Recycling of used perfluorosulfonic acid membranes
AssigneeIon Power, Inc.
InventorsStephen Grot, Walther Grot
Life of this patent
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Abstract
A method for recovering and recycling catalyst coated fuel cell membranes includes dissolving the used membranes in water and solvent, heating the dissolved membranes under pressure and separating the components. Active membranes are produced from the recycled materials.
Claims23
A process for separation of components of catalyst coated membranes comprising:
- dissolving the catalyst coated membranes into a slurry of water and solvent;
- subjecting the slurry to a temperature of from 190° C. to 290° C. at a pressure of from 500 to 2000 psi for an effective period of time to obtain a pulp material;
- filtering the pulp material;
- and
- separating the components from the filtrate to obtain a first portion containing at least a majority of the catalyst and a second portion containing the membrane material.
A method for recovering used perfluorosulfonic acid membranes comprising:
- obtaining a slurry of water and solvent containing the catalyst coated membranes;
- subjecting the slurry to a pressure of from 500 to 2000 psi at a temperature of from 190° C. to 290° C. in an autoclave for an effective period of time to obtain a pulp material;
- filtering the pulp material to obtain a filtrate;
- and
- centrifuging the filtrate to separate the majority of the perfluorosulfonic acid membrane from the remainder of the filtrate;
- and
- recovering the perfluorosulfonic acid membrane material.
A method of recycling a used catalyst coated membrane material comprising fluorine containing polymer membrane and metal catalyst, comprising:
- decontaminating the used catalyst coated membrane to remove impurities;
- dissolving the used catalyst coated membrane in water and a solvent to form a slurry of dissolved fluorine containing polymer membrane together with the metal catalyst particles;
- subjecting the slurry to a temperature of at least 190° C. and pressure of at least 500 psi;
- separating the fluorine containing polymer membrane material from the metal catalyst;
- recovering the fluorine containing polymer membrane material and the metal catalyst and casting the recovered fluorine containing polymer membrane material into a recycled membrane.
A process for separating components of a composite material containing perfluorosulfonic acid polymer material and non-perfluorosulfonic acid polymer material, said process comprising:
- subjecting the composite material to a temperature of at least 200° C. in water and solvent for a time effective to form a suspension of the perfluorosulfonic acid polymer material and non-perfluorosulfonic acid polymer material in a liquid composition, wherein the suspension is formed under a pressure of from 500 to 2000 psi;
- and
- separating the non-periluorosulfonic acid polymer material from the liquid composition.
Dependencies are inferred from the claim text.