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Vanadium is a rare high-melting metal , and dissolved in acid or alkali . Vanadium often in the leaching solution to pentavalent vanadium anion forms exist group interchanged , with an anion exchange resin , while separated from the other impurities . This article the D201 resin adsorption vanadium , phosphorus , silicon , and its adsorption properties and mechanism . The research findings are as follows : single element aqueous systems , the D201 resin exchange vanadium , phosphorus , silicon adsorption by the pH, the amount of resin , time , temperature factors . pH = 1.9-2.1 , resin adsorption of vanadium best related to the mode of occurrence in the solution , adsorption equilibrium time of 11h ; phosphorus at pH = 6.9-7.1 , the adsorption of the best , adsorption equilibrium time of 30 min ; silicon the best adsorption equilibrium time 40 min in pH = 11.4-11.6 adsorption . Warming the resin adsorption vanadium , phosphorus favorable benefit of low temperature on the adsorption of silicon . Multi-element the mixed analog aqueous solution system , phosphorus and silicon resin adsorption vanadium , and therefore does not require pre- impurity . PH = 1.9-2.1 , the separation factor of the vanadium - phosphorus and vanadium silicon were 48.33 and 106.77 . Actual system dynamic adsorption and desorption experiments show that the adsorption the flow rate of the feed solution should be ≤ 2BV / h, the desorption flow rate should be controlled between 2-3BV / h , 5% NaOH 10% NaCl do desorbent can D201 resin vanadium, phosphorus, silicon is substantially completely desorbed. The Thermodynamic Studies show that of D201 resin Langmuir or Freundlich isotherm equation to describe the adsorption behavior of vanadium , phosphorus , silicon can be used . D201 Resin for vanadium, phosphorus, silicon and the adsorption process is a spontaneous process (△ G LT ; 0 ) , the entropy becomes a positive value (△ S GT ; 0) . D201 resin adsorption vanadium, phosphorus is an endothermic process (△ H GT ; 0 ) , the adsorbed silicon is an exothermic process ( △ H LT ; 0) . Kinetic studies showed that D201 resin adsorption of vanadium , phosphorus , silicon exchange process in line with the two adsorption exchange kinetics . Moving boundary model simulation and stirring speed , resin particle size tests show that D201 resin microspheres diffusion-controlled adsorption of vanadium , phosphorus , and the proliferation of joint control by the proliferation of microspheres and macroporous silicon adsorption .
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