Uranium and thorium adsorption from aqueous solution using a novel polyhydroxyethylmethacrylate-pumice composite
Uranium and thorium adsorption from aqueous solution using a novel polyhydroxyethylmethacrylate-pumice composite
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DOI：
10.1016/j.jenvrad.2012.11.015
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发表时间：
2013-06-01
影响因子：
2.3
通讯作者：
Akkaya, Recep
中科院分区：
文献类型：
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作者：
Akkaya, Recep
在水溶液中采用自由基聚合法制备了聚甲基丙烯酸羟乙酯-浮石[P(HEMA-Pum)]复合材料。考察了P（HEMA-Pum）复合材料对UO22+和Th4+的吸附特性，考察了pH、浓度、时间（动力学）、温度（热力学）、离子强度和选择性等参数，并根据所得结果得出了相关参数。这些结果表明，所有吸附剂对铀和钍离子都有很高的亲和力。Langmuir、Freundlich和Dubinin-Radsushkevich模型得到的参数与数据拟合得很好。焓变和熵变结果表明，整个吸附过程为吸热（δ H > 0）和熵增（δ S > 0），吸附过程为自发（δ G < 0）。吸附动力学符合拟二级模型，表明控制速率的步骤是通过离子交换过程发生的化学吸附。对P（HEMA-Pum）的可重复使用性进行了研究，发现该复合材料至少可重复使用5次。(c) 2012 Elsevier Ltd.版权所有。
Poly(hydroxyethylmethacrylate-pumice), [P(HEMA-Pum)], composite was synthesized by free radical polymerization in aqueous solution. The adsorptive features of P(HEMA-Pum) composite were investigated for UO22+ and Th4+ using a range of pH, concentration, time (kinetics), temperature (thermodynamics), ionic strength and selectivity, and the related parameters were derived from the obtained results. These results indicated that all adsorbents had high affinity to the uranium and thorium ions. The parameters obtained from Langmuir, Freundlich and Dubinin-Radsushkevich models fit the data well. The values of enthalpy and entropy changes showed that the overall adsorption process was endothermic (Delta H > 0) and increasing entropy (Delta S > 0), and it was spontaneous (Delta G < 0) as expected. The adsorption kinetics following the pseudo-second order model indicated that the rate-controlling step was chemical adsorption that occurred by ion exchange process. Reusability of P(HEMA-Pum) was also investigated, and it was found that the composite could be used at least 5 times. (c) 2012 Elsevier Ltd. All rights reserved.