Development and evaluation of calcium oxide absorbent immobilized on fibrous ceramic fabrics for high temperature carbon dioxide capture

• An immobilization technique of the CaO on ceramic-based fibers was developed.
• The cyclic CO2 absorption of the samples is superior to pure CaO powder.
• The reactivity of the sample using yttria is maintained through the 12 cycles.
• The yttria is a superior substrate compared to the alumina for the CaO absorbent.

Calcium oxide is an effective carbon dioxide absorbent, but the cyclic lifetime and durability of the absorbent are key issues for its practicability. When used as pellets, pore plugging and sintering of particles have been found to be the major causes of the degradation of the absorption capacity in cyclic operation. In order to minimize these adverse effects, a simple and effective immobilization technique of the calcium oxide on fibrous ceramic-based fabrics (alumina and yttria) was developed. The prepared samples were characterized and evaluated by various analytical and experimental tools comprehensively. For a sample with 23 wt.% calcium oxide on the alumina fabric, continuous cyclic carbonation conversions of about 75% were achieved over 13 carbonation–calcination cycles under mild calcination condition at 750 °C and no CO2 in N2. Under more severe calcination condition at 850 °C and 20 wt.% CO2 in N2, the yttria fabric proved superior to alumina as a substrate of calcium oxide for carbon dioxide capture and the reactivity of the calcium oxide absorbent using the yttria fabric was maintained at the same level for 12 cycles.

Figure optionsDownload as PowerPoint slide