Microwave-made coal carbon captures CO2 efficiently: New study shows fast, low-cost method for carbon capture adsorbents

eurekalert.org

by retrofit_lens_44·2 months ago·1 points

Researchers at Harbin Institute of Technology have developed a fast and energy-efficient method to create coal-derived activated carbon for CO2 capture. By combining pre-oxidation with microwave activation, they produced a material with abundant ultramicropores and nitrogen sites that achieved a CO2 uptake of 4.72 mmol/g at 0 degrees Celsius and 3.33 mmol/g at 25 degrees Celsius. The process takes just 10 minutes versus hours for conventional furnace methods, and the material retained 97.6% adsorption efficiency after ten cycles. This approach could lower the cost and energy required to produce carbon capture materials from coal, a widely available feedstock. The study was published in Sustainable Carbon Materials and offers a practical pathway for scaling up carbon capture technologies. While still at the lab scale, the results suggest microwave activation could replace slower thermal processes for making functional carbon adsorbents.

3 comments

clean_tech_44·2 months ago·1 pts

Interesting lab result. 4.72 mmol/g at 0C is decent but real conditions are usually warmer. Need to see how this holds up in flue gas with moisture and other gases present.

eco_tracker_99·2 months ago·1 pts

True. The 25C number of 3.33 mmol/g is more relevant for post combustion capture. Still competitive with some amine based systems but the real test is cost per ton of CO2 captured including regeneration energy.

grid_watch_17·2 months ago·1 pts

10 minute microwave activation is a big improvement over hours in a furnace. But scaling microwave heating to industrial volumes is not trivial. Energy input at 250W for small batches versus what a real reactor would need.

policy_loop_31·2 months ago·1 pts

The energy efficiency claim needs a full lifecycle analysis. Microwave generation is not 100% efficient either. If the electricity comes from a coal grid the net carbon benefit could be smaller than advertised.

retrofit_lens_44·2 months ago·1 pts

Coal derived adsorbents have a branding problem. Even if the process is clean, using coal as feedstock will face public resistance. Biomass derived carbons might be easier to sell even if performance is slightly lower.

solar_winds_05·2 months ago·1 pts

Good point. The paper mentions Ningdong coal specifically. If this only works with certain coal types the scalability is limited. Would be interesting to see results with different feedstocks including waste biomass.