CO_2 Capture Performance and Attrition Property of CaO-Based Pellets Manufactured from Organometallic Calcium Precursors by Extrusion

摘要

Calcium looping has been identified to be one potential candidate for CO_2 capture; however, the sorbent used in this process still needs to be improved on both the physical and chemical performance. In this work, we report the manufacture of CaO-based pellets from organometallic calcium precursors and cement by an extrusion method. The reactivity and recyclability of the pellets were tested in a thermogravimetric analyzer and a lab-scale fixed-bed reactor for high-temperature CO_2 capture. After 20 cycles of typical carbonation and calcination, all synthetic pellets demonstrated good CO_2 uptakes, and the best value was 0.38 g of CO_2/g of sorbent, around 90% higher than that of powdered limestone, which was further confirmed by isothermal tests of 200 cycles. Also, attrition property of these pellets was evaluated with different techniques. It was found that the synthetic pellets using organometallic materials as calcium precursors have the same attrition behavior to the pellets derived from inorganic calcium hydroxide.