Abstract: A sorbent for capture of formaldehyde, including a hydrophilic amorphous precipitated silica material having a BET surface area of at least 200 m2/g, and an organic compound in the form of polyethylenimine (PE I) bound to a surface of the amorphous precipitated silica material.

Abstract: A sorbent for capture of ethylene gas includes an amorphous precipitated silica material having a BET surface area of at least 200 m2/g and an organic compound in the form of an amine, an imine or an amide bound to a surface of the amorphous precipitated silica material. The organic compound is configured for chemisorption of ethylene. An ethylene gas filtration system for a refrigerator includes an ethylene gas filter including the sorbent and a fan. The ethylene gas filter is mounted in conjunction with the fan such that gas is actively circulated through the ethylene gas filter by means of the fan. The organic compound may be triisopropanolamine, polyethylenimine or polyamide.