Agents and processes for the separation of mixtures of solids

摘要

Agents and processes are proposed for the separation of mixtures of solids, permitting mixtures of substances having components of differing density to be divided into their individual constituents rapidly, with low expenditure and virtually quantitatively. The separating agents used are solutions of metatungstates of differing concentration having densities up to 3.1 g cm<-3>. The process can be carried out either statically, that is using the earth's gravitational field, or using suitable centrifugal accelerations. Dense media of appropriate particle size can also be added as separating agents to the metatungstate solutions. Sodium metatungstate suspensions containing tungsten carbide, for example, give densities of 4.6 g cm<-3>.