Measurements of plasma temperatures in H/sub 2//carbon/AR microwave plasma by UV emission spectroscopy

Summary form only given. We have developed a microwave plasma at atmospheric pressure in the mixtures of hydrogen, carbon, and argon in order to study the hydrogasification reaction of coal. A coal gasification is a newly highlighted research field because coal is abundant energy source for methane or hydrogen. However, the coal gasification process has encountered technical barriers because no reliable sulfur-tolerant chemical catalysts exist. Los Alamos National Laboratory has proposed a plasma catalyzed coal gasification concept, where plasma turns coal and reactant gases into highly reactive free radicals and excited species, which are believed to promote gasification reactions. Preliminary results showed that small amounts of CH₄ , C₂H₂, and C₂H₄ are detected through the hydrogasification reaction. One of issues to be investigated is how a non-equilibrium property of the microwave plasma affects gasification reactions of coal. The excitation and rotational temperatures are obtained with measuring an Ar and C₂ emission lines, respectively. Hydrogen atoms will be measured with NO ₂ titration techniques. In this presentation, we will emphasize the mechanism of coal hydrogasification with characterizing the plasma properties and correlating these to hydrogasification reactivity