Dry hydrated potassium carbonate for effective CO capture.

Dry hydrated potassium carbonate (DHPC) is a free-flowing powder prepared by uniformly mixing hydrated KCO and hydrophobic nanosilica. We demonstrated that DHPCs can absorb CO rapidly because of their high surface-to-volume ratio. Their CO capture performance is superior to that of 30 wt% monoethanolamine (MEA), an industry standard. DHPC-75 (containing 75 wt% KCO) has a CO uptake capacity of 233 mg g (90% saturation uptake within 13 min), higher than the widely used 30 wt% MEA aqueous solution (111 mg g, 90% saturation uptake within 25 min). DHPC-75 also exhibits an excellent cycling performance, thus becoming a promising candidate for practical application.