Characterization of ED-XRF technology applied to wooden matrix

The Energy Dispersive X-ray (ED-XRF) Fluorescence is an analyticals technique for detection and quantification of heavy metals, widely used in portable devices basically conceived for metallic alloys. Preliminary tests are needed to use the instrument on different matrices like wood. In this work minimum detection limit (MDL), signal to noise ratio (SNR), repeatability, relationship between measurement time and elements detected, depth of measurement, set-up (background, operator ergonomics and operator X-ray adsorbed dose) have been investigated or tested. MDL varies with time ranging from few thousands (e.g. Cl) to few units (e.g. As) of mg.kg-1. Repeatability error is 5-6 %. Average SNR ranges from 5 to 31 in function of measurement time. The measurement time influences detection of elements. Measurement depth ranges from 15 to 24 mm according to wood density and anatomy. Best backgrounds are air and shield cap. Best set-up is inside X-ray protection cabinet. Radiation leakages have been found in bench top operations. Effectiveness of technique has been proven, with limitations, in multielement analysis of wood-based products.