| 摘要 |
<p>PCT No. PCT/DE94/00313 Sec. 371 Date Aug. 9, 1995 Sec. 102(e) Date Aug. 9, 1995 PCT Filed Mar. 17, 1994 PCT Pub. No. WO94/21382 PCT Pub. Date Sep. 29, 1994A process for separating mixtures of solids of different density, uses a separating liquid and a device for implementing the process. The process is especially suitable for the analysis and technical preparation of waste plastics, glass and electrical scrap. In the process, a reduced mixture of solids with a particle size of 0.1 to 80 mm are brought successively into contact with solutions of separating liquids of differing density in steps of 0.005 to 0.1 g/cm3 within a selected range from that between 0.8 and 2.9 g/cm3 and the floating or sinking solid components are separated after each step. The separating liquid in the density range between 1 and 2.9 is preferably an aqueous solution of an alkali metal salt or an alkaline earth metal salt of metatungstate with a concentration in the range 1 to 80 weight % and an oxidant selected from the chromate, dichromate, permanganate, nitrate, peracid and perester group with a concentration of 0.05 to 0.5 weight %.</p> |
