The phrase "separated plutonium" refers to a process in which the element plutonium is taken out or extracted from other substances it may be mixed with. Full definition
The controversy began to make clear the impossibility of separating the plutonium issue from the broader energy picture. (religion-online.org)
The irradiated pellets are then dissolved and ORNL staff use a chemical process to separate the plutonium from remaining neptunium. (ornl.gov)
Japanese nuclear operators and governments also must find safe and secure ways to manage growing stockpiles of irradiated nuclear fuel and weapon - usable separated plutonium. (scientificamerican.com)