PREPARATION OF HOLLOW FIBER MEMBRANES FROM POLYETHERIMIDE FOR GAS SEPARATION

The objective of this work was to develope integral asymmetric polyethermide hollow fiber membranes both with a microporous skin and with a dense skin on the bore side of the fibers. The microporous types would to be suitable as substrate membranes for the preparation of composite membranes. The effect of the composition of the polymer solution, the spinning conditions and the post-treatment on the porosity of the skin and on the shape and morphology of the fiber wall was investigated. Silicone composite membranes with an oxygen permeability of up to 5.3 x 10(-9) m3 (N)/m2-sec-Pa and dense membranes with a helium/nitrogen selectivity of about 1.70, at a helium permeability up to 5.6 x 10(-10) m3 (N)/m2-sec-Pa, were obtained.