A novel method to make regenerable core-shell calcium-based sorbents

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Developing efficient and reusable sorbents is crucial for effective carbon dioxide capture.
• Existing sorbent materials often face challenges with stability, cost, or regeneration.

Purpose of the Study:

• To prepare and characterize a novel core-shell sorbent for carbon dioxide (CO2) absorption and desorption.
• To evaluate the reusability and mechanical properties of the developed sorbent.

Main Methods:

• A two-step granulation process was employed to create calcium oxide core and clay shell pellets using calcium carbonate, clay, and water.
• Pellets underwent calcination at 1200°C, followed by mechanical property testing (crush load, attrition index).
• CO2 absorption and desorption cycles were performed at specified temperatures to assess performance and reusability.

Main Results:

• The core-shell sorbent exhibited a maximum CO2 weight gain of 38% at or below 300°C.
• Pellets demonstrated good mechanical integrity with a crush load of 35 N and an attrition index of 0.035 wt%/h.
• Efficient regeneration was achieved via desorption in nitrogen at 800°C, restoring the sorbent for reuse.

Conclusions:

• The prepared calcium oxide-clay core-shell sorbent is a promising material for reusable carbon dioxide capture.
• Its robust structure and high absorption capacity, coupled with effective regeneration, indicate suitability for industrial applications.
• The use of readily available materials like calcium carbonate and clay contributes to the cost-effectiveness of this sorbent technology.