Application of gas chromatography - field asymmetric ion mobility spectrometry (GC-FAIMS) for the detection of organic preservatives in wood

Abstract

The purpose of the investigations reported was a feasibility study of field asymmetric ion mobility spectrometry (FAIMS) applications for the characterization of recovered wood. Especially the treatment with organic wood preservatives represented by their active substances should be detected in concentrations commonly used for timber products. The following pesticides were determined: PCP, lindane, dichlofluanide, tolylfluanide, propiconazole, tebuconazole, IPBC (iodine-propyl-butyl-carbamate), K-HDO ((N-Cyclohexyl-diazeniumdioxy)-potassium) and fenoxycarb. The first step was to show that such compounds can be vaporized under moderate conditions. Solid-phase microextraction (SPME) was capable for sampling and enrichment. The reference analytics was made by gas chromatography coupled with mass spectrometry (GC-MS). Both, waste wood, in this case window frames from reconstruction work, and self-prepared doped wood samples were utilized. For analyzing the complex mixture of vaporized native and artificial ingredients of the lignocellulose material a chromatographic pre-separation was necessary. Hence, the second step was to study the behavior of active substances in the analysis with GC-FAIMS to clarify which peaks in positive and negative mode are dedicated to wood preservatives. At least one strong signal from every selected active compound was located for clear identification. With that knowledge, FAIMS was successfully applied for the distinction of natural and treated wood samples. The discrimination can be a basis for industrial sorting plants which could help to increase the contemporary amount of material usage of recovered wood for a more ecological and economical handling of natural resources.