Application prospects of dense gas separation hollow fibers based on poly(4-methyl-1-pentene)

The paper presents the new data of gas transfer characteristics of semicrystalline poly(4-methyl-1-pentene) (PMP) as for films as for hollow fibers (HFs) with dense selective layer. The experimental data obtained earlier made it possible to calculate the gas transport characteristics of the amorphous and crystalline phases of PMP for some gases at temperature from 10 to 80 °C (below and above Tg). On the basis of these data and using the correlation approach, an assessment of the expected gas transport characteristics of HFs based on PMP was carried out in this work for helium and lower hydrocarbons, as well as for water vapors. It is shown that crystalline phase is very permeable and higher crystallinity degree leads to the increasing of PMP selectivity. Laboratory-scale membrane module with commercial hollow fibers of PMP was prepared and successfully tested by the differential method of gas permeability. Application of crazing method which should increase the crystallinity degree of PMP seems promising for the production of perspective HFs with improved transport and separation performance compared with the existing ones.