The reaction of chelate-forming reagents with minerals under flotation conditions

Abstract

Despite the extensive use of chelate-forming reagents, flotation specialists have not yet obtained definite information on the composition and structure of the surface compounds formed during adsorption of the reagents on minerals. However, this theoretical problem has now become of great practical importance in connection with the development of the principles of direct selection and synthesis of flotation reagents with given properties.To develop selective flotation reagents, we can put to good use the experience gained in the neighboring regions of use of chelate-forming reagents (extraction, precipitation, etc.). Such an approach is based on the assumption that the laws of formation of the chelate ring during the reaction of chelate-forming reagents with metals in a solution and with mineral surfaces are the same [i]. Direct proof of this would give a sound theoretical basis for the postulated and present-day principles of selective flotation reagent selection [2, 3].Research by Solozhenkin [4, 5] is therefore of great interest; using the ESR method he investigated the structure of the products of reaction of sulfhydryl reagents with the surfaces of nonferrous metal sulfides.In particular, he established that when particles of Cu(ll)-activated chalcopyrite and other sulfides are previously floated with sodium diethyldithiocarbaminate (Na-DEDC), copper (II) bis-(dlethyldithiocarbaminate) passes into the solvent: S IS