Enhanced CO<sub>2</sub> Capture Durability and Mechanical Properties Using Cellulose-Templated CaO-Based Pellets with Steam Injection during Calcination
Nai Rong, Jiuheng Wang, Kaiwei Liu, Long Han, Zhengyong Mu, Xvqing Liao, Wenjia Meng
Abstract
Cellulose-templated CaO-based pellets were prepared via an extrusion–spheronization method. However, the CO 2 capture capacity of the modified sorbents still deteriorated rapidly after multiple cycles, and the mechanical properties were also reduced. Steam injection during calcination was conducted to enhance the CO 2 capture performance of the sorbents. The modified pellets with 10 vol % steam injection present a faster carbonation rate compared to sorbents calcined under higher steam concentrations. A CO 2 uptake of 0.32 g/g was obtained after 20 cycles, 133 and 60% higher than the raw sorbent and modified sorbent without steam reactivation. Moreover, the simultaneous thermal and atmosphere-induced sintering resulted in a nearly 4 times enhancement of the mechanical strength of the sorbents from 3.9 to 14.7 N. Under the harsh environment (calcined at 950 °C), the presence of steam further aggravated the sintering of the sorbent, resulting in a dramatic decrease in CO 2 uptake.