Membraneless Electrochemical Device for pH Gradient Generation

Solution Overview

Problem

Current methods for carbon dioxide capture from seawater, such as bipolar membrane electrodialysis, are inefficient due to high energy consumption and require membranes that are costly and prone to fouling, limiting their effectiveness and durability.

Innovation Solution

A membraneless electrochemical device with two electrodes, each comprising a redox-active material, generates a pH gradient within a fluid stream by applying an electrical potential, allowing for efficient separation and capture of carbon dioxide without the need for a physical barrier, reducing energy consumption and manufacturing costs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If bipolar membrane electrodialysis is used to produce acidified and alkaline streams, then carbon dioxide capture from seawater is achieved, but energy consumption is high and manufacturing costs are increased due to membrane requirements

Engineering Contradiction:

Improvecarbon dioxide capture efficiencyVSAvoidenergy consumption

Core Design Contradiction:

ProductivityVSUse of energy by moving object

Solution Approach 1:

The patent removes the bipolar membrane component from the electrodialysis system, extracting only the essential function of generating pH gradients through redox reactions at electrode surfaces. This eliminates the need for expensive, fouling-prone bipolar membranes while maintaining the ability to produce acidified and alkaline streams for CO2 capture.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The invention replaces expensive, durable bipolar membranes with inexpensive, easily replaceable electrode materials coated with redox-active substances. The electrodes can be regenerated or replaced without requiring specialized membrane materials, significantly reducing manufacturing costs and material expenses.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

2Productivity

If bipolar membrane electrodialysis is used to produce acidified and alkaline streams, then carbon dioxide capture from seawater is achieved, but manufacturing costs are increased due to membrane requirements

Engineering Contradiction:

Improvecarbon dioxide capture efficiencyVSAvoidmanufacturing cost

Core Design Contradiction:

ProductivityVSEase of manufacture

Solution Approach 1:

The patent removes the bipolar membrane component from the electrodialysis system, extracting only the essential function of generating pH gradients through redox reactions at electrode surfaces. This eliminates the need for expensive, fouling-prone bipolar membranes while maintaining the ability to produce acidified and alkaline streams for CO2 capture.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The invention replaces expensive, durable bipolar membranes with inexpensive, easily replaceable electrode materials coated with redox-active substances. The electrodes can be regenerated or replaced without requiring specialized membrane materials, significantly reducing manufacturing costs and material expenses.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

3Productivity

If high concentrations of hydronium ions and hydroxide ions are produced in close proximity within the bipolar membrane, then pH gradient formation is achieved, but a minimum energy threshold is exceeded making the process inefficient

Engineering Contradiction:

ImprovepH gradient formationVSAvoidenergy consumption

Core Design Contradiction:

ProductivityVSUse of energy by moving object

Solution Approach 1:

The patent segments the single bipolar membrane system into separate acidification and alkalization chambers with independent electrode surfaces. This allows pH gradients to form in spatially separated regions, preventing the energy-intensive concentration of both hydronium and hydroxide ions in the same location and enabling more efficient operation at lower energy thresholds.

Inventive Principle:

Principle #1Segmentation

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The membraneless electrochemical device effectively creates a pH gradient, enabling efficient carbon dioxide extraction from seawater with lower energy consumption and reduced costs, while also allowing for the use of a wider range of fluid pH values and more durable, inexpensive materials.

Implementation Method 1

The first electrode comprises a first redox-active material configured to have a proton-coupled oxidation reaction with a first portion of the fluid feed stream

Methodology Applied

Scientific EffectProton-coupled oxidation reaction: Redox Reactions

Implementation Method 2

the second electrode comprises a second redox-active material configured to have a proton-coupled reduction reaction with a second portion of the fluid feed stream

Methodology Applied

Scientific EffectProton-coupled reduction reaction: Redox Reactions

Implementation Method 3

The energy source is configured to apply a first electrical potential and a second, reverse electrical potential across the first and second electrodes

Methodology Applied

Scientific EffectElectrochemical reaction: Electrolysis

Data Source

PatentUS11932560B2Electrochemical device for creation of pH gradients

Publication Date: 2024.03.19 XEROX CORP

AI summary

A membraneless electrochemical device comprises a fluid feed stream input to the membraneless electrochemical cell, a first electrode, and a second electrode. The first electrode comprises a first redox-active material configured to have a proton-coupled oxidation reaction with a first portion of the fluid feed stream, and the second electrode comprises a second redox-active material configured to have a proton-coupled reduction reaction with a second portion of the fluid feed stream. The first portion and the second portion of the fluid feed stream are separated. A first effluent stream comprises the first portion and has a first pH, and a second effluent stream comprises the second portion and has a second pH, different from the first pH.