3D-printing of attapulgite monoliths with superior low-temperature selective catalytic reduction activity: the influence of thermal treatment

Attapulgite, as a versatile clay, can be constructed as an integral monolith through a 3D printing strategy to promote practical catalytic applications. Herein, we successfully realized 3D printing of attapulgite monoliths with the superior printing effect via a direct ink writing (DIW) technique. The influence of thermal treatment on DIW attapulgite monoliths was also systematically investigated at different calcination temperatures. Wherein, related characteristic changes of DIW attapulgite monoliths under thermal treatment were examined, including surface morphology, chemical properties, solidification shrinkage, rheological behaviors and compressive strength. Additionally, DIW attapulgite monoliths under thermal treatment were probed for the selective catalytic reduction of NOx with NH3 (NH3-SCR) performance, in which 3D-ATP-400 can exhibit superior low-temperature NH3-SCR activity with almost 100% NOx conversion and N2 selectivity in the range of 40–70 °C. This study can provide a facile strategy for the design and preparation of 3D-printed attapulgite monoliths with superior low-temperature NH3-SCR performance under thermal treatment.