David J Chaiko, 68Quakake, PA

2021024, Aug 12, 2021

Aug 27, 2019

17/272437

- Valby, DK
David J. Chaiko - Quakake PA, US

C22B 11/00
C22B 3/44
C22B 3/06

A method for removing sulfate iron-containing compounds from a low- to moderate-temperature metal sulfide leach circuit () is disclosed. A reactor () within a chloride leach circuit () and which is preferably maintained at a temperature between 20 and 150 degrees Celsius may be provided with a catalyst () comprising a material selected from the group consisting of: colloidal hematite, colloidal goethite, particulate containing FeOOH, particulate containing α-FeOOH, particulate containing γ-FeOOH, particulate containing FeO, particulate containing α-FeO, particulate containing γ-FeO, particulate containing FeO, particulate containing Fe(OH)SO, and a combination thereof. The catalyst () may also be used with heap leach and/or dump leach circuits (), without limitation. Methods for using and generating the catalyst () are also disclosed. In some embodiments, the catalyst () may be used as an anti-frothing agent (e.g., for zinc leaching, without limitation).

2017028, Oct 5, 2017

Sep 14, 2015

15/509147

David J. CHAIKO - South Jordan UT, US
- Valby, DK
Tom Walters - Medford OR, US
Sarah (Sally) Rocks - Sandy UT, US
Carlos Eyzaguirre - Draper UT, US

C22B 15/00
C22B 3/02

A method of improving metal leach kinetics and recovery during atmospheric or substantially atmospheric leaching of a metal sulfide is disclosed. In some embodiments, the method may comprise the steps of: (a) producing a metal sulfide flotation concentrate; (b) processing the metal sulfide concentrate in a reductive activation circuit that operates at a first redox potential, to produce a reductively-activated metal sulfide concentrate; and, (c) subsequently processing the activated metal sulfide concentrate in an oxidative leach circuit to extract metal values. In some disclosed embodiments, reductive activation steps may be employed prior to oxidative leaching steps (including heap leap leaching or bio-leaching steps). In some embodiments, physico-chemical processing steps may be employed during reductive activation and/or oxidative leaching. Systems for practicing the aforementioned methods are also disclosed.

2015021, Jul 30, 2015

Nov 11, 2013

14/417850

- Valby, DK
David J. Chaiko - South Jordan UT, US

C22B 15/00
C25C 1/12
C22B 4/08
C22B 4/04
C22B 3/08
C22B 3/20

A method of leaching a copper bearing sulfide mineral slurry containing chalcopyrite is described. The method comprises the steps of providing a slurry having chalcopyrite particles therein, exposing the slurry to an acidic leach solution, and chemically leaching copper from the slurry into the acidic leach solution in the presence of microwave irradiation. The microwave irradiation of the slurry takes place under process conditions whereby crystalline pyrite may be formed in-situ on surfaces of the chalcopyrite particles. Crystalline pyrite may be formed on surfaces of the chalcopyrite particles from amorphous phase pyrite. Leached copper is recovered from said acidic leach solution. A device for more efficiently leaching a copper bearing sulfide mineral slurry containing chalcopyrite is also described herein.