Patent ID: 7011133

Claim:
A method of filtering molten aluminum containing suspended particles using a filter material dissolvable in molten aluminum to recover aluminum occluded in said filter material after filtering, the method comprising the steps of: (a) providing a source of molten aluminum to be filtered; (b) providing a filter material dissolvable in molten aluminum; (c) providing a casting mold having a sprue and gating system for casting aluminum products, said sprue and gating system containing said filter material; (d) introducing molten aluminum through said sprue, filter material and gating system to said mold; (e) solidifying said molten aluminum in said sprue, gating system and mold to provide a cast product having solidified metal in said sprue and gating system attached thereto; (f) separating said solid aluminum in said sprue and gating system from said cast product to provide solid aluminum containing said filter material embedded therein; and (g) dissolving said solid aluminum and filter material in molten aluminum, thereby recovering said aluminum occluded in said filter material.