Study On Aluminum Removal Process Of Rare Earth Solution With High Aluminum Content

Ion-adsorption rare earth minerals have been discovered for the first time since 1969.The research on the high content of aluminum elements and the great influence on the subsequent production of rare earths has never stopped.However,there are some defects in the aluminum removal technology.In this paper,the process of removing aluminum from the rare earth feed liquid was studied.The process of separating rare earth and aluminum by rare earth trisodium phosphate precipitation was proposed.Selective complexation precipitation aluminum removal process from Rare Earth solution using 8-Hydroxyquinoline and Cyclohexanecarboxylic acid.Adsorption process of 5-sulfonic acid salicylic acid-D290 type anion exchange resin for adsorption of aluminum and 3,5-dinitrosalicylic acid chemically bonded silica gel.(1)The process of separating rare earth and aluminum by precipitating rare earth with trisodium phosphate was studied.it is proved that the precipitation of aluminum phosphate is difficult to occur when the pH is lower than 1.5 by OLI simulation software.The influences of solution pH,reaction time and addition amount of trisodium phosphate on the effect of separating rare earth and aluminum were investigated.The results showed that when the solution pH=1 and the reaction time was 5 minutes,the amount of tri sodium phosphate added was the same as the amount of rare earth substances in the solution.Tthe precipitation rate of rare earth was 93.15%and the precipitation rate of aluminum ion hardly lose.The results demonstrate that the product is mainly a rare earth phosphate.(2)Study on 8-hydroxyquinoline and cyclohexanecarboxylic acid selective complexation precipitation to remove aluminum from the rare earth material solution The main purpose was to investigate the amount of 8-hydroxyquinoline or cyclohexanecarboxylic acid,reaction time,reaction temperature,and solution pH.The effect of complex precipitation on aluminum removal was as follows:? the 8-hydroxyquinoline as a complexing precipitant,the amount of 8-hydroxyquinoline was 1.25 times the theoretical complete reaction amount,the reaction time of constant temperature stirring was 10 minutes,and the reaction temperature was When the final pH of the solution is adjusted to 4.5 at 60?,the removal rate of aluminum ions reaches 94.39%,and the rare earth loss rate is only 8.21%.? Cyclohexanoic acid was used as a complexing precipitant.The removal rate of aluminum ions was achieved when the amount of cyclohexanecarboxylic acid was 1.5 times the theoretical complete reaction amount,the stirring time was 10 minutes at constant temperature,the reaction temperature was 30?,and the final pH of the solution was adjusted to 3.5.It reached 96.74%and the rare earth loss rate was only 1.01%.Both complex precipitants can better achieve the removal of aluminum in the rare earth feed solution.Among them,the aluminum removal efficiency of cyclohexanoic acid is higher than that of 8-hydroxyquinoline,but the aluminum product of 8-hydroxyquinoline is 8-hydroxyquinoline aluminum.It is a widely used photoelectric material with high economic value,so both methods have their own advantages.(3)Study on Adsorption Process of Aluminum Removal by 5-sulfosalicylic Acid-D290 Anion Exchange Resin.Ultraviolet spectrophotometry was used to study the coordination reaction of 5-sulfosalicylic acid with aluminum ions.The results showed that the coordination ratio of 5-sulfosalicylic acid with aluminum ions was 1:1.The adsorption kinetics of aluminum ions by 5-sulfosalicylic acid-D290 resin shows that the adsorption of aluminum ions conforms to the kinetic model of secondary adsorption.The effects of pH,5-sulfosalicylic acid,and the amount of D290 anion exchange resin on the effect of adsorption and removal of aluminum were investigated.The results showed that:in the solution pH = 3.5,the ratio of 5-sulfosalicylic acid to aluminum was 1.5:1,and 20 g of D290 resin was added to the column to adsorb the solution at a flow rate of 0.2 ml/min.The aluminum removal rate reached 75.63%,and the rare earth loss rate was less than 5%.(4)Study on Adsorption of Aluminum on Chemically Bonded Silica Gel of 3,5-dinitrosalicylic Acid.Ultraviolet spectrophotometry was used to prove that the coordination ratio of 3,5-dinitrosalicylic acid to aluminum ion was 1:1,and kinetic studies showed that the adsorption of aluminum ion conformed to the kinetic model of secondary adsorption.The study on adsorption of aluminum by chemically bonded silica gel with 3,5-dinitrosalicylic acid showed that when the pH of the solution was 3.5 and the amount of 3,5-dinitrosalicylic acid was 2 g,the removal rate of aluminum ions in the solution was up to More than 90%,lanthanum ion hardly lose.Therefore,3,5-dinitrosalicylic acid chemically bonded silica can effectively remove trace amounts of aluminum ions in the rare earth material solution,and obtain a highly purified rare earth material solution.The research of this subject has proposed a variety of new research ideas for the rare earth aluminum removal technology.The process of separating aluminum ions by trisodium phosphate precipitation rare earth has the advantages of simple operation and reduced processing steps.Selective precipitation of complexing agent to remove aluminum has the advantages of good selectivity and rapid removal of aluminum.The organic ligands and D290 anion exchange resin co-action adsorption aluminum removal process and 3,5-dinitrosalicylic acid chemically bonded silica adsorption aluminum removal process provides new development idea for the continuous removal of aluminum ions in rare earth materials.The Four kinds of aluminum removal processes all have their own advantages and are suitable for removing aluminum under different production conditions and process requirements.