Permeation of supercritical carbon dioxide through polymeric hollow fiber membranes

Permeation of carbon dioxide was measured for two types of composite polymeric hollow fiber membranes for feed pressures up to 18 MPa at a temp. of 313 K. support membrane. The membranes consist of a polyamide copolymer (IPC) layer or a poly(vinyl alc.) (PVA) layer on top of a polyethersulfone (PES). For both membranes, the carbon dioxide permeance has a max. as a function of the feed pressure at about 8 MPa. A good description of the max. in the carbon dioxide permeance is possible with a model based on the ratio of the d. to viscosity. A comparison with permeation results for nitrogen for feed pressures up to 16 MPa, supports the findings that viscous flow is the main mechanism for mass transport across the membranes. Both membranes show an increase in the carbon dioxide permeance as a function of the exposure time to supercrit. carbon dioxide. Crosslinking of the IPC layer resulted in a stable IPC-based membrane at the cost of a small redn. in permeation of carbon dioxide. [on SciFinder (R)]