Study On The Mechanism Of Action Of Flotation Reagents On The Surface Of Calcium-magnesium Phosphate Or

The complex crystal structure of calcium-containing minerals such as dolomite and apatite,with similar surface chemistry,can easily undergo surface transformation during flotation,making it difficult to separate them effectively using traditional fatty acid-based trapping agents.In this study,the flotation behaviour of two minerals before and after the action of fatty acid-based agents under different conditions was systematically investigated using the trap sodium oleate（Na Ol）and a new fatty acid-based agent（GJBW）and a new inhibitor polyaspartic acid（PASP）;and the mechanism of agent action on the mineral surface was studied through a series of surface chemical tests and flotation solution chemical calculations.This study is a guide to the development and utilisation of calcium and magnesium phosphate ores.The findings and conclusions of the study are as follows.1.The flotation experiments revealed that GJBW had a larger impact on dolomite in an acidic solution than that of Na Ol.After adding 10 mg/L of GJBW,the amount of P₂O₅ in the flotation concentrate of mixed ore was 31.54 percent,which was 4.95 percent higher than that of Na Ol,and the recovery of P₂O₅ was 86.12percent,which was 3.43 percent higher than that of Na Ol.GJBW has an excellent flotation index when employed as a collector in artificial mixed ore and calcium-magnesium phosphate ore flotation.2.Under acidic conditions,GJBW produces a higher heat of adsorption on the surface of dolomite than Na Ol,significantly increasing the hydrophobicity of dolomite.The surface characterization,zeta potential,and flotation solution chemistry results indicate that GJBW could ionize more RCOO^-and H（RCOO）^2-ions,which interact strongly chemically with the large number of metal active sites exposed on the dolomite surface,forming uniform,dense spot adsorption on the dolomite surface and promoting effective flotation separation of dolomite and apatite in the H₃PO₄system.3.Under Polyaspartic acid conditions,it has been discovered that a large number of carboxylic acid groups ionized by PASP selectively chelate with magnesium ions on the dolomite surface,influenced by the spatial inhibition and repulsion of local anions,which adsorb onto the dolomite surface.PASP inhibited further Na Ol adsorption on the dolomite surface,reducing dolomite floatability and eventually achieving flotation separation of the two minerals under Polyaspartic acid conditions.