摘要
通过沉降实验研究了不同浓度高岭土和蒙脱土分别对富勒烯纳米颗粒(nC_(60))稳定性的影响,利用沉降模型并结合zeta电位、粒径、SEM、TEM进行原因分析.单体系中nC_(60)的稳定性好,高岭土胶体稳定性差且随浓度增加而降低,蒙脱土胶体稳定性好且与浓度无明显关系.整体上,高岭土和蒙脱土可以降低nC_(60)的稳定性.随着高岭土浓度增加,nC_(60)稳定性显著降低;而蒙脱土对nC_(60)稳定性降低较小且与浓度无明显关系.结果表明,nC_(60)的稳定性由黏土控制,两种黏土在结构和比表面积上的差异,使它们对nC_(60)稳定性影响不同.模型分析表明,一阶沉降模型和修正的一阶沉降模型分别适用于高岭土和蒙脱土参与的胶体沉降过程.该研究可为评估nC_(60)对地下水环境的影响提供重要参考.
The sedimentation tests for nC_(60)in the presence of kaolinite and montmorillonite with different mass concentration ratios were conducted and fitted with two sedimentation models.Meanwhile,the particle zeta potential and size analysis as well as SEM and TEM tests were implemented to examine the stability of the particles.It has been observed that nC_(60)was stable in the single system.The stability of kaolinite particles significantly decreased with increasing concentration in the single system,however,the montmorillonite particles was overall stable and it was independent of its concentration.In the binary system,the stability of nC_(60)decreased significantly with the increase of kaolinite concentration.The stability of nC_(60),however,was basically not affected by montmorillonite and had no relation to the montmorillonite concentration.The result of this study showed that the clay minerals played a role in the stability of nC_(60)and the difference in the structure and specific surface area of kaolinite and montmorillonite was probably the reason for their different effects on nC_(60)stability.The two different sedimentation models showed that semi-empirical model was better to simulate the sedimentation process related to montmorillonite particles,while the theoretical sedimentation model showed better fitting results associated with kaolinite colloids and kaolinite/nC_(60)mixtures.This study can serve as a reference to assess the contamination of nC_(60)on groundwater.
作者
湛伟勇
刘观胜
钟华
ZHAN Wei-yong;LIU Guan-sheng;ZHONG Hua(School of Water Resources and Hydropower Engineering,Wuhan University,Hubei 430072,China)
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2021年第3期1366-1377,共12页
China Environmental Science
基金
国家自然科学基金资助项目(51979203)
国家水体污染控制与治理重大科技专项项目(2017ZX07108-001)。
