Combustion analysis (melt extraction) allows to determine the bulk concentration of C, S, N, O and H is solid samples. Small chips of a solid sample are combusted. The reaction gases are detected by infrared absorption detectors for C, S an O and by thermal conductivity detectors for N and H.
OCAS furthermore, has equipment for hot extraction. In this case larger samples are heated in an external furnace, allowing to determine diffusible hydrogen or surface carbon. The external furnace can be heated up to approximately 900°C.
1-5 ppm range for C, S
0.1 ppm O, N
0.01 ppm for H