Desublimation of two-component vapors on the surface of an annular-tube cold trap.

Abstract

Numerical analyses were carried out on the desublimation rate of two component vapors from a gaseous mixture including a noncondensable gas in an annular cold trap, assuming that two vapors formed a compact solid phase and were insoluble in the solid state. It was predicted that there were two different patterns on the distribution of the mass fraction in the solid phase, where one showed a continuous change and another had a maximum or a minimum. The experimental studies were made using benzene and p-xylene as vapors. As the p-xylene mass fraction in the solid phase increased, the solid phase varied from a compact form to a frosty form, and consequently its apparent density decreased. The experimental results were in very good agreement with the calculated results on the thickness, and also fairly good on the distribution of mass fraction in the solid phase.