Mass separator with controlled input

A device for separating a multi-constituent material into constituents, said device comprising:

• a cylindrical wall having an inner radius, Rwall, said wall surrounding a chamber and defining a longitudinal axis;
• means for converting the multi-constituent material into a multi-species plasma in said chamber within a radius, rsource, from said longitudinal axis to create ions of relatively low mass to charge ratio, M1, and ions of relatively high mass to charge ratio, M2;
• a collector shaped as a hollow cylinder having outer radius Router, said collector centered on said longitudinal axis and positioned at said second end of said wall;
• means for establishing a radial electric field (Er) and an axially aligned magnetic field (Bz) in said chamber to create a plasma region of radius, a, from said axis, with a<Rwall;
• and
• means for controlling said electric field (Er) and said magnetic field (Bz) to place said ions of relatively high mass to charge ratio, M2, on trajectories into said collector, and to place said ions of relatively low mass to charge ratio, M1, on trajectories through said hollow collector.

A method for separating a multi-constituent material into constituents, said method comprising the steps of:

• providing a cylindrical wall having inner radius, Rwall, said wall surrounding a chamber and defining a longitudinal axis;
• converting the multi-constituent material into a multi-species plasma in said chamber within a radius, rsource, from said longitudinal axis to create cold ions of relatively low mass to charge ratio, M1, and cold ions of relatively high mass to charge ratio, M2;
• centering a hollow cylinder having an outer radius, Router, on said longitudinal axis;
• establishing crossed electric and magnetic fields (E×B) in said chamber to define a cutoff mass, MC, relative to a radial distance, a, from said axis, with M1<M2≦MC and a<Rwall;
• and
• controlling E×B to place said ions of relatively high mass to charge ratio, M2, on trajectories having a radial apogee, rapogee, into said cylinder with rapogee>Router, and to place said ions of relatively low mass to charge ratio, M1, on trajectories through said hollow cylinder.