The effect of cationic surfactants on improving natural clinoptilolite for the flotation of cesium.
The effect of cationic surfactants on improving natural clinoptilolite for the flotation of cesium.
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DOI：
10.1016/j.jhazmat.2020.123567
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发表时间：
2020-07
影响因子：
13.6
通讯作者：
Muhammad Yusuf Prajitno;S. Tangparitkul;Huagui Zhang;D. Harbottle;T. Hunter
中科院分区：
文献类型：
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作者：
Muhammad Yusuf Prajitno;S. Tangparitkul;Huagui Zhang;D. Harbottle;T. Hunter
阳离子表面活性剂浮选是一种用于斜发沸石离子交换树脂脱水的快速分离技术，用于去污核废料废水中的放射性铯离子(Cs+)。初步的动力学和平衡吸附研究表明，细粒沸石具有较大的比表面积和较高的吸附容量(Qc=158.3 mg/g)。然后测量了乙基十六烷基二甲基溴化铵(EHDa-BR)和十六烷基氯化吡啶(CPC)表面活性剂在清洁和5ppm Cs+污染的斜发沸石上的吸附，在中等浓度的CPC下，分配系数(Kd)高达10,000毫升/克。颗粒大小的测量证实，表面活性剂单分子层的吸附没有导致斜发沸石的显著聚集，而5ppm污染的铯中有8%被重新动员。对于浮选来说，重要的是测量了不同表面活性剂浓度下的回收率和脱水率。结果表明，在最佳工艺条件下，加入0.5μ的磷酸钙骨水泥，加入30μ的MIBC型起泡剂，∼回收率可达90%，减水率可达>；4，突出了浮选分离浓缩泡沫相污染粉尘的可行性。
Flotation using cationic surfactants has been investigated as a rapid separation technique to dewater clinoptilolite ion exchange resins, for the decontamination of radioactive cesium ions (Cs+) from nuclear waste effluent. Initial kinetic and equilibrium adsorption studies of cesium, suggested the large surface area to volume ratio of the fine zeolite contributed to fast adsorption kinetics and high capacities (qc= 158.3 mg/g). Adsorption of ethylhexadecyldimethylammonium bromide (EHDa-Br) and cetylpyridinium chloride (CPC) surfactant collectors onto both clean and 5 ppm Cs+contaminated clinoptilolite was then measured, where distribution coefficients (Kd) as high as 10,000 mL/g were evident with moderate concentrations CPC. Measurements of particle sizes confirmed that adsorption of surfactant monolayers did not lead to significant aggregation of the clinoptilolite, while < 8% of the 5 ppm contaminated cesium was remobilised. Importantly for flotation, both the recovery efficiency and dewatering ratios were measured across various surfactant concentrations. Optimum conditions were found with 0.5 mM of CPC and addition of 30 μL of MIBC frother, giving a recovery of ∼90% and a water reduction ratio > 4, highlighting the great viability of flotation to separate and concentrate the contaminated powder in the froth phase.