Study On The Crystal Chemistry, Surface Characteristics And Flotation Behavior Between Rhodochrosite And Calcium-magnesium Carbonate Minerals

The main mineral components of manganese carbonate ore are rhodochrosite and calcium magnesium carbonate,which have similar crystal structure and surface properties,as well as mineral floating properties.The separation of similar carbonate minerals has become a difficult point in the flotation separation of manganese carbonate ore.In this paper,through systematic study of the crystal structure,surface properties and flotation behavior of rhodochrosite,magnesite and calcite,and the relationships among them are summarized,so as to provide basic theory for solving the flotation difficulties in separation of manganese carbonate ore.The main research results of this paper are as follows:The crystal structure and surface properties of the three carbonate minerals are similar.Due to the different metal cations radius,the chemical bonds and structural parameters of the mineral crystal structure are different.the newly formed mineral surface are mainly along the fracture direction of m-o ionic bonds with weak bond strength,and there have different amounts of M,C and O elements.These small differences determine the mineral surface properties?surface electrical properties,relative concentration of metal atoms,solubility,etc.?are differences.Through the slight difference in crystal structure and surface properties,it is predicted that by adding certain agents or other means to change the surface properties of minerals,expected to increase the floatability difference between rhodochrosite and calcium-magnesium carbonate.Under the single mineral flotation system,the four collectors are almost non-selective;after the addition of the inhibitor,the mineral flotation behavior becomes larger,sodium hexametaphosphate,sodium lignosulfonate and Dextrin has a good inhibitory effect on rhodochrosite,magnesite and calcite.The inhibition of citric acid,CMC,hydroxypropyl starch ether and pectin calcite is strong,but it also inhibits rhodochrosite or magnesite,water.The selection inhibition effect of glass and tannin is relatively poor;metal cations show similar rules for the change of mineral flotation behavior.Sodium oleate is chemically adsorbed on the surface of the rhodochrosite,while dodecylamine is mainly physically adsorbed.The inhibitory effect of sodium hexametaphosphate is to form chelates with Ca²⁺ions on the surface,dissolve the chelates from the mineral surface,and reduce the concentration of active particles on the calcite surface;Sodium lignosulfonate can chelate the Mn²⁺ions on the surface of rhodochrosite to form a stable chelate;It is speculated that dextrin can be chemically adsorbed on the rhodochrosite hydroxylated surface film,while the hydrophilic group of dextrin itself forms the hydrophilic film on the mineral surface;Metal ions in solution may change the surface electrical properties of minerals,form metal salt precipitation with oleate,precipitate on the surface of minerals in the form of hydroxide or carbonate,thus changing the flotation behavior of minerals.