Process for making microporous membranes having selected gas-selective sites and the membranes so made
AssigneePraxair Technology, Inc.
InventorsJoseph Timothy Mullhaupt, Neil Andrew Stephenson, Frank Notaro, Ravi Prasad
Life of this patent
Estimating the term…
Abstract
A process for making microporous membranes that incorporate selected gas selective species as surface sites in a controlled spacing and orientation manner and such membranes so formed being suitable for separating and purifying the selected gas from selected gas containing gas mixtures. An example is the use of oxygen selective transition element complexes (TECs) as surface sites for separating and purifying oxygen from oxygen-containing gas mixtures.
Claims35
A selected gas-selective microporous membrane having a surface diffusion of a selected gas using-selective sites which are selective at equilibrium employing reversible chemisorption and wherein said microporous membrane has a pore size of less than about 25 Å;
- and said selected gas selective sites have a footprint of less than about 200 (Å)2.
A process of making a selected gas-selective microporous membrane comprising the steps of
- (a) forming a microporous membrane having pore size of less than 25 Å and substantially removing any water and any other undesired adsorbed specie;
- (b) preparing a solution containing selected gas-selective sites;
- (c) contacting said microporous membrane with said solution of step (b) and controlling the selective sites in the solution so that said selective sites have a footprint of less than about 200 (Å)2 deposited on said microporous membrane;
- and removing solvent to produce a selective sites coated microporous membrane.
A process for making a selected gas-selective microporous membrane comprising the preparing of selected gas-selective sites in particle form and forming a sol-gel membrane with said selective sites particles in situ to produce a selected gas-selective microporous membrane wherein the membrane has a pore size of less than 25 Å, and the surface diffusion of the selected gas-selective sites have a footprint of less than about 200 (Å)2.
Dependencies are inferred from the claim text.