Gravity Separation & Concentration Methods

Depends a little on the source of the ceramic powders, but it sounds like you are processing a spent catalyst. But the general (simplified) process would be first to burn off any carbon residue on the surface in a high temperature calcination stage (either a rotary kiln (direct fire) or rotary calciner (in direct fire)), then pulverize or grind the material followed by a series of hydrometallurgical steps (leaching and electrowinning) to produce the metals. Then there is the sludge processing to dry and dispose of the main carrier material (probably 90+% of the material).

Do to many unknown variables, answering your last question ("How well will the concentrator perform?") is impossible to answer.  The processes take some experience to operate well.  In addition water quality plays a big part in performance.  The only way to know is to first do lab tests and then scale up.  But only having a metric tonne makes this difficult as that is close to the volume a reputable lab would need to perform any reliable tests.

Unfortunately this is one of the major hurdles electronic recycling hits, local volumes amke efficent processing very, very dificult.