Fly Ash-derived Solid Amine Sorbents for CO2 Capture from Flue Gas

摘要

CO2 capture and storage from flue gas has been considered as a key option for greenhouse gas control. The challenge of CO2 capture is the high energy penalty resulting into the high capture cost. In this paper, it is reported that solid amine sorbents can be synthesized from fly ash successfully and they can be applied for CO2 capture from flue gas. The sorbent, PEI/FA, has improved sorption performance and allowed a low production cost. The effects of sorption temperature and PEI loading amount on CO2 sorption capacity were investigated. The CO2 sorption capacity, CO2 sorption rate and the regenerability of PEI/FA were evaluated by using thermogravimetric analyser (TGA). The highest CO2 sorption capacity of PEI/FA sorbents is 145.0 mg-CO2/g-sorbent at 90 °C under 10 % CO2 in N2. Comparing with the sorbents, which have the similar sorption capacity, the preparation cost of PEI/FA is significantly reduced. The multi-cycles of PEI/FA were conducted and the sorption capacity of the regenerated sorbent after 100 cycles was still maintain 90% of the initial sorption capacity. The sorbent also shows a fast CO2 sorption rate and the CO2 sorption capacity can reach about 75 % of saturation capacity at first 2 min. The results indicate that the PEI/FA synthesized by this environmental friendly and low cost method has potential application for low temperature CO2 capture in terms of its outstanding features such as high capture capacity, fast sorption/desorption rate, good regenerability, no corrosion and cost-effective.