| Ionic rare earth mine is a unique type of rare earth mine in southern China with diverse partitions. The content of middle rare earths and heavy rare earths are high in particular, which makes them at an irreplaceable place in high-tech areas. There are many disadvantages:the rare earth concentration of ionic rare earth leaching liquid is low, high impurity content, complex composition, long processes. In order to get better gather rare earth leaching liquid rare earth ions, separate the non-rare earth impurities. The method of extracting rare-earth leachate from resin was applied in this paper, the influence of adsorption condition on resin adsorption performance was studied from the selection of resin,(and) the resin adsorption mechanism was also researched,(and) then we determined the optimum adsorption condition of rare-earth leachate by the quadratic orthogonal rotation experiment, finally discussed the adsorption condition of resin combination under the optimum extraction condition and proposed the optimum resin combination.The adsorption and desorption ability of different resin for Nd3+and rare earth ions in leaching liquid was studied, and the relationship between resin types and the adsorption performance was established, the D001,001*8, DH100resins was selected for conducting the further research. In the neodymium chloride solution, the relationship between resin adsorption capacity for Nd3+and adsorption time, pH, temperature, concentration of feed liquid are investigated under using the static adsorption method, The results showed that the adsorption capacity of the three kinds of resin with the increasing of adsorption time also increased, adsorption temperature and the concentration of the feed liquid, while the adsorption capacity reached the maximum when pH=3.5. According to the three factors quadratic orthogonal rotation analysis, the optimal adsorption conditions for neodymium chloride was obtained:T=313Kn pH=3.5、t=586min. Adsorption time is extremely significant influence factors for resin absorption. The penetration curves was measured on the optimal adsorption conditions, the concentration of neodymium chloride is20mmol·L-1, the results showed that the penetration volume increased and adsorption rate decreased with the increasing of adsorption content.Through analysis the thermodynamics and kinetics law of experimental data obtained resin adsorption Nd3+. Calculated:Langmuir isotherm model was more suitable for three kinds of resin adsorption data than freundlieh isothermal. The thermodynamic parameters of adsorption resin was as follows:resin D001△H=13.45KJ·mol-1,△S=53.035J·mol-1-k-1,△G=-2.09KJ·mal-1; resin001*8△H=7.291KJ·mol-1,△S=25.389J·mol-1·k-1,△G=-0.147KJ·moi-1;resin DH100△H=18.58KJ·mol-1,△S=64.97J·mol-1·k-1,△G=-0.78KJ·mol-1; Quasi-second-order kinetic model was the most suitable for the three resin the adsorption process; the activation energy of resin adsorption:resin DH100Ea=17.5909kJ·mol-1, resin D001Ea=31.4701kJ·mol-1, resin001*8Ea=43.4533kJ·mol-1. In the rare earth leaching solution, the adsorption temperature, liquid pH, the dilution factor,the influence of velocity flow to each ion adsorption capacity of the resin were studied. Experimentshowed that the adsorption capacity of the three kinds of resin for RE3+, SiO32-and Al3+increasedwith the increasing of adsorption temperature or dilution ratio, decreased with the increasing of flowrate. While the adsorption capacity of the three kinds of resin for Mg2+increased with the increasingof adsorption temperature, decreased with the increasing of flow rate or dilution ratio. The adsorptioncapacity size of the three kinds of resin for each rare earth ion was: REO>Al>Mg>SI. The effect ofthree resin static and dynamic adsorption separation of rare earths leachate were compared, theresults showed that the dynamic adsorption separation was better than the static adsorption; Theseparation ability of resin001*8was better than resin D001and resin DH100.The second rotation orthogonal experimental datas were analyzed, the dynamic adsorption conditionsoptimal for: pH=3.5of feed solution, diluted to3times, the flow rate was10ml min-1.The resincomposition adsorption were studied under this conditions, five kinds of resin composition can gather99.8%Nd3+from rare earth leaching liquid. Wherein the impurity effect of resin GX-1and001*8resincombination is the best, For SiO32-、Al3+、Mg2+impurity removal rates were：86.1%、63.52%、89.71%,theresincan becompletelydesorbedby1mol L-1hydrochloricacid. |
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