Nano-engineered natural sponge as a recyclable and deformable reactor for ultrafast conversion of pollutants from water

Abstract An alkaline-modified natural sponge was applied as support of gold and silver nanocatalysts and a deformable reactor to hold the reaction solution, quickly adsorb several kinds of environmental pollutants (4-nitrophenol, hexavalent chromium, and methyl orange) and efficiently catalyse their conversion. As the reaction solution is sustained in the connecting micro-pores constructed by the stretched and knotted sponge fibers, the catalytic reaction is free from external mass transfer and suffers slight internal mass transfer limitation. This batch-wise reaction system employing an operation procedure of injection-extrusion achieved a nearly complete conversion of the reactants within 1 min or much less. This compressible support can also be packed in a continuous flow reaction system and can be repeated use for 37 times without any loss of catalytic activity. This study provides a generalizable and straightforward strategy for utilizing deformable soft supports that may inspire some unique industrial applications.