FILTRATION MEMBRANE WITH TUBULAR SUPPORT

摘要

A membrane generally comprises a tubular support, and a polymeric membrane film on the support. The polymeric membrane film comprises three zones cast simultaneously from a single dope. The three zones include an inner zone on the support comprising macro-void pores, an intermediate zone on the inner zone comprising macro-void pores smaller than the macro-void pores of the inner zone, and a skin on the intermediate zone comprising pores of less than 1 micron.