Scientists from MIT and Harvard have pioneered a method for the efficient transformation of carbon dioxide into a stable and secure formate that may serve as an alternative to fossil fuels and be utilized for long-term energy storage and production.
This novel process directly changes carbon dioxide to formate, a robust fuel that has indefinite storage potential and could be applied for residential heating or industrial power.
Globally, there’s an active pursuit to devise methods to remove carbon dioxide from the atmosphere or industrial emissions and repurpose it beneficially. A leading concept is to convert it into a stable fuel as a substitute for fossil fuels. However, previous conversion methods have faced issues like low carbon efficiency or the production of difficult-to-manage, toxic, or combustible fuels.
CO2 to Fuel Conversion Advancement
A new method by researchers at MIT and Harvard enables the conversion of carbon dioxide to formate, which can be utilized in fuel cells like hydrogen or methanol to generate electricity. This formate, which exists as a liquid or solid, is non-toxic, non-flammable, and can be stored and transported easily. It can remain stable for extended periods in conventional steel tanks.
An illustration depicts three components on a grey surface: a model house, a fuel cell between two metal plates with molecules, and an electrolyzer with a similar appearance to the fuel cell. Credits to Shuhan Miao, Harvard Graduate School of Design.
The procedure, developed by MIT and Harvard doctoral students and professors, is detailed in a recent open-access article in Cell Reports Physical Science. It has been shown in a small, lab-scale setup, with expectations for scalability to personal home heating or large-scale industrial applications.
Efficiency and Practicality Enhancements
Li details that other carbon dioxide to fuel conversion methods are generally two-staged, first turning the gas to a solid form like calcium carbonate, then later converting it to a fuel feedstock through an inefficient heating step. The new process, in contrast, boasts over 90 percent conversion efficiency without needing the inefficient heating phase, initially turning carbon dioxide to liquid metal bicarbonate. This is then electrochemically transformed into formate, using renewable electricity sources, and can be dried into a stable solid powder.
An electrolyzer schematic includes a bicarbonate cathode and various other components, credited to Shuhan Miao, Harvard Graduate School of Design.
The team’s innovations have turned a once inefficient chemical-conversion process into a practical solution.
Conversion Process and Uses
The carbon capture and conversion process begins with an alkaline solution-based capture concentrating carbon dioxide into a liquid metal-bicarbonate solution. Then, through an electrolyzer, this is converted into solid formate crystals with impressive carbon efficiency, as proven by lab experiments.
These crystals are extremely stable, offering a storage advantage over hydrogen and avoiding the toxicity issues associated with methanol. Formate’s benign nature, confirmed by safety standards, positions it as an ideal alternative.
Technological Enhancements
The team’s process design ensures a balanced pH for continuous conversion efficiency, overcoming issues that
