Gas chromatographic measurement of low specific surface area by dynamic adsorption of krypton at low temperature

Krypton was used as adsorbent to measure low specific surface area by dynamic adsorption at low temperature. The results showed that: when the volume of the sample tube is less than 15cm~3, the effect of thermal diffusion can be neglected in the range of BET relative pressure. When the total surface area of the sample is less than 0.5m~2, it takes twenty minutes to reach adsorption equilibrium. The peak shape would take the form of Garssion distribution curve, and abnormal signals would not occur for the samples having 0.05 to 5m~2/g specific surface area, Experimental, data perfectly fit the BET equation.