Zeolites and composites incorporating zeolites
According to the invention there is provided a zeolite having a porous structure produced by forming the zeolite on a porous carbon substrate which has been substantially or completely removed, wherein (i) the zeolite was formed on the substrate at a loading of at least 8% by weight and/or (ii) the zeolite has a reinforcing layer.
1. A composite material comprising a porous carbon substrate and an ion exchanged zeolite formed on the substrate, or a porous exchanged zeolite produced from said composite material by substantially or completely removing said substrate, wherein the ion exchanged zeolite is one of zeolite LTA, zeolite X, zeolite Y, or zeolite H-Sodalite.
2. A composite material comprising a porous carbon substrate and an ion exchanged zeolite formed on the substrate, or a porous exchanged zeolite produced from said composite material by substantially or completely removing said substrate, wherein the ion-exchanged zeolite comprises Ag or Li cations.
3. A composite material comprising a porous carbon substrate and an ion exchanged zeolite formed on the substrate, or a porous exchanged zeolite produced from said composite material by substantially or completely removing said substrate, wherein the ion exchanged zeolite is Ag + LTA, Li + X or H + LTA/X.
4. A composite material comprising a porous carbon substrate and an ion exchanged zeolite formed on the substrate, or a porous exchanged zeolite produced from said composite material by substantially or completely removing said substrate, wherein the ion exchanged zeolite comprises a metal cation.
5. A method of adsorbing a gas comprising the steps of:
providing a composite material including a porous carbon substrate and a zeolite formed on the porous carbon substrate, or a zeolite produced from said composite material by substantially or completely removing said substrate; and
exposing the composite material or zeolite to the gas so that the gas is adsorbed by at least the zeolite;
wherein the gas is carbon monoxide, carbon dioxide, a hydrofluorocarbon, ammonia, water vapor or methane.
6. A method according to claim 5 , wherein the hydrofluorocarbon is 1,1,1,2 tetrafluoroethane.
7. A method according to claim 5 , wherein the composite material or zeolite is exposed to carbon dioxide and ammonia and/or water vapor so that carbon dioxide and ammonia and/or water vapor are adsorbed by at least the zeolite.
8. A method according to claim 5 , wherein the composite material or zeolite is exposed to carbon monoxide and ammonia and/or water vapor so that carbon monoxide and ammonia and/or water vapor are adsorbed by at least the zeolite.