 91906, Israel.
Analytical and Bioanalytical Chemistry
|July 4, 2009
Summary
Identifying urea nitrate in post-blast debris is challenging due to its decomposition. This study developed methods using Crown ethers for effective extraction and characterization of urea nitrate traces.
Area of Science:
- Forensic Chemistry
- Explosives Analysis
- Analytical Chemistry
Background:
- Urea nitrate is a potent improvised explosive used in terrorism and historical attacks.
- Identifying urea nitrate in post-blast debris is difficult due to its instability and decomposition into urea and nitric acid.
- Decomposition products can be mistaken for other substances like ammonium nitrate.
Purpose of the Study:
- To develop a reliable method for identifying urea nitrate in post-blast traces.
- To overcome challenges associated with urea nitrate's instability and decomposition.
- To improve the detection of urea nitrate in forensic investigations.
Main Methods:
- Development of a spectrophotometric technique for quantitative urea nitrate determination.
- Optimization of extraction and separation conditions to minimize decomposition.
- Utilizing Crown ethers as host compounds for extracting urea nitrate into organic solvents.
- Characterization of extracted adducts using microanalysis and spectroscopic techniques.
Main Results:
- A spectrophotometric method was established for quantitative analysis.
- Conditions were identified for minimal decomposition during extraction and separation.
- Crown ethers facilitated the extraction of urea nitrate into organic solvents, forming stable adducts.
- Only one sample out of 28 yielded a typical adduct ion via liquid chromatography/mass spectrometry.
Conclusions:
- Urea nitrate identification in post-blast debris remains a significant challenge.
- Crown ether-mediated extraction offers a promising approach for isolating and characterizing urea nitrate.
- Further research is needed to enhance detection sensitivity and reliability in forensic applications.
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