1 research outputs found
Durability of CaO–CaZrO<sub>3</sub> Sorbents for High-Temperature CO<sub>2</sub> Capture Prepared by a Wet Chemical Method
Powders of CaO sorbent modified with
CaZrO<sub>3</sub> have been
synthesized by a wet chemical route. For carbonation and calcination
conditions relevant to sorbent-enhanced steam reforming applications,
a powder of composition 10 wt % CaZrO<sub>3</sub>/90 wt % CaO showed
an initial rise in CO<sub>2</sub> uptake capacity in the first 10
carbonation–decarbonation cycles, increasing from 0.31 g of
CO<sub>2</sub>/g of sorbent in cycle 1 to 0.37 g of CO<sub>2</sub>/g of sorbent in cycle 10 and stabilizing at this value for the remainder
of the 30 cycles tested, with carbonation at 650 °C in 15% CO<sub>2</sub> and calcination at 800 °C in air. Under more severe
conditions of calcination at 950 °C in 100% CO<sub>2</sub>, following
carbonation at 650 °C in 100% CO<sub>2</sub>, the best overall
performance was for a sorbent with 30 wt % CaZrO<sub>3</sub>/70 wt
% CaO (the highest Zr ratio studied), with an initial uptake of 0.36
g of CO<sub>2</sub>/g of sorbent, decreasing to 0.31 g of CO<sub>2</sub>/g of sorbent at the 30th cycle. Electron microscopy revealed that
CaZrO<sub>3</sub> was present in the form of ≤0.5 μm
cuboid and 20–80 nm particles dispersed within a porous matrix
of CaO/CaCO<sub>3</sub>; the nanoparticles are considered to be the
principal reason for promoting multicycle durability