US 11,692,239 B2
Process and system for plasma-induced selective extraction and recovery of species from a matrix
Frédéric Rousseau, Esclavolles-Lurey (FR); Olivier Lesage, Vitry-sur-Seine (FR); Jonathan Cramer, Paris (FR); Frédéric Prima, Paris (FR); and Daniel Morvan, Paris (FR)
Assigned to Centre National de la Recherche Scientifique (CNRS); and Paris Sciences et Lettres
Appl. No. 16/308,279
Filed by Paris Sciences Et Lettres—Quartier Latin, Paris (FR); and Centre National de la Recherche Scientifique (CNRS), Paris (FR)
PCT Filed Jun. 8, 2017, PCT No. PCT/EP2017/064039
§ 371(c)(1), (2) Date Dec. 7, 2018,
PCT Pub. No. WO2017/211994, PCT Pub. Date Dec. 14, 2017.
Claims priority of application No. 16305687 (EP), filed on Jun. 10, 2016.
Prior Publication US 2019/0136341 A1, May 9, 2019
Int. Cl. C22B 4/00 (2006.01); C22B 4/08 (2006.01); C22B 19/30 (2006.01); C22B 7/00 (2006.01)
CPC C22B 7/004 (2013.01) [C22B 4/005 (2013.01); C22B 4/08 (2013.01); C22B 7/001 (2013.01); C22B 19/30 (2013.01); Y02P 10/20 (2015.11)] 14 Claims
OG exemplary drawing
 
1. A process for extracting a species of a plurality of species from a matrix, comprising:
injecting a plasma into an extraction chamber by a plasma torch, wherein the plasma is formed from a plasma generating gas and an additional gas, the additional gas having a composition selected to react with a chemical composition of the species to be extracted from the matrix;
reacting atoms of the additional gas of the plasma with the species to be extracted to form molecules at a surface of the matrix such that the species is vaporized and extracted from the matrix, the matrix disposed on a moveable support within the extraction chamber;
continuously monitoring a composition of excited elements of the vaporized species extracted from the matrix and contained in the plasma by optical emission spectroscopy;
setting a distance between the moveable support and the plasma torch to achieve a predetermined temperature at an interface between the matrix and the plasma, wherein the predetermined temperature is a function of the species to be extracted from the matrix;
setting the matrix at a determined potential related to the plasma and adjusting the potential according to the monitored excited elements; and
collecting on a plate, exterior to the plasma, the molecules of the species extracted from the matrix.