A methodology for efficient CO₂ capture using organic carbonates

Background

The field of carbon capture technology is crucial in addressing the growing concerns over climate change and the increasing concentration of carbon dioxide (CO₂) in the atmosphere. Traditional energy production methods, particularly those reliant on fossil fuels, release significant amounts of CO₂, contributing to global warming.

As industries and governments worldwide strive to reduce carbon emissions, the development of efficient and cost-effective CO₂ capture technologies has become a priority. These technologies aim to capture CO₂ from industrial emissions before they reach the atmosphere, thereby mitigating their environmental impact. The need for such technologies is underscored by international climate agreements and policies that set ambitious targets for reducing greenhouse gas emissions.

Current approaches to CO₂ capture, such as chemical absorption using amines, face several challenges that limit their widespread adoption. These methods often involve high energy consumption due to the need for solvent regeneration, which can be economically and environmentally costly. Additionally, the chemical solvents used can degrade over time, leading to reduced efficiency and the need for frequent replacement. This degradation can also result in the formation of harmful by-products, posing further environmental and health risks.

Furthermore, existing technologies may not be suitable for all industrial applications, particularly those requiring operation under varying conditions of pressure and temperature. These limitations highlight the need for innovative solutions that can offer improved efficiency, stability, and adaptability in CO₂ capture processes.

Technology overview

The technology involves the physical capture of CO₂ using dimethyl carbonate (DMC) as a solvent. The process is designed to efficiently capture CO₂ gas at a flow rate of 90 mL/min over a one-hour experiment. Key features include the use of a pH sensor and temperature monitoring to ensure optimal conditions for CO₂ capture. The capture capacity is determined through a double acid-base titration method, using 20 mL samples of DMC and titrants such as 1 M HCl and KOH.

The results showed that a 2 wt.% concentration of DMC demonstrated optimal performance, achieving a CO₂ loading close to 1 and a 6.8-fold increase in efficiency compared to deionized water. Notably, DMC undergoes no chemical modification after the CO₂ capture reaction, indicating a purely physical interaction.

This technology is differentiated by its use of DMC, which shows a high CO₂ capture capacity without chemical alteration, making it a sustainable option for long-term CO₂storage. The solvent’s ability to retain 80% efficiency after 45 days under ambient conditions highlights its stability and effectiveness. Additionally, the comparative analysis with other solvents like ethylene carbonate (EC) demonstrates DMC’s superior performance in capturing CO₂. The ongoing research into capture kinetics and the physical absorption mechanism further underscores the technology’s potential to enhance CO₂ capture processes, making it a promising solution for reducing atmospheric CO₂ levels.

Benefits

Optimal CO₂ capture performance with 2 wt.% DMC (9.02 g CO₂/L)
6.8X increase in CO₂ capture compared to DI water
No chemical modification of DMC after CO₂ capture, indicating a physical interaction
80% retention efficiency of DMC after 45 days of storage under ambient conditions
High CO₂ capture capacity of both linear (DMC) and cyclic (EC) alkyl carbonates under ambient conditions