Method for Removing Non-Proton Cationic Impurities from an Electrochemical Cell and an Electrochemical Cell

Simple SummaryContent extracted from patent full text and abstract with AI.

This invention provides a method and apparatus for removing non-proton cationic impurities (such as metal ions) from the ionomer components of proton exchange membrane (PEM) electrochemical cells, especially PEM water electrolyzers. The process involves introducing an acidic regenerating fluid, such as carbonic acid formed by dissolving CO2 in water, into the cathode-side of the electrochemical cell during operation. This solution enables exchange of the contaminant cations with protons, purifying the membrane without causing corrosion or requiring process interruptions.

Use CasesContent extracted from patent full text and abstract with AI.

• Regenerative maintenance of PEM water electrolyzers used for hydrogen production.
• Improving the operational life and efficiency of fuel cells by routinely purging cation contaminants.
• On-line cleaning (without system shutdown) of industrial electrochemical devices with proton exchange membranes.
• Water treatment systems using PEM electrolyzers, ensuring membrane longevity and stable performance.

BenefitsContent extracted from patent full text and abstract with AI.

• Removes efficiency-reducing metal cation contaminants from PEM membranes without halting device operation.
• Reduces risk of corrosion and recontamination, since acid is only introduced on the cathode side and not into metal piping loops.
• Prolongs operational lifetime of expensive electrochemical stacks, reducing maintenance costs and downtime.
• Improves and restores voltage efficiency, lowering the energy cost of hydrogen or other electrolysis-based products.
• Applicable in situ, enabling real-time membrane regeneration in operating devices.

Technical Classifications (CPCs)

Inventors & Applicants

Patent Abstract

It is the objective of the present invention to provide a method and an electrochemical cell which allow to achieve a purification of the ionomer load of the proton exchange membrane causing less corrosion and other collateral effects to the electrochemical cell.With respect to the method, this objective is achieved according to the present invention by a method to remove non-proton cationic impurities from the ionomer comprised in a proton exchange membrane and the respective anode side and cathode side catalyst layer of an electrochemical cell, comprising the steps of:a) providing a supply path for an anode feed to the ionomer on the anode side of the proton exchange membrane;b) providing a supply path for a cathode feed to the ionomer on the cathode side of the proton exchange membrane; andc) bringing a regenerating fluid with acidic pH in contact to the ionomer on the cathode side of the proton exchange membrane to accomplish an ion exchange of the non-proton cationic impurities with protons and thus remove the non-proton cationic impurities from the ionomer into the regenerating fluid.These measures allow to remove the non-proton cationic impurities from the ionomer of the electrochemical cell without increasing the risk of corrosion and without an interruption of the process of the electrochemical cell.