초록

The invention is a process for separating hydrogen from gas mixtures using a semi-permeable membrane consisting predominantly of polycarbonates derived from tetrahalobisphenols such as tetrabromobisphenol.

대표청구항 ▼

A process of separating hydrogen from gas mixtures comprising: (A) contacting one side of a semi-permeable membrane with a feed gas mixture containing hydrogen under pressure, wherein the membrane divides a separation chamber into a higher pressure side into which the feed gas mixture is fed and a l

A process of separating hydrogen from gas mixtures comprising: (A) contacting one side of a semi-permeable membrane with a feed gas mixture containing hydrogen under pressure, wherein the membrane divides a separation chamber into a higher pressure side into which the feed gas mixture is fed and a lower pressure side; (B) maintaining a pressure differential across the membrane under conditions such that hydrogen selectively permeates through the membrane from the high pressure side to the low pressure side of the membrane; (C) removing from the low pressure side of the membrane permeated gas which is enriched in hydrogen; and (D) removing from the high pressure side of the membrane non-permeated gas which is depleted in hydrogen wherein the membrane comprises a thin discriminating layer consisting predominantly of a polycarbonate polymer derived from a bisphenol corresponding to Formula I: [Figure] Formula I wherein R at each occurrence is independently hydrogen, chlorine, bromine, or C1-4 alkyl and R1 is －CO－, －S－, －SO2－, －O－, or a C1-6 divalent hydrocarbon radical,, with the proviso that at least about 25 weight percent of the moieties derived from the bisphenol of Formula I present in the discriminating layer bear R groups which are exclusively bromine or chlorine, wherein said membrane possesses a separation factor between hydrogen and light hydrocarbons of at least about 50 at a temperature of approximately 25°C., and wherein said membrane is characterized by a separation factor between hydrogen and methane of at least about 100 at a temperature of approximately 35°C.