Leo Ernest Krys

US Patent:

50964860, Mar 17, 1992

Filed:

Dec 13, 1990

Appl. No.:

7/627061

Inventors:

Corby G. Anderson - Silverton ID
Leo E. Krys - Kellogg ID
Kevin D. Harrison - Albuquerque NM

Assignee:

Sunshine Precious Metals Incorporated - Boise ID

International Classification:

C22B 308

US Classification:

75734

Abstract:

A process for extracting silver, copper, zinc, arsenic and iron from sulfide materials by leaching under relatively mild oxygen pressure and temperature conditions with sulfuric acid and sodium nitrite.

US Patent:

52903389, Mar 1, 1994

Filed:

Oct 16, 1992

Appl. No.:

7/962899

Inventors:

Corby G. Anderson - Silverton ID
Suzzann M. Nordwick - Wallace ID
Leo E. Krys - Kellogg ID

Assignee:

Sunshine Mining Company - Kellogg ID

International Classification:

C01B 2700

US Classification:

75703

Abstract:

An antimony recovery process is disclosed in which antimony-containing material is leached in a solvent including elemental sulfur and a caustic to preferentially leach antimony. The antimony-containing leach liquor from the leaching step is separated from the insoluble residue by filtration, and the antimony compounds in the separated leach liquor are crystallized to separate the antimony compounds from impurities which are left in solution in the leach liquor. The crystals are then redissolved and treated to create marketable antimony products of high purity, such as antimony metal, sodium hydroxy antimonate, sodium antimonate, antimony pentoxide, and antimony pentasulfide. Alternatively, the crystallized antimony compounds comprising primarily sodium thioantimonate crystals may be recovered and sold without further treatment. Waste products may be treated with soluble iron compounds and lime to render the waste products safe for disposal. Additionally, feed material having a high weight ratio of soluble arsenic to soluble antimony may be pretreated, if desired, to improve the purity of the recovered antimony products and to remove the arsenic for further treatment or disposal.