Seeking forensic evidence of preparation routes to 2,4,6-trinitrophenol

The explosive 2,4,6-trinitrophenol (picric acid) was prepared by five different methods using laboratory-grade chemicals as well as consumer-available chemicals in order to establish background forensic information. Nitrate sources were altered by using three concentrations of nitric acid or nitrate salts; an over-the-counter source of sulfuric acid was also investigated. Recovered products were identified using spectroscopic and thermal techniques. Impurities caused by over-the-counter starting materials were carried throughout the synthesis process to the crude recovered products and were detected by infrared and Raman spectroscopy and differential scanning calorimetry. In cases where nitrate salts were used; potassium picrate was recovered.