提高钼冶炼废酸中钼离子交换吸附性能的研究

Method for Improving Ion-Exchange Adsorption Performance of Mo in Spraying Water

开展了采用石灰适度中和的方法,改善钼冶炼废酸中钼吸附性能的研究。主要进行了石灰加入量、反应温度、反应时间等预处理条件试验,对滤渣的组成进行了X射线衍射仪(XRD)表征,并对预处理前后的钼冶炼废酸进行了静态、动态吸附试验。试验结果表明:石灰加入量小于75 g·L^(-1)条件下,预处理过程钼铼损失率较低; CaO加入量为50 g·L^(-1),反应温度25℃,反应时间100 min条件下,废酸中硫、氟和硅的脱除率分别为66.16%, 0.21%和9.65%,相比于未处理废酸,上述条件下预处理后废酸进行离子交换吸附时,铼的静态平衡吸附容量从11.36 mg·ml^(-1)提高到13.53 mg·ml^(-1),钼的静态平衡吸附容量由20.25 mg·ml^(-1)提高到147.63 mg·ml^(-1);采用D314树脂在1 BVs流速下对钼进行动态吸附,处理液量在120 BV时,C/C_0=0.3,吸附效果较好;采用10%的氨水溶液在0.5 BVs流速下解吸附,解吸液含钼39.25 g·L^(-1),钼得到有效富集。

Research on improving the ion-exchange adsorption performance of Mo in spraying water by moderate neutralization method was discussed,additionally lime was used as neutralizing agent.A series of experiments were done at different condition of lime amount,reaction temperature and reaction time etc.The residues were characterized by X-ray diffraction(XRD).The spraying water before and after pretreatment by lime was used for adsorption experiments respectively and the differences of ion-exchange performance of Mo was compared.Results showed loss ratio of Re and Mo in pretreatment process was very low when the lime amount added in the spraying water was less than 75 g·L^-1.In the pretreatment process the removal rate of S,F and Si was 66.16%,0.21%and 9.65%respectively under the optimum conditions including lime amount of 50 g·L^-1,reaction temperature of 25℃,reaction time of 100 min.At the same experimental conditions,the static equilibrium adsorption capacity of Re was increased from 11.36 to 13.53 mg·ml^-1 and the static equilibrium adsorption capacity of Mo was increased from 20.25 to 147.63 mg·ml^-1,when the resin was put in the spraying water after pretreatment.The dynamic adsorption experiments,D314 resin was used as adsorbent and the flow rate was 1 BV·h^-1,showed that C/C 0=0.3 when the volume of effluent was 120 BV,which meant that the absorbing effect of Mo was satisfied.Desorption solution,in which the content of Mo was 39.25 g·L^-1,was gained by the condition that the eluting agent of 10%ammonia,flow rate of 0.5 BV·h^-1.Mo in the spraying water was enriched effectively.