Energy & Fuels, Vol.26, No.1, 154-161, 2012
Performance of Extruded Particles from Calcium Hydroxide and Cement for CO2 Capture
The reversible reaction of CaO with CO2 can be used for CO2 capture. However, two challenging problems, i.e., loss-in-capacity and high attrition rate for CaO-based sorbents, must be solved before it can be practically applied. In this paper, sorbents with various CaO contents were prepared from calcium hydroxide and cement using a screw extruder and the physical and chemical properties of the sorbents were obtained. The mechanical properties of sorbent particles were tested by friability and compression testers, and the sorption capacity and regenerability were measured in a thermogravimetric analyzer. It appears that the sorbents occupied acceptable attrition resistance and good mechanical strength. In the meantime, the sorbent particles showed higher CO2-capture capacities compared to pure CaO after 18 cycles, which was attributed to the stable phase of Ca12Al14O33 in the sorbents. The sorbent particles would be suitable for the calcium looping processes.