亲水型偕胺肟吸附剂的ARGET-ATRP可控制备及其对铀的吸附性能

Controlled Preparation of Hydrophilic Amidoxime Adsorbent by ARGET-ATRP and Its Adsorption Performance to Uranium

吸附剂的制备是海水提铀的关键。本文以聚氯乙烯(PVC)为基材,采用电子转移活化再生原子转移自由基聚合(ARGET-ATRP)方法在PVC上引入偕胺肟(AO)和丙烯酸叔丁酯(tBA)基团,合成了偕胺肟基纤维吸附剂(PVC-AO-tBA)。在不同温度、铀溶液浓度和pH值条件下进行了PVC-AO-tBA吸附铀的实验研究,探讨了亲水单体tBA的引入对AO吸附剂吸铀性能的影响。结果表明,在同等条件下,PVC-AOtBA对铀的吸附量由PVC-AO的109mg/g提高到170mg/g;PVC-AO-tBA对酸碱度的适应范围更宽,最佳pH值由6扩展到4~6。动力学分析结果表明,吸附速率也有了明显上升。值得注意的是,在与海水酸碱度接近的弱碱性环境下,平衡吸附量由39mg/g提高到71mg/g,可见吸附效果得到明显提升。

The preparation of adsorbent is the key to the extraction uranium from sea-water.In this paper,amidoxime(AO)and tBA were grafted onto the polyvinyl chloride(PVC)substrate by electron transfer activated regeneration atom transfer radical polymerization(ARGET-ATRP)method to form PVC-AO-tBA.The effects of the introduction of hydrophilic monomer of tBA on the properties of AO adsorbent were investigated by experimental study at different temperatures,uranium solution concentrations and pH.The results show that under the same conditions,the adsorption capacity of uranium on PVC-AO-tBA increases from 109 mg/g to 170 mg/g;the adaptability of the adsorbent to pH is stronger,and the optimum pH of extraction uranium extends from 6 to 4-6.The kinetics analysis shows that the adsorption rate also increases significantly.