냉동증류법을 이용하여 C8-방향족화합물의 여러 혼합물로부터 고순도의 P-크실렌을 분리하였다. 냉동증류의 과정 중 액상혼합물이 결정화되는 성분의 어느 점 이하로 과냉각되는 현상이 관찰되었으며 원료중의 p-크실렌 함량이 적을수록 수율이 감소하는 경향을 보였다. 그러나, 원료 중의 p-크시렌의 함량에 따른 제한이 있었으며 그 이하의 함량에서도 고순도 분리가 이루어지기 위하여서는 완전한 단열조건이 필요함을 알았다.
Super-pure p-xylene was obtained from the various combinations of C8-aromatics by the distillative freezing method. The super-cooling effect was observed during distillative freezing operation. As the concentration of impurities in feed increased, the yield of product decreased. However, it was found that the concentration of p-xylene at feed composition was limited to get super-pure p-xylene. And adiabatic conditions during experiment should be con-sidered as a great importance through distillative freezing operation.
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