Mass spectrometric determination of gases in individual coated HTR fuel particles. I

A method is described which allows the simultaneous determination of fission and reaction gases in individual coated particles at temperatures up to 2 0000C. The particles are heated under high-vacuum in a micro resistance-furnace up to the desired temperature. After preselected times the particles are crushed by action of a pneumatic cylinder. The gases liberated are fed into a quadrupole analyzer where they are analyzed in a dynamic mode. A peak selector allows the simultaneous measurement of up to four gases. The method is used routinely for the determination of fission gases (Kr and Xe) and of carbon monoxide which is formed as a reaction gas from oxide fuel. Precision and accuracy are in the order of a few percent. Detection limits for routine measurements are about 10-7 cm3 (STP) for Kr and Xe and 2x10-5 cm3 (STP) for CO but can be lowered by special techniques. (Auth.)