Separation of Aluminum Glass and Plastic Using Fluids - Essay Example

The paper discusses alkali metal salt or an alkaline earth metal salt of metatungstate. The solution should have a concentration of 1 to 80. The oxidant used is preferably selected from any of the following dichromate, chromate, nitrate, permanganate, peracid, and pester groups (Allies & Pagenkopf, 1998). These should have a preferred concentration of 0.05 to 0.5 weight %.

The preferred alkaline salts are salts of lithium or sodium namely sodium dihydrogendodecawolframate or lithium dihydrogendodecawolframate. However, sodium dihydrogendodecawolframate is preferentially used. According to the invention bringing the solid mixture into contact with the separating liquid is advantageous. These liquids should be of differing densities in gradations of 0.005 g/cm.sup.3 to 0.1 g/cm.sup.3, preferably 0.05 g/cm.sup.3 to 0.01 g/cm.sup.3 (Jody, Daniels & Pomykala , 2003).Within a selected region of the density range the sinking solid component is removed after each stage.

Besides this solution, other solutions that have been used in the separation of mixtures include ethanol or solutions containing ethanol, Ca(NO 3) 2, CaCl 2 ZnCl 2, or NaCl. All these methods rely on the relative buoyancy of the separating material.