Abstract: A process for recycling spent potlining material from aluminum reduction cells contaminated with fluoride and aluminum values. The process comprises first reducing the average particle size of the spent potlining material to smaller than 28 Tyler mesh to form a powder. The powder is then treated with an aqueous sodium hydroxide solution containing about 10 to 60 g/L of sodium hydroxide at a temperature in the range of between 60.degree. and 90.degree. C. to form a solution containing fluoride and sodium aluminate and a residual solid. The solution is removed from the residual solid and the content of NaOH is adjusted in the solution to the range of about 10 to 60 g/L of NaOH, if the content differs from this range, to produce a solution suitable for cyanide destruction. This solution is then heated to a temperature in the range of about 160.degree. to 220.degree. C. at a pressure in the range of about 150 to 350 p.s.i. for a time of between about 1/2 and 3 hours to destroy cyanide values in the solution.

Abstract: A method of recovering an aluminum-containing metal from a scrap material containing the metal and an organic contaminant, such as paper, plastics, lacquer, paint or oil. The method involves creating a fluidized bed of solid particles, maintaining a zone of the bed at a temperature in the range of the melting point of the metal to 1000.degree. C., introducing the scrap material into the fluidized zone to cause decoating of the metal within a time in the range of 1 to 40 seconds, at least partially melting the metal, and removing the metal material from the fluidized bed. In this way, decoating and at least partial melting is achieved essentially at the same time for improved efficiency. Metals of different melting point may also be separated from each other by providing a series of temperature zones in the fluidized bed (or in a series of fluidized beds) of progressively increasing temperature.

Abstract: A process is described for recovering metal values, e.g., gallium, contained in an aqueous solution by extraction comprising the steps of contacting the aqueous solution with a water immiscible organic phase comprising a water-insoluble substituted 8-hydroxyquinoline whereby the metal values are transferred into the organic phase; separating the organic phase from the aqueous solution and recovering the metal values from the organic phase. The novel feature comprises recovering the metal values by contacting the organic phase containing metal values with an aqueous solution of a strong base whereby metal values are removed from the organic phase to the aqueous solution with the aqueous solution containing the recovered metal values having a concentration of at least 4.6 moles per liter total hydroxide, and then separating the metal values from the aqueous phase.