Electrochemical device and method for adjusting carbon dioxide concentration in indoor atmospheres
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for reducing carbon dioxide concentrations in indoor air are energy-intensive and inefficient, with high energy costs associated with frequent ventilation and existing regenerative CO2 removal systems, which also generate heat and have limitations in continuous processing.
Innovation Solution
An electrochemical device with a cathode and anode chamber separated by a solid electrolyte membrane, using a polymerized ionic liquid membrane to transport ionic carrier species, allowing for continuous and efficient CO2 removal or addition to indoor air at low temperatures and power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If regenerative CO2 removal systems using absorbents are used, then CO2 can be removed from indoor air, but the system becomes heavy and requires high temperature heating for regeneration
Solution Approach 1:
The patent replaces the thermal regeneration mechanism with an electrochemical mechanism. Instead of heating absorbents to high temperatures to release CO2, the invention uses electrochemical reactions at electrodes to continuously remove CO2 through a membrane, substituting mechanical/thermal processes with electrochemical ones.
Solution Approach 2:
The invention changes the operating parameters from high temperature (above 150°C) to ambient or low temperatures by using electrochemical potentials. The electrochemical cell operates at much lower temperatures than thermal regeneration systems, fundamentally changing the temperature parameter of the CO2 removal process.
2Quantity of substance
If regenerative absorbent systems are used, then CO2 can be removed, but continuous processing is limited and large heat is generated
Solution Approach 1:
The patent replaces the thermal cycle of absorbent regeneration with a continuous electrochemical process. The electrochemical cell continuously converts CO2 to carbonate ions at the cathode and regenerates the carrier at the anode without requiring thermal input, eliminating the heat generation problem of regenerative systems.
Solution Approach 2:
The electrochemical system enables continuous CO2 removal through uninterrupted electrochemical reactions. Unlike batch regenerative systems that require periodic heating cycles, the electrochemical cell operates continuously with constant ion transport through the membrane, maintaining steady-state CO2 removal without interruption.
3Reliability
If frequent ventilation is used to maintain CO2 levels, then indoor air quality can be maintained, but energy cost becomes quite high
Solution Approach 1:
The patent extracts and removes only the CO2 component from indoor air using the electrochemical cell, rather than replacing all indoor air through ventilation. The system selectively removes CO2 through electrochemical reactions while recirculating the bulk air, extracting the harmful component without the energy cost of full air replacement.
Solution Approach 2:
The invention changes the approach from bulk air exchange to selective component removal. Instead of changing the entire air composition through ventilation, the electrochemical system specifically targets and removes CO2 molecules through electrochemical conversion to carbonate ions, fundamentally changing the parameter of what is being treated.
4Quantity of substance
If electrochemical methods with quinone carriers are used, then CO2 removal can be achieved, but oxygen stability is poor and CO2 removal flux is low
Solution Approach 1:
The patent uses a composite membrane system combining a polymer matrix with ionic liquid or ion-exchange functional groups. This composite structure provides both the mechanical integrity needed for stability and the ionic conductivity required for high CO2 flux, while the polymer backbone offers oxygen stability that simple quinone carriers lack.
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 electrochemical device enables continuous, energy-efficient CO2 removal or addition, reducing energy consumption and thermal load, while maintaining indoor air quality, and can be integrated into HVAC systems for widespread application.
Implementation Method 1
A reduction catalyst layer in the cathode chamber reduces carbon dioxide in the gas to form an ionic carrier species
Implementation Method 2
The membrane includes a polymerized ionic liquid. The membrane transports the ionic carrier species between the cathode chamber and the anode chamber when a voltage difference is applied across the membrane
Implementation Method 3
An oxidation catalyst layer in the anode chamber oxidizes the ionic carrier species to form carbon dioxide
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An electrochemical device suited to modifying a carbon dioxide concentration in an interior space includes a cathode chamber with an inlet which receives a feed gas containing carbon dioxide. A reduction catalyst layer in the cathode chamber reduces carbon dioxide in the gas to form an ionic carrier species. An anode chamber with an outlet outputs a gas comprising carbon dioxide. A solid electrolyte membrane spaces the anode chamber from the cathode chamber and transports the ionic carrier species between the cathode chamber and the anode chamber. The membrane includes an ionic liquid. An oxidation catalyst layer in the anode chamber oxidizes the ionic carrier species to form carbon dioxide. A voltage source provides a voltage difference across the membrane.