Patent ID: 7297278

Claim:
A method of filtering metal components from a colloidal suspension or solution comprising: placing the colloidal suspension or solution in a vessel, where the colloidal suspension or solution comprises a liquid and a metal component where the metal in the metal component is selected from the group consisting of metals with an atomic number greater than 10, and further comprises a metal precipitator selected from the group consisting of iron salts, aluminum salts, potassium salts, sodium salts, copper salts, metal sulfides, and metal hydroxides and mixtures thereof; and providing a leaf element in contact with the colloidal suspension or solution in the vessel, the leaf element comprising a membrane having an exterior surface and an interior surface, where the membrane is impermeable to the metal component of the colloidal suspension or solution, and the leaf element further comprises a support mounted at the interior surface of the membrane and sealed within the membrane; and in any order or concurrently: vibrating the leaf element tangentially relative to the exterior surface of the membrane to induce shearing between the exterior surface of the membrane and the colloidal suspension or solution; and applying a negative and/or positive pressure to the leaf element to urge permeation of the membrane by a purified liquid of the colloidal suspension or solution.