NORA Manufacturing Sector Strategic Goals
927ZJEXa - Explosivity and Flammability of Carbon Nanotubes (NTRC)Start Date: 10/1/2009
End Date: 9/30/2013
Principal Investigator (PI)Name: Leonid Turkevich
Funded By: NIOSH
Primary Goals Addressed10.0 , 9.0
Secondary Goal AddressedNone
Attributed to Manufacturing100%
NIOSH is undertaking an initial assessment of the explosion hazards of carbonaceous nanoparticles—in particular, carbon nanotubes. Explosive dust clouds can be generated from most organic materials. Dust explosions involving 100–102 ?m particles have been extensively studied. Ignition sensitivity and explosion violence of a dust cloud depend strongly on the particle size, primarily via specific surface area. The violence of the dust explosion and the ease of ignition generally increase as the particle size decreases. Particle explosive characteristics for carbon nanotubes will be related to material oxidation parameters.
This project will measure explosion parameters of several identified carbon nanomaterials: carbon nanofibers (CNFs), multiwalled carbon nanotubes (MWCNTs), single-walled carbon nanotubes (SWCNTs). Such measurements have not been previously made. Explosion experiments will be carried out at PRL in a 20L chamber that has been utilized extensively to characterize the explosion characteristics of coal dust. These explosion parameter measurements will be benchmarked against other carbon particulate systems (e.g. carbon black) and correlated with specific surface area. Parameters to be measured include MIE, LEL, maximum explosion pressure (Pmax), violence explosion index (Kst = dP/dt V1/3). In parallel, we will monitor the flammability and onset of combustion of these materials via controlled atmosphere temperature studies at DART. Such studies have been useful in characterizing diesel particulates.
Literature citations of the publications produced by this project will substantiate the project's usefulness to the scientific community. Application of the research findings by other government agencies will be substantiated by discussion of the results in policy documents. Explosivity hazards discovered by this project will be communicated to material vendors and to external testing laboratories.
Under certain conditions, engineered nanomaterials may pose a dust explosion hazard and spontaneously ignite when exposed to air, due to their large surface area. Little is known about the dust explosion hazard for the general class of nanoparticles (carbon, metal and metal oxide).