	US 12,258,672 B2
	Selective sulfidation and desulfidation
Antoine Allanore, Brentwood, NH (US); and Caspar R. Stinn, Magnolia, TX (US)
Assigned to Massachusetts Institute of Technology, Cambridge, MA (US)
Filed by Massachusetts Institute of Technology, Cambridge, MA (US)
Filed on Dec. 27, 2020, as Appl. No. 17/134,429.
Claims priority of provisional application 62/982,373, filed on Feb. 27, 2020.
Prior Publication US 2021/0277531 A1, Sep. 9, 2021
Int. Cl. C22B 1/06 (2006.01); C22B 1/11 (2006.01); C22B 26/20 (2006.01); C22B 59/00 (2006.01); C25C 3/02 (2006.01); C25C 3/34 (2006.01)

CPC C25C 3/02 (2013.01) [C22B 1/06 (2013.01); C22B 1/11 (2013.01); C22B 26/20 (2013.01); C22B 59/00 (2013.01); C25C 3/34 (2013.01)]

20 Claims

1. A process for selective sulfidation of a target metal compound of a feedstock material within a reactor, the target metal compound consisting of a metal oxide, oxysulfide, carbonate, sulfate, or sulfide, the process comprising:

introducing a flow of sulfur-containing gas into the reactor through a gas inlet of the reactor; and

passing the flow of sulfur-containing gas through the feedstock material within the reactor while controlling a roasting atmosphere in the reactor about the feedstock material including at least a process temperature and a ratio of sulfur to sulfur dioxide chosen for selective sulfidation of the target component to produce a selectively sulfidized compound including a sulfate, oxysulfide, or sulfide of the target metal, the ratio of sulfur to sulfur dioxide being maintained above a predetermined critical ratio for such selective sulfidation of the target metal compound.