邹京,王明铭,豆俊峰,杜明阳,仉铭坤.磷钼酸铵-聚乙烯醇复合材料的制备及其对水中Cs+的吸附性能研究[J].环境科学学报,2021,41(8):3219-3234
磷钼酸铵-聚乙烯醇复合材料的制备及其对水中Cs+的吸附性能研究
- Preparation of ammonium molybdophosphate-polyvinyl alcohol composite and its use of cesium adsorption in aqueous solution
- 基金项目：国家自然科学基金（No.51878051）
- 邹京
- 北京师范大学水科学研究院, 城市水循环与海绵城市技术北京市重点实验室, 北京 100875
- 王明铭
- 1. 北京师范大学水科学研究院, 城市水循环与海绵城市技术北京市重点实验室, 北京 100875;2. 中国电建集团华东勘测设计研究院有限公司, 杭州 310000
- 豆俊峰
- 北京师范大学水科学研究院, 城市水循环与海绵城市技术北京市重点实验室, 北京 100875
- 杜明阳
- 北京师范大学水科学研究院, 城市水循环与海绵城市技术北京市重点实验室, 北京 100875
- 仉铭坤
- 北京师范大学水科学研究院, 城市水循环与海绵城市技术北京市重点实验室, 北京 100875
- 摘要：利用磷钼酸铵、聚乙烯醇和正硅酸四乙酯合成一种新型复合材料（AMP-PVA），运用扫描电镜（SEM）、傅里叶红外光谱（FTIR）、X射线衍射（XRD）、X射线光电子能谱（XPS）和热重分析仪（TG-DSC）等对AMP-PVA进行结构和形貌表征.同时，探究了不同初始浓度、pH、时间等因素对AMP-PVA特异性吸附Cs+性能的影响，并结合等温吸附曲线、吸附动力学等对AMP-PVA的吸附机制进行探讨.结果表明，AMP-PVA可在pH=2~11范围内使用，耐酸性能良好，且在35 ℃、pH=7.7、初始Cs+浓度为200 mg·L-1的条件下达到最大吸附量109.56 mg·g-1；吸附过程以自发的、吸热的、可持续的化学吸附为主，符合Freundlich等温吸附模型和准二级动力学模型，并伴随着内扩散和Boyd模型的特征；AMP-PVA主要作用机制为Cs+与AMP中的NH4+发生离子交换.
- Abstract：A new type of composite material (AMP-PVA) was synthesized by ammonium molybdophosphate, polyvinyl alcohol and tetraethyl orthosilicate. The structure and morphology of AMP-PVA were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and thermogravimetry analysis -differential scanning calorimetry (TG-DSC), respectively. The impact of initial cesium concentration, pH, contact time and other factors on AMP-PVA specific adsorption performance was investigated, and the AMP-PVA adsorption mechanism was explored by isothermal adsorption curve and adsorption kinetics. The results indicated that AMP-PVA can be used in a pH range of 2~11 with appreciable acid and alkali resistance. The maximum adsorption capacity of Cs+ was 109.56 mg·g-1 under the conditions of 35 ℃, pH=7.7 with the initial Cs+ concentration at 200 mg·L-1. The adsorption process is dominated by spontaneous, endothermic and sustainable chemisorption. The Freundlich isotherm model and pseudo-second-order kinetic model fit well for Cs+ adsorption, in which the characteristics of the Weber-Morris interparticle diffusion model and Boyd model were also observed. The ion exchange between Cs+ and NH4+ in AMP is determined to be the main Cs+ adsorption mechanism.
