Porous Carbon Captures Greenhouse Gas
Keith Gubbins of North Carolina State University, Raleigh, in collaboration with industrial partners, has discovered carbon materials that adsorb (hold on their surface) large amounts of the greenhouse gas carbon dioxide (CO2).Their experiments have shown how to select and create the materials that adsorb CO2 most effectively based on pore size and shape.
This finding has major implications for developing more sustainable processes to produce and burn fossil fuels and to significantly reduce greenhouse gas emissions. It also provides a framework for developing porous carbons for optimal removal of CO2 from industrially generated gas mixtures, and creates a knowledge base for developing these materials.
Porous carbons are inexpensive, adsorbent materials that are widely used for energy storage and environmental remediation. However, in the past there was no way to determine which materials were most effective. Now, by carefully choosing the proper materials, reaction conditions and finishing treatment, researchers can finely tune porous carbons. Because the structural characteristics of porous carbons are extremely diverse, the challenge in using these materials is learning how structural characteristics relate to performance.
Gubbins and his team used computer simulations to understand how porous carbons may be optimally tuned to remove CO2 from industrial point sources and natural gas. Their work has revealed that a significant trade-off exists between selectivity and capacity. Selectivity is the ability of a special porous solid carbon to preferentially adsorb CO2 gas over other industrially generated gases. Capacity is the ability to remove large amounts of CO2 gas.