| 초록 |
Control of carbon dioxide emissions without significant penalties requires effective CO2 scrubbing from point sources, such as fossil fuel burning power plants, cement factories and steel making. Capturing process is the most costly; hence the research is directed to finding solutions to it. Solids with slight chemisorptive nature are identified as most likely candidates for a sustainable solution. Nanoporous (pore size ＜ 100 nm) materials show considerable CO2 uptakes and are likely to replace monoethanol amine (MEA) solutions for industrial CO2 capture. We have developed nanoporous covalent organic polymers (COPs), which show significant capacities and selectivities for CO2. To name a few, COP-1 shows 5.6 g/g CO2 uptake at 200 bar and 45 oC, COP-2 shows a CO2/H2 selectivity of over 10k:1, COP-79 has a CO2/N2 selectivity of 308 at 50 oC, COP-83 has CO2 uptake capacity of 5 mmol/g at 298 K and 1 bar and COP-97 showed an uptake of 8 % (w/w) CO2 in 2 minutes from a simulated flue gas mixture (CO2 15%, H2O 3.8%, He 81.2%, 40 C, flow rate : 80 mL/min). Chemical grafting of amines also show considerable enhancement, though a sweet spot exists. Our results point to an ideal nanoporous structure to be made from a highly porous, inexpensive, physisorptive solid, which is chemically modified with chemisorptive functionalities such as amines. |
