黄原胶改良膨润土对Sr2+和Cs+的吸附特性探究
Study on the Adsorption Characteristics of Sr2? and Cs? by Xanthan Gum-Modified Bentonite
纪静茹 1梁维云 2颜荣涛 1冀佳莹1
作者信息
- 1. 桂林理工大学 土木工程学院，广西 桂林 541004
- 2. 信阳师范大学 建筑与土木工程学院，河南 信阳 464000
- 折叠
摘要
安全、高效地处置放射性废弃物是当前环境领域亟待解决的重要问题之一。开发经济、绿色、环保的吸附材料处理核废水，已成为保障环境安全与可持续发展的关键技术问题。本研究选用天然生物聚合物黄原胶（XG）对高庙子膨润土（GMZ）进行改良，制备黄原胶改良高庙子膨润土（XG/GMZ），系统探讨其对核废水中典型放射性核素Sr²⁺和Cs⁺的吸附性能及机制。研究了初始浓度、吸附时间和溶液pH值等因素对XG/GMZ吸附性能的影响，并结合X射线衍射（XRD）、傅里叶变换红外光谱（FTIR）和扫描电子显微镜（SEM）等表征手段，揭示改性机制与微观结构变化。结果表明，随着核素溶液初始浓度的升高，XG/GMZ对Sr²⁺和Cs⁺的总吸附量及离子交换吸附量均呈上升趋势，并在高浓度条件下趋于稳定。吸附机理分析表明，离子交换为主要的吸附机制，尤其在低浓度条件下占比更高。当核素浓度超过8 mmol/L时，XG/GMZ膨润土的吸附能力显著增强。进一步研究发现，XG/GMZ膨润土对Sr²⁺的最优添加量为1.5%，对Cs⁺的最优添加量为0.25%。在Sr²⁺吸附过程中，XG/GMZ表现出更高的吸附量和更快的吸附率；而在Cs⁺吸附过程中，尽管吸附速度没有加快，但吸附效果明显提升。此外，XG/GMZ膨润土在较宽的pH范围内均展现出良好的耐酸碱性能，在复杂水化学环境应用中具有更广泛的适应性。
Abstract
The safe and efficient disposal of radioactive waste remains one of the critical challenges in the field of environmental science. The development of cost-effective, green, and environmentally friendly adsorbent materials for the treatment of nuclear wastewater has emerged as a key technological issue to ensure environmental safety and promote sustainable development. In this study, the natural biopolymer xanthan gum (XG) was employed to modify Gaomiaozi bentonite (GMZ), resulting in the preparation of xanthan gum-modified Gaomiaozi bentonite (XG/GMZ). The adsorption behavior and underlying mechanisms of XG/GMZ toward representative radionuclides, Sr and Cs, in nuclear wastewater were systematically investigated. The effects of initial radionuclide concentration, adsorption time, and solution pH on the adsorption performance of XG/GMZ were investigated. To elucidate the modification mechanism and microstructural changes, a combination of characterization techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM), was employed. The results indicate that both the total adsorption capacity and ion-exchange capacity of XG/GMZ for Sr and Cs increase with rising initial concentrations of the radionuclide solutions, eventually approaching equilibrium at higher concentrations. Mechanistic analysis revealed that ion exchange is the dominant adsorption mechanism, particularly under low-concentration conditions, where its contribution is more pronounced. When the radionuclide concentration exceeded 8 mmol/L, the adsorption capacity of XG/GMZ bentonite was significantly enhanced. Further investigation revealed that the optimal dosage of XG/GMZ for Sr adsorption was 1.5%, while that for Cs was 0.25%. During the adsorption of Sr, XG/GMZ exhibited a higher adsorption capacity and faster adsorption kinetics. In contrast, although the adsorption rate for Cs did not improve significantly, the overall adsorption performance was markedly enhanced. Moreover, XG/GMZ bentonite demonstrated excellent acidbase resistance over a broad pH range, indicating its strong adaptability for application in complex hydrochemical environments.关键词
黄原胶/膨润土/Sr2+/Cs+/吸附Key words
xanthan gum/bentonite/Sr2+/Cs+/adsorption引用本文复制引用
纪静茹,梁维云,颜荣涛,冀佳莹.黄原胶改良膨润土对Sr2+和Cs+的吸附特性探究[EB/OL].(2025-07-21)[2026-04-04].https://chinaxiv.org/abs/202507.00405.学科分类
原子能技术基础理论/放射性废物、放射性废物管理
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