Ultrahigh Flux Composite Hollow Fiber Membrane via Highly Crosslinked PDMS for Recovery of Hydrocarbons: Propane and Propene.

In order to make membrane separation technologies more cost-competitive with the well-established processes that are energy intensive for gas/vapor separation, a defect-free membrane with a high gas permeance is necessary. However, it remains challenging to meet these needs because of the difficulties in developing a suitable material and process that are economical and practical. Herein, a novel and straightforward strategy is presented to produce a defect-free hollow fiber composite membrane using a highly crosslinked polydimethylsiloxane (PDMS) synthesized by using a postcrosslinking method. The PDMS can be directly coated on a polyacrylonitrile (PAN) membrane substrate, and the resultant PDMS/PAN composite membrane has ultrahigh C3 H8 and C3 H6 permeances that are higher than 10 000 and 11 000 GPU, respectively, and the corresponding permselectivity of C3 H8 /N2 and C3 H6 /N2 are about 21 and 24, respectively. The newly developed methods and materials may open up a new cost-effective method to fabricate next-generation composite membranes for the recovery of hydrocarbons, organic vapors, and gases.