National Commission of Atomic Energy, Av. General Paz 1499, 1650, San Martín, Buenos Aires, Argentina.
National University of General San Martín, M. Irigoyen 1300, 1650, San Martin, Buenos Aires, Argentina.
Environ Sci Pollut Res Int. 2018 Aug;25(22):21982-21992. doi: 10.1007/s11356-018-2283-9. Epub 2018 May 24.
Perlite is an abundant mineral that requires minimum processing before use either as raw or expanded perlite, resulting in a low-cost, natural porous material. The application of materials for the removal of radioactive cesium from liquid effluents and contaminated waters is currently of great interest. Perlite has been evaluated in the last years for the sorption of a variety of metals, but it had not been investigated before for removal of Cs from contaminated waters. The present work examines the use of perlites from a deposit in Salta, Argentina, for removal of Cs from aqueous solutions. The mineral was characterized by means of powder X-ray diffraction, thermal analysis, analysis of specific area, and scanning electron microscopy. The effect of solution pH, presence of concomitant ions, contact time, Cs initial concentration, perlite dose, and basic or acidic treatment of the sorbent were studied by batch experiments. Removal increased at high pHs and after treatment with NaOH. Sorption of Cs by perlite presented a rapid rise in the first 80 min of contact. The selected material (from Pava mine) yielded removal efficiencies of 84 and 89% before and after treatment with NaOH, respectively, for a dose of 30 g perlite/L and initial cation concentration of 10 mg/L. Our results demonstrate that perlite is a material capable of removing Cs from aqueous solutions, even when applied at low doses. These findings are relevant in the context of removal of radioactive Cs isotopes from nuclear effluents and in case of contamination of environmental waters.
珍珠岩是一种丰富的矿物质，在用作原始或膨胀珍珠岩之前，只需进行最少的加工，因此是一种低成本的天然多孔材料。目前，人们对将材料应用于从液体废水中去除放射性铯和受污染的水非常感兴趣。近年来，珍珠岩已被评估用于吸附各种金属，但之前尚未研究过其从受污染的水中去除铯的能力。本工作研究了阿根廷萨尔塔矿床的珍珠岩用于从水溶液中去除铯的用途。通过粉末 X 射线衍射、热分析、比表面积分析和扫描电子显微镜对矿物进行了表征。通过批量实验研究了溶液 pH 值、共存离子的存在、接触时间、铯初始浓度、珍珠岩剂量以及吸附剂的碱性或酸性处理对去除效果的影响。在高 pH 值下和经 NaOH 处理后，去除效果增加。珍珠岩对 Cs 的吸附在接触的最初 80 分钟内迅速增加。选择的材料（来自 Pava 矿）在未经 NaOH 处理和经 NaOH 处理后的剂量为 30 g 珍珠岩/L 和初始阳离子浓度为 10 mg/L 时，去除效率分别为 84%和 89%。我们的结果表明，即使在低剂量下，珍珠岩也是一种能够从水溶液中去除 Cs 的材料。这些发现对于从核废水中去除放射性 Cs 同位素以及在环境水受到污染的情况下去除 Cs 同位素具有重要意义。
