Study On Re-adsorption Phenomena And Mechanisms Of Ion-absorbed Rare Earth Ore

Situation ionic rare earth ore leaching process,there will be re-adsorption rare earth rare earth ore mother liquor of rare earth ions occur,will close when the mother liquor of rare earth ions were reduced or no rare-earth ions.For this phenomenon,the paper Anyuan an ion adsorption type rare earth ore as an object,and then to study the rare earth mine adsorption phenomena and mechanisms,in order to reduce the leaching process of re-adsorption probability,improve the rare earth ore extraction.In the first article of the rare earth ore leaching conditions to take the test,study leaching conditions on the rare earth ore leaching effect situation;identification of the mother liquor,the content of each ion;determining optimum conditions of rare earth ore leaching.On the basis of leaching tests on rare earth ore re-assay of a study the effect of different conditions,factors affecting the situation of rare earth mine re-adsorption,adsorption and then to identify the mother liquor may arise in the mines and the like.In combining theoretical knowledge,a series of experiments and equipment testing and other means of re-adsorption mechanism of analysis and research.Leaching conditions of rare earth ore leaching effects: cream dip the best way,the best effect of ammonium sulfate leaching agent,leaching concentration,leaching dose of liquid to solid ratio of water and the pressure of the top liquid-solid ratio is increased so that an increase or leaching after increasing the lead balance,p H value increased the lead after leaching increases and then decreases.The rare earth ore optimum leaching conditions for leaching to leaching way of leaching,the leaching agent ammonium sulfate,ammonium sulfate concentration of 2%,the amount of ammonium sulfate liquid to solid ratio of 0.7:1,top water liquid to solid ratio of 0.4:1,p H value selected between 4-5.Then assay showed that the mother liquor in contact with the rare earth ore more fully re-adsorption,the better;rare earth ion concentration or the mother liquor of liquid to solid ratio increases its rare earth mine and then the greater the adsorption capacity;will the mother liquor cation ion exchange capacity greater than rare earth ions inhibiting its re-absorption,a small exchange capacity will promote re-adsorption;p H value increased again after adsorption capacity then decreases.Under the same conditions,the re-adsorption rare earth mine saturation greater the amount of re-adsorbed better.Re-adsorption capacity: Total Weathered mine <weathered ore<weathered tailings <whole weathered tailings.Rare earth mine in the adsorption process is an exothermic process,or spontaneous process.The rate of re-adsorption rare earth ions rapidly cooling beneficial to the re-adsorption.Re-adsorption rare earth minerals belong to the diffusion controlled kinetic equation: 1-2a / 3-(1-a)2/3 = Kt(a for the re-adsorption rate,K is the number of rate constants under different conditions).Ionic rare earth ore re-adsorption is physical adsorption,rare earth ore and then the Langmuir adsorption isotherm equation.Infrared spectrum change before and after the re-adsorption of rare earth ore,no new peaks were observed to produce,after re-adsorption mineral surface without generating a new substance,and then the surface adsorption of rare earth minerals will not change.