Systems and methods for recovery of molten metal are generally described. Certain systems comprise a reactor (e.g., a reduction cell such as an electrolytic cell comprising an anode, a cathode, and an electrolyte) comprising molten metal within a container; and a collection vessel at least partially contained within the container of the reactor, the collection vessel comprising an opening fluidically connected to the container of the reactor. Some systems comprise a reactor; and a collection vessel comprising a first opening fluidically connected to the reactor and a second opening fluidically connected to a source of gas (e.g., inert gas) and to a source of negative pressure.

An improved method for recovering metals from spent supported catalysts, including spent supported hydroprocessing catalysts. The method and associated processes comprising the method are useful to recover spent supported catalyst metals used in the petroleum and chemical processing industries. The method generally involves a combination of a pyrometallurgical and a hydrometallurgical method and includes forming a potassium carbonate calcine from the spent supported catalyst containing Group VIIIB/Group VIB/Group VB metal compound(s) combined with potassium carbonate, and extracting and recovering soluble Group VIB metal and soluble Group VB metal compounds from the potassium carbonate calcine.