A solid molecular basket sorbent for CO2capture from gas streams with low CO2concentration under ambient conditions

In this paper, a solid molecular basket sorbent, 50 wt% PEI/SBA-15, was studied for CO2 capture from gas streams with low CO2 concentration under ambient conditions. The sorbent was able to effectively and selectively capture CO2 from a gas stream containing 1% CO2 at 75 °C, with a breakthrough and saturation capacity of 63.1 and 66.7 mg g−1, respectively, and a selectivity of 14 for CO2/CO and 185 for CO2/Ar. The sorption performance of the sorbent was influenced greatly by the operating temperature. The CO2-TPD study showed that the sorbent could be regenerated under mild conditions (50–110 °C) and was stable in the cyclic operations for at least 20 cycles. Furthermore, the possibility for CO2 capture from air using the PEI/SBA-15 sorbent was studied by FTIR and proved by TPD. A capacity of 22.5 mg g−1 was attained at 75 °C via a TPD method using a simulated air with 400 ppmv CO2 in N2.