Amine-containing gel CO2 solid absorbent for low-cost capture from humid gas streams

Problem solved

Conventional amine solution scrubbing requires high energy for regeneration, equipment corrosion management, and pre-drying of gas streams. This solid absorbent operates efficiently under high relative humidity without pre-drying, and its weaker CO2 bond enables desorption at lower temperature, reducing total capture energy and cost.

Application contexts

• Post-combustion CO2 capture from industrial exhaust
• Direct air capture (DAC) from ambient atmosphere
• CO2 enrichment for agricultural greenhouses
• CO2 capture from distributed emission sources (water heaters, boilers)

Technical principle

Amine-containing hydrogel particles (microgels/nanogels) are designed so that amine functional groups reversibly bind CO2. The gel structure maintains high amine accessibility even in humid conditions. The pKa of ammonium ions is tuned so that CO2 desorption occurs at lower temperature than conventional amine solutions. The absorbent can be deployed as packed bed particles or as a microgel nanomembrane coating on porous substrates for membrane separation.

Typical use cases

• Capturing CO2 from gas-boiler exhaust for local methanation
• Atmospheric CO2 capture for greenhouse CO2 fertilization
• Point-source CO2 capture from cement or steel plant flue gas