Process

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  Metal Oxide Powder

  Metalysis purchases metal oxide powder from ore refiners and other intermediaries. As the FFC process only removes the oxide ion, the purity of our product is dependent on the purity of the oxide feedstock.

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  Cathode Preforms (metal oxide)

  A considerable section of Metalysis’ IPR has been generated in the preparation of the oxide preform. The metal oxide needs to be exposed to the reduction vessel in a form that is sufficiently porous to permit CaCl2 ingress, whilst maintaining sufficient mechanical strength to avoid the preform disintegrating once the oxide ions have been removed.

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  Molten Salt Electrolysis

  A potential of approximately 3 volts is applied between anode and cathode. At the three-phase interface between the cathode preform, the calcium chloride and the current collector, the oxide ion is removed and conveyed via the electrolyte to the anode, where it reacts with the carbon and evolves as a gas.

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  FFC Product (Metal Sponge)

  At the conclusion of the reduction (between 4 and 12 hours) a metal sponge remains at the cathode. This sponge reflects the shape of the preform and potentially can utilise near-net shape technologies to form end-products with low yield losses. By comparison with the Kroll process, the FFC sponge is consistently purer with a uniform morphology throughout.

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  Light Crushing/Milling

  The mechanical strength of the FFC sponge produced is dependent on the melting point of the metal. It can hence be either very loosely or more strongly bonded (sintered). For instance tantalum sponge breaks into powder during washing, whereas the titanium product requires some light milling to convert the porous sponge into a jagged-edged powder that is similar to hydride-dehydride (HDH) product.

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  Washing in Water

  The sponge product has small levels of residual calcium and chloride (from the electrolyte) which are then dissolved out in deionised or distilled water. Depending on the purity requirements of the end product, some light leaching may be necessary to remove surface impurities.

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  Dried Metal Powder

  Once washed, the products is dried, bags and prepared for despatch.