Process and system for plasma-induced selective extraction and recovery of species from a matrix

A system for selective extraction of species from a matrix, comprising:

• an extraction chamber,
• a support located within the extraction chamber,
• a plasma torch comprising a supply of plasma-producing gas, a supply of at least one additive gas, and a gas mixing device, the plasma torch being configured for generating a plasma directed towards the support,
• an optical emission spectroscopy apparatus configured to continuously monitor excited elements contained within the extraction chamber,
• a control unit operatively coupled to the support and the plasma torch, the control unit configured to:
• determine and modify a distance between the 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;
• and
• modify a composition of the at least one of the plasma-producing gas and the at least one additive gas as a function of a composition of the monitored excited elements such that the species of the plurality of species in the matrix is extracted;
• wherein the support is movable with respect to the plasma torch to change the distance between the support and the plasma torch during the injection of the plasma;
• a power source configured to set the matrix disposed on the support at a determined potential;
• and
• an RF filter interposed between the power source and the matrix.