For the detection of possibly increased concentrations of airborne nanofibers at workplaces handling such materials, it is necessary to know the background concentration of nanoscale fibers in the environment. Possible emission sources of carbon nanofibers are combustion processes. The project develops methods for collecting, purifying and analyzing exhaust gas samples, with the aim of investigating and optimizing the distinguishability and separate quantifiability of soot particles and carbon nanofibers. Exhaust gas samples are expected to contain predominantly soot particles and only a few carbon nanofibers. For this reason, oxidation processes for the selective removal of soot-like carbon structures are tested. They are supplemented by spectroscopic methods, from which additional information on a fiber identity is expected if morphological electron microscopic analyzes fail for samples that are particle-dominated.
Unit 4.5 "Particulate Hazardous Substances, Advanced Materials"