天然ゼオライトによる水素の分離

Abstract

Permeation of hydrogen through natural zeolite was studied to obtain the fundamental data for the separation of hydrogen. The following results are obtained.The membrane made of natural zeolite, which is yieled from Itaya of Yonezawa city of Yamagata prefecture, has the excellent heat-resistance and the complicated porous structure like a maze. The pore sizes of the membrane are found to be distributed from 80 to 10, 000 Å. It is also found that Itaya natural zeolite has many suitable pore sizes from 80 to 300 Å for the separation of hydrogen by Knudsen flow.The rate of gas permeation increased as the operational pressure difference increased. The separation factor of hydrogen is affected by the ratio of the pressure of permeated gas P2 to the pressure of feed gas P1, and increases with an increase in the pressure difference. The pressure reduction of permeated gas was found to be very effective to increase the hydrogen separation factor of the membrane. It was also found that the rate of gas permeation was reduced in some degree as the operational temperature increased up to 523K, but that the separation of hydrogen by the membrane was improved.These experimental results mentioned above reveal that Itaya natural zeolite can be utilized for the hydrogen separation from gas mixture under the wide range of opertional conditions of temperature and pressure.