Experimental characterization of the combustion of single lithium particles with CO2

Abstract

Combustion and temperature measurement of single lithium particles (dp<250μm) with CO2 was carried out in a laminar flow reactor. An imaging two-color pyrometer system was used to measure particle and flame size as well as combustion temperatures. The results indicate two different combustion phenomena, which have been identified in literature before: Gas-phase reaction at temperatures above 2500K and surface reaction of lithium with CO2 at temperatures between 1500 and 1800K. In addition, a sampling probe was utilized to extract burning particles from the reactor. The extracted probes were analyzed concerning their constituents using X-ray diffraction analysis and their shape and surface with scanning electron microscopy. The results showed lithium carbonate as main reaction product and a relatively smooth surface of the particles after burn-out. Combining the experimental findings, a single particle combustion model was suggested and apparent reaction kinetics was determined.