Following the element plutonium, americium and curium are the sixth and seventh elements in the actinide series. The primordial americium and curium isotopes that formed during the creation of the solar system billions of years ago have decayed away. Today, residual amounts of americium and curium isotopes present in nature are anthropogenic, originating from human activities such as nuclear weapons testing or nuclear energy generation. All americium and curium isotopes are highly radioactive and pose extreme health hazards to humans, especially when ingested or inhaled. Complexation reactions with environmentally relevant ligands, separation chemistry, the mechanistic studies of the processes that Am(III) and Cm(III) undergo at the solid–liquid interface in nature, and innovative process applications have been the focus of many studies during recent decades.

In general, the trivalent oxidation state of americium and curium is the most stable under environmental conditions. As hard cations, the Am³⁺ and Cm³⁺ ions form strong complexes with hard donor ligands and adsorb readily on surfaces. In the absence of carbonate, hydrolysis leads to sparingly soluble Am(III) and Cm(III) hydroxide complexes. Americium and curium are commonly used in home smoke detectors and for oil-well logging (²⁴¹Am), and as radioisotope thermoelectric generators (²⁴⁴Cm).