Patent ID: 6635180
Filing Date: 2003-10-21
Classification: B01D,C01G,C22B,Y02P

Abstract:
A process for purifying and treating a suspension having a material being 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 being selected from the group consisting of a solid, a precipitate, dissolved, and any combinations thereof, the process comprising:concentrating the material in the suspension using a membrane filter apparatus by removing a liquid in a form of a filtrate from the suspension to obtain a concentrated suspension, wherein said filtrate has a material selected from the group consisting of a dissolved impurity, a precious material, and any combinations 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 the form of said filtrate using said membrane filter apparatus such that a concentration of the material 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 draining said membrane filter apparatus, wherein the material is provided in a purified form.