Process for producing high purity aluminum materials

Abstract

A process for producing high purity alumina (HPA) or high purity aluminium salts from an aluminium-bearing material, such as is disclosed. An aluminium-bearing solution is first obtained by either dissolving or leaching the aluminium-bearing material. Aluminium is then selectively extracted by liquid-liquid or liquid-solid extraction to obtain an aluminium-enriched liquid or aluminium-enriched solid phase. Minor metal impurities still remaining in the aluminium-enriched liquid or solid phase are removed by scrubbing the aluminium-enriched liquid or aluminium-loaded ion exchange resin with an aqueous solution thereby producing a metal impurity-depleted aluminium-enriched liquid or metal impurity-depleted aluminium enriched solid phase. Aluminium is then stripped from the scrubbed liquid or solid phases with an acidic aqueous solution to produce an aluminium-enriched aqueous solution. High purity aluminium salts may be crystallised from said solution. Alternatively, the pH of said solution may be raised to precipitate an aluminium precipitate, such as Al(OH)3, which is then calcined to produce HPA.

Dependencies are inferred from the claim text.