Carbon Dioxide Absorption via Ultra-high Surface Area Carbon

The increase in CO2 in atmosphere can be attributed to vehicular emissions, coal/natural gas power plants, and industrial processes. CO2 removal from atmosphere is considered critical for reducing climate change effects; Current CO2 capture is performed using amine-based scrubbing systems via absorption–regeneration technology. However, amine based CO2 removal is energy intensive and not cost-effective. Another challenge with current scrubbers is amine-based corrosion of process equipment and pipes. Therefore, there is a need for alternative solutions for reducing CO2emissions on an industrial scale using cost effective techniques. Activated carbons have been investigated as suitable candidates for CO2 capture. They do not require any moisture removal prior to CO2 absorption, they can absorb CO2 at ambient pressures and are easy to regenerate. Compared to zeolites, which have also been proposed as CO2 absorbed, activated carbonshave advantages such as lower cost, higher hydrophobicity, and ~50% lower energy requirements for regeneration. However, compared to zeolites, activated carbon have lower CO2 absorption capacity, which in turn is dependent on the surface area, pore size distribution, and surface chemistry. The first two properties is inherent to the activated carbon material used. Recently, we have been working on ultra-high surface area carbon powder, where we significantly increase the surface area of powder activated carbon by controlled burning of a polymer substrate material over an elongated period of time. The resultant carbon material consists of stacked graphite sheets; we have demonstrated surface area of >3500 m2/g, compared to 1000 m2/g for commercially activated carbon powder, ~2000 m2/g for specialty activated carbon powder such as Kuraray 50 PF, and ~3000 m2/g for graphite/graphene based powders. Additionally, the pores of the activated carbon possess the right distribution in terms of meso and micropores, which is required for efficient carbon dioxide adsorption. The material is produced via a scalable process, and costs comparable to commercially available specialty activated carbon powder, but much less than graphene/graphite powders. In this Phase 1 proposal, we will evaluate extruded form of ultra high surface are carbon as CO2adsorbent under conditions similar to post-combustion CO2 capture in a fixed-bed adsorption unit. We will test the material for CO2/N2 selectivity, reversible adsorption, cyclability and durability. Finally, a cost benefit analysis will be performed to compare the carbon dioxide capture potential of the activated carbon presented here with current state-of-the-art technologies.