Journal
INTERNATIONAL JOURNAL OF GREENHOUSE GAS CONTROL
Volume 6, Issue -, Pages 164-170Publisher
ELSEVIER SCI LTD
DOI: 10.1016/j.ijggc.2011.11.006
Keywords
CO2 capture; CaO-based pellets; Ca-looping; Limestone; Acetification
Ask authors/readers for more resources
Pellets from natural and acetified Havelock limestone were synthesized and tested for in situ post-combustion CO2 capture in Ca-looping cycles. Natural kaolin and Al(OH)(3) obtained from acid leaching of kaolin were used as binders. The results showed that after 30 cycles, pellets prepared from acetified limestone with 10 vol.% acetic acid and CaO/Al(OH)(3) mass ratio of 5.5 had a somewhat higher CO2 uptake of 0.13 g/g (g CO2/g sorbent), compared to 0.12 g/g for pellets prepared from natural limestone and Al(OH)(3). These uptakes corresponded to 56% and 36.7% of their initial capture capacities, respectively. By contrast, natural sorbent and pellets prepared with kaolin demonstrated a significant decay in their CO2 uptake down to 21% and 21.7% of their initial capacities, respectively. The superiority of acetified sorbents with Al(OH)(3) binders appears to be due to the creation of a highly developed porous structure. In particular, alpha-Al2O3 generated from Al(OH)(3) appears to create a stable framework dominated by mesopores, which also inhibits sintering over multiple cycles. However, acetification itself widens pores and alters pore surface area and volume, providing more space for CaCO3 growth. Unfortunately, water addition during pellet synthesis appears to compromise this porous structure, thus reducing the original benefits of acetification. (C) 2011 Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available