Using Alkylate Components for Classifying Gasoline in Fire Debris Samples

Abstract

The characteristic that discriminates gasoline from other ignitable liquids is that it contains high-octane blending components. This study elaborates on the idea that the presence of gasoline in fire debris samples should be based on the detection of known high-octane blending components. The potential of the high-octane blending component alkylate as a characteristic feature for gasoline detection and identification in fire debris samples is explored. We have devised characteristic features for the detection of alkylate and verified the presence of alkylate in a large collection of gasoline samples from petrol stations in the Netherlands. Alkylate was detected in the vast majority of the samples. It is demonstrated that alkylate can be detected in fire debris samples that contain traces of gasoline by means of routine GC-MS methods. Detection of alkylate, alongside other gasoline blend components, results in a more solid foundation for gasoline detection and identification in fire debris samples.

Artificial intelligence and thermodynamics help solving arson cases

“…Generation of gasoline data for the simulations. Details of collecting gasoline reference samples are provided by Peschier et al 27 . The gasoline samples were collected in the period of May-August 2011 from 230 different petrol stations in the Netherlands.…”

Detection and Characterization of Ignitable Liquid Residues in Forensic Fire Debris Samples by Comprehensive Two-Dimensional Gas Chromatography

“…In this study within-class differences were observed for all three IL types but differences were most pronounced for gasoline. Various approaches to distinguish gasoline samples are described in literature, such as (i) substituted naphthalenes [7,32]; (ii) alkylate compounds [9]; and (iii) octane rating [33]. Figure 6 shows an example of two different gasoline batches and the variation observed.…”

“…Fire debris analysis is a complex and challenging task due to several interfering factors, such as (i) substrate variability and released pyrolysis products that are also commonly found in ignitable liquids (IL); (ii) the complex chemical composition of different types of ignitable liquid; (iii) evaporation and consumption of the ignitable liquid during a fire; and (iv) (bio)-degradation of fire debris samples. Several studies have been conducted based on classification and within-class differentiation with the use of neat ignitable liquids in order to improve the detection and classification of ILRs in fire debris samples [6][7][8][9]. An overview of challenges in terms of the variety of ignitable liquids, classification and matrix interferences in fire debris analysis has been provided by Baerncopf et al [10].…”