Process and apparatus for the purification and/or treatment of suspensions

An apparatus for purifying and treating a suspension having a material selected from the group consisting of one or more rare earth materials, one or more precious metals, an impurity, and any combinations thereof, wherein the material is in a form selected from the group consisting of a precipitate, a solid, dissolved, and any combinations thereof, the apparatus comprising:

• a reservoir being fluidly connected to a membrane filter apparatus, said membrane filter apparatus for concentrating the material in the suspension by removing a liquid in a form of a filtrate from the suspension to obtain a concentrated suspension, wherein said filtrate has the material selected from the group consisting of a dissolved impurity, a precious metal, and any combination thereof;
• a wash liquid dispensing apparatus adapted to dispense a wash liquid in an aqueous solution in the suspension in said reservoir, said wash liquid having a predetermined chemical action with the material, said wash liquid being one selected from the group consisting of an acetic acid, an ammonium nitrate, a sodium carbonate, a sodium bicarbonate, a hyrdochloric acid, a nitric acid, an aqua regia, and any combinations thereof;
• said membrane filter apparatus removing said wash liquid in the form of said filtrate such that a concentration of the material being in the solid form or in the precipitate form is essentially not changed and a concentration of the material in the dissolved form is reduced to a predetermined value;
• and
• means for draining said membrane filter apparatus to provide the solid or precipitate material in a purified form.

A method of purifying and treating a suspension having a material in the suspension comprising:

• concentrating the material in the suspension using a membrane filter apparatus by removing a filtrate to obtain a concentrated suspension, wherein said filtrate has the material selected from the group consisting of a dissolved impurity, a precious material, and any combination thereof;
• washing said concentrated suspension by adding an amount of a wash liquid that is an aqueous solution having a predetermined chemical action with the material, said wash liquid being selected from the group consisting of an acetic acid, an ammonium nitrate, a sodium carbonate, a sodium bicarbonate, a hydrochloric acid, a nitric acid, an aqua regia, and any combinations thereof;
• removing said wash liquid in a form of said filtrate using said membrane filter apparatus such that a concentration of the material in a solid form or in a precipitate form in said concentrated suspension is substantially unchanged and such that the material being in a dissolved form is reduced to a predetermined value;
• draining said membrane filter apparatus to provide the solid or precipitate material in a purified form, said material being selected from the group consisting of gold, platinum, rhodium, palladium, ruthenium, iridium, osmium, cobalt, europium, lanthanum, germanium, gallium, cerium, tantalum, niobium, selenium, tellurium, cadmium, bismuth, beryllium, uranium, manganese, and any combinations thereof.