采用加热解吸结合催化氧化及吸附法对含氚硅胶中的氚回收率进行了精确量化.结果显示,含氚硅胶中的氚主要以化合态的形式存在,含氚硅胶中氚回收率随样品的加热解吸温度的升高而增加,在相同的解吸温度下,含氚硅胶中氚回收率随载气流速的增加而呈下降趋势,在解吸温度为500℃及载气流速为60 mL/min下仍有5%以下的氚滞留在硅胶中,且该方法的不确定度为0.55%.%The tritium recovery from tritium-containing silica gel samples was measured by thermal desorption of tritium from silica gel, followed by ethylene glycol absorption to dissolve the released tritium oxides, and by catalytic oxidation to convert any elemental tritium to tritium oxides. The results show that tritium oxides are the predominant chemical state for tritium in silica gel. The tritium recovery is increased as the thermal desorption temperature increases, but is decreased as the carrier gas flow increases for a given desorption temperature. As much as 5％ of tritium is retained in the silica gel after thermal desorption at 500℃ and scavenged by H2 at 60 mL/min. The uncertainty of this method is estimated to be 0.55％.
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