Forensic Chemical Study on Cotton by Acid-Catalyzed Pyrolysis-Gas Chromatography

Abstract

It is known that the major products in the pyrolysis of cellulose can not be detected by gas chromatography because of their low volatility. Hence it has been difficult to analyze a slight amount of cotton composed of cellulose by pyrolysis-gas chromatography (PyGC).In our study, acid-catalyzed pyrolysis was applied to forensic discrimination of cotton and its blended yarn by PyGC. Fibers were pyrolyzed using a Curie-point pyrolyzer, attached to gas chromatograph or gas chromatograph-mass spectrometer under the conditions by the addition of hydrochloric acid or phosphoric acid. The presence of acid during pyrolysis provided an increase of volatile products such as furfural, and elevated detection limit of the fibers by PyGC in comparison with the conventional methods. When 10% of hydrochloric acid or 20% of phosphoric acid was added, more furfural was detected. This method made it possible to analyze a slight amount of cotton and its blended yarn by PyGC. © 1993, The Pharmaceutical Society of Japan. All rights reserved.