Enhanced metal recovery through oxidation in liquid and/or supercritical carbon dioxide

Patent metadata

Field	Value
Publication number	US-2017240434-A1
Application number	US-201715419184-A
Country	US
Kind code	A1
Filing date	Jan 30, 2017
Priority date	Feb 23, 2016
Publication date	Aug 24, 2017
Grant date	—

Abstract

Process for enhanced metal recovery from, for example, metal-containing feedstock using liquid and/or supercritical fluid carbon dioxide and a source of oxidation. The oxidation agent can be free of complexing agent. The metal-containing feedstock can be a mineral such as a refractory mineral. The mineral can be an ore with high sulfide content or an ore rich in carbonaceous material. Waste can also be used as the metal-containing feedstock. The metal-containing feedstock can be used which is not subjected to ultrafine grinding. Relatively low temperatures and pressures can be used. The metal-containing feedstock can be fed into the reactor at a temperature below the critical temperature of the carbon dioxide, and an exotherm from the oxidation reaction can provide the supercritical temperature. The oxidant can be added to the reactor at a rate to maintain isothermal conditions in the reactor. Minimal amounts of water can be used as an extractive medium.

First claim

What is claimed is:

1 . A method comprising: oxidizing a metal-containing feedstock in a reactor with liquid and/or supercritical fluid carbon dioxide and at least one oxidant, wherein optionally the oxidant is free of complexing agent and optionally the metal-containing feedstock is not subjected to ultrafine grinding.

2 . The method of claim 1 , wherein the oxidant is free of complexing agent and the metal-containing feedstock is not subjected to ultrafine grinding.

3 . The method of claim 1 , wherein the metal-containing feedstock is a mineral metal composition.

4 . The method of claim 1 , wherein the metal-containing feedstock is a refractory mineral composition.

5 . The method of claim 1 , wherein the metal-containing feedstock is a mineral metal composition comprising a high sulfide content or a high carbonaceous material content.

6 . The method of claim 1 , wherein metal-containing feedstock is a waste composition.

7 . The method of claim 1 , wherein aqueous alkali solution is also added to the reactor.

8 . The method of claim 1 , wherein oxidizing the feedstock is carried out with supercritical fluid carbon dioxide.

9 . The method of claim 1 , wherein the metal-containing feedstock is fed into the reactor at a temperature below the critical temperature of the carbon dioxide, and an exotherm from the oxidation reaction provides the supercritical temperature.

10 . The method of claim 1 , wherein the oxidant is added to the reactor at a rate to maintain isothermal conditions in the reactor.

Assignees

• Univ King Abdullah Sci & Tech

Inventors

• Blanco Mario
• Buttner Ulrich

Classifications

• C22B1/11

  Removing sulfur, phosphorus or arsenic other than by roasting · CPC title

• C01G49/14 Primary

  Sulfates {(C01G49/0018 takes precedence)} · CPC title

• C22B3/12

  in inorganic alkaline solutions · CPC title

• Y02P10/20

  Recycling · CPC title

• Y02P20/54

  using solvents, e.g. supercritical solvents or ionic liquids · CPC title