Improving the direct air capture capacity of grafted amines thermal treatment

This study investigates the effects of elevated temperature thermal treatments on the direct air capture of CO 2 by aminosilane-grafted SBA-15 silica sorbents. Exposing samples to high temperatures (200-250 °C compared to 80-120 °C) in an inert environment resulted in improved CO 2 capacity (5-21%) that was sustained over multiple adsorption/desorption cycles. Elevated thermal treatments increase the CO 2 capacity of aminosilane-grafted SBA-15 sorbents through freeing up additional surface hydroxyls and favoring CO 2 binding as carbamic acid.