Activated carbon-based scavengers Ethylene can be removed by a system using various metal catalysts on activated carbon. This type of scavenger is more popular in Japan. Examples:-- SendoMate from Mitsubishi, which is based on a palladium catalyst -- Hatofresh System from Honshu Paper, which is based on activated carbon impregnated with bromine-type inorganic chemicals -- Neupalon from Sekisui Jushi (Japan)