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针对地浸采铀浸出液低含量铼的回收,研究了D302-Ⅱ弱碱性阴离子交换树脂吸附和解吸铼的性能和机制。通过静态试验考察温度、酸度、时间对树脂吸附的影响;通过动态试验考察了溶液酸度和流速的影响,并进行了解吸剂及其浓度影响试验、抗干扰试验及树脂再生的试验;用地浸采铀浸出液通过D302-Ⅱ树脂,进行模拟回收铼试验。结果表明,D302-Ⅱ树脂对铼的吸附速率快,吸附反应速率常数k=1.6×10-3s-1,半交换期t1/2=433 s。吸附酸度在pH 2.0～5.0范围内,有利于铼的吸附。吸附平衡服从Freundish吸附等温式,吸附反应放热,反应可在常温下进行。动态上柱酸度选择为pH 2.0～5.0,流速1～2 ml.min-1,铼的吸附率可达95%以上;洗脱液选择NH4OH,25倍树脂床体积的3 mol.L-1NH4OH溶液可将铼洗脱完全。地浸采铀浸出液中的共存离子不影响铼的吸附和解吸,0.5 mol.L-1H2SO4溶液可使树脂再生。树脂对铼的静态和动态吸附容量分别为166和162 mg.g-1干树脂,对浓度低至0.03 mg.L-1铼溶液吸附和解吸,回收率可达96%～102%,表明该树脂有较好的应用前景。
Aiming at the recovery of low content of rhenium in leachate from in situ leaching, the performance and mechanism of rhenium adsorption and desorption by D302-Ⅱ weakly basic anion exchange resin were studied. The effect of temperature, acidity and time on the resin adsorption was investigated by static test. The effect of solution acidity and flow rate was investigated by dynamic test. The effect of desorbent and its concentration, anti-interference test and resin regeneration test were investigated. Uranium leachate passed through D302-II resin and simulated rhenium recovery test. The results showed that the adsorption rate of rhenium on D302-Ⅱ resin was faster, the adsorption rate constant k = 1.6 × 10-3s-1 and the half-exchange period t1 / 2 = 433 s. Adsorption acidity in the pH range of 2.0 to 5.0, is conducive to rhenium adsorption. Adsorption equilibrium following Freundish adsorption isotherm, the adsorption reaction is exothermic, the reaction can be carried out at room temperature. Dynamic column acidity was chosen as pH 2.0-5.0 and flow rate was 1-2 ml · min-1, the adsorption rate of rhenium was more than 95%. The eluent was NH3OH, the volume of 3 times of resin bed was 3mol.L-1NH4OH Rhenium can be eluted completely. Coexisting ions in in-situ leaching uranium leachate did not affect the adsorption and desorption of rhenium. The 0.5 mol.L-1H2SO4 solution regenerated the resin. The static and dynamic adsorption capacity of resin to rhenium were 166 and 162 mg.g-1 dry resin, respectively, and the recoveries of 96% ~ 102% for the rhenium solution with concentration as low as 0.03 mg.L-1 were 96% ~ 102% Resin has good application prospects.