Methods, systems and media for separating polymer mixtures. A mixture including polymeric components is provided. A particulate media is added to the mixture, where the particulate media can selectively mediate a triboelectric charging of the polymer mixture. The media includes a polymeric material having a selected position within an electrostatic charging sequence and a functional additive. The mixture is triboelectrically charged with the media. Two or more components of the polymer mixture are separated according to the triboelectric charge. A portion of the particulate media can be recovered using a recovery process, where the functional additive is selected for compatibility with the recovery process.