Ceramic foams with micron/sub-micron sized porous structure for efficient high-temperature particulate matter capture

Constructing high-performance air filters for high-temperature particulate matter (PM) removal is of great importance but remains challenging. Here we demonstrate the ceramic foam-based filters via polyurethane (PU) foaming using diatomite and kaolin powder as the starting materials. Diatomite was grafted by dodecanedioic acid (DA) to improve the dispersity in the PU slurry. The calcined products demonstrated a hierarchical pore structure with multiple well-controlled micron-sized window pores on the cell wall of the sub-micron bubble. The resulting products exhibited a high removal efficiency (96.3%) at a pressure drop of 33 Pa. This research showed that as-prepared ceramic foams can be potentially used as new high-temperature filters for high-temperature PM removal.