David L Mclaughlin

US Patent:

49137786, Apr 3, 1990

Filed:

Jan 2, 1989

Appl. No.:

7/305125

Inventors:

Ernest D. Lee - Ogden UT
David F. McLaughlin - Oakmont PA

Assignee:

Westinghouse Electric Corp. - Pittsburgh PA

International Classification:

C01G 2504
C01G 2704

US Classification:

203 29

Abstract:

Removal of aluminum and iron impurities is accomplished using an absorbing column containing potassium or sodium chloride, producing an aluminum and iron chloride-rich bottoms product and purified Zr(Hf)Cl. sub. 4 vapor at the top of the column. This invention is a continuous process for removing impurities of iron or aluminum chloride or both from vaporous zirconium chloride (or hafnium chloride or a mixture thereof). When iron is being removed from zirconium tetrachloride using potassium chloride, the process comprises: introducing impure zirconium chloride vapor into a middle portion of an absorbing column containing a potassium chloride-containing molten salt phase, the molten salt phase absorbing the iron chloride impurity to produce a zirconium chloride vapor stripped of iron chloride in the top portion of the column; introducing potassium chloride into a top portion of the column; controlling the top portion of the column to between 300. degree. -375. degree. C. ; heating a bottom portion of the column to 450. degree. -550. degree. C. to vaporize zirconium chloride from the molten salt; withdrawing molten salt substantially free of zirconium and hafnium chloride from the bottom portion of the column; and withdrawing zirconium chloride vapor substantially free of iron chloride impurity from the top of the column.