METHOD OF FOAM FLOATATION FOR SEPARATION OF SILICATES AND CARBONATES OF ALKALI EARTH METALS WITH APPLICATION OF COLLECTOR, INCLUDING AT LEAST ONE HYDROPHOBICALLY MODIFIED POLYALKYLENE IMINE Russian patent published in 2015 - IPC B03D1/01 B03D101/02 

FIELD: chemistry.

SUBSTANCE: invention relates to method of separating silicates and carbonates of rare earth metals by foam floatation. Method of separating silicates and carbonates of alkali earth metals includes the following stages: a) preparation of at least one mineral material, including at least one silicate and at least one carbonate of alkali earth metal, with said mineral material having weight average diameter of grains from 5 to 1000 mcm; b) preparation of at least one hydrophobically modified polyalkylene imine; c) contact of said mineral material (materials) from stage a) with said hydrophobically modified polyalkylene imine (polyalkylene imines) from stage b) in one or more stages in water medium to form water suspension with pH equal from 7 to 10; d) passing gas through suspension from stage c); e) regeneration of product, containing alkali earth metal carbonate and silicate-containing product from suspension; f) increase of pH of silicate fraction from stage e) in water medium by at least 0.5 pH unit in order to desorb all or part of hydrophobically modified polyalkylene imine (polyalkylene imines) from silicate fraction and extract hydrophobically modified polyalkylene imine (polyalkylene imines) into washing liquid, and g) processing of liquid fraction from stage f) with acid to reduce said fraction pH by at least 0.5 pH unit. Polyalkylene imine is hydrophobically modified by substitution of all or part of hydrogen atoms of their primary and/or secondary amino groups with functional group R, where R includes linear or branched, or cyclic alkyl- and/or aryl group and contains from 1 to 32 carbon atoms. Modification of polyalkylene imine results in increase of quantity of atomic C relative to non-modified polyalkylene imine, constituting from 1 to 80%. Before modification polyalkylene imine contains at least 3 alkylene imine repeating units and has molecular weight, constituting from 140 to 100000 g/mol.

EFFECT: increased separation efficiency.

26 cl, 13 tbl, 7 ex