An experimental study on the montmorillonite illitization process in Na-Gaomiaozi bentonite for Chinese EBS

IF 4.2 2区工程技术 Q3 ENGINEERING, ENVIRONMENTAL

Bulletin of Engineering Geology and the Environment Pub Date : 2025-09-05 DOI:10.1007/s10064-025-04462-1

Cong Liu, Yong-Gui Chen, Zhao Sun

{"title":"An experimental study on the montmorillonite illitization process in Na-Gaomiaozi bentonite for Chinese EBS","authors":"Cong Liu, Yong-Gui Chen, Zhao Sun","doi":"10.1007/s10064-025-04462-1","DOIUrl":null,"url":null,"abstract":"<div>Na-Gaomiaozi (GMZ) bentonite has been selected as the buffer material in the Chinese engineering barrier structure (EBS) for nuclear waste disposal. In order to investigated the illitization process of montmorillonite in Na-GMZ bentonite, hydrothermal tests were conducted considering different concentrations of K+, reaction temperatures and times. The mineralogical and colloidal properties of the reacted soil were characterized by X-ray diffraction and zeta potential tests, respectively. The ion concentration of supernatant solution was determined by inductively coupled plasma-optimal emission spectrometer (ICP-OES). The results showed that the presence of K+ promotes the illitization of montmorillonite, and the proportion of illite layers increase with the increasing of K+. Both elevated temperature and time accelerate the illitization of montmorillonite. During the illitization, Si was released from the tetrahedral sheets of montmorillonite. An assessment model of swelling pressure during the illitization of compacted Na-GMZ bentonite is proposed, and the calculated results showing good agreement with experimental data under different K+ concentrations from the literature. This work provides a valuable approach for the phase transformation evaluation of the buffer material in Chinese EBS.</div>","PeriodicalId":500,"journal":{"name":"Bulletin of Engineering Geology and the Environment","volume":"84 10","pages":""},"PeriodicalIF":4.2000,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Bulletin of Engineering Geology and the Environment","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s10064-025-04462-1","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENGINEERING, ENVIRONMENTAL","Score":null,"Total":0}

引用次数: 0

Abstract

Na-Gaomiaozi (GMZ) bentonite has been selected as the buffer material in the Chinese engineering barrier structure (EBS) for nuclear waste disposal. In order to investigated the illitization process of montmorillonite in Na-GMZ bentonite, hydrothermal tests were conducted considering different concentrations of K⁺, reaction temperatures and times. The mineralogical and colloidal properties of the reacted soil were characterized by X-ray diffraction and zeta potential tests, respectively. The ion concentration of supernatant solution was determined by inductively coupled plasma-optimal emission spectrometer (ICP-OES). The results showed that the presence of K⁺ promotes the illitization of montmorillonite, and the proportion of illite layers increase with the increasing of K⁺. Both elevated temperature and time accelerate the illitization of montmorillonite. During the illitization, Si was released from the tetrahedral sheets of montmorillonite. An assessment model of swelling pressure during the illitization of compacted Na-GMZ bentonite is proposed, and the calculated results showing good agreement with experimental data under different K⁺ concentrations from the literature. This work provides a valuable approach for the phase transformation evaluation of the buffer material in Chinese EBS.

Abstract Image

查看原文本刊更多论文

中国EBS用纳高庙子膨润土中蒙脱土溶出过程的实验研究

我国核废料处理工程屏障结构（EBS）选用纳高庙子（GMZ）膨润土作为缓冲材料。为了研究蒙脱土在Na-GMZ膨润土中的钝化过程，在不同K+浓度、反应温度和反应时间下进行了水热试验。用x射线衍射和zeta电位测试分别表征了反应土的矿物学和胶体性质。采用电感耦合等离子体最佳发射光谱仪（ICP-OES）测定上清溶液的离子浓度。结果表明：K+的存在促进了蒙脱石的伊利石化，伊利石层的比例随着K+的增加而增加；升高的温度和时间都加速了蒙脱石的非石化化。在钝化过程中，硅从四面体蒙脱土中释放出来。建立了Na-GMZ膨润土在不同K+浓度下活化过程中膨胀压力的评价模型，计算结果与文献中实验数据吻合较好。本研究为我国EBS缓冲材料的相变评价提供了一种有价值的方法。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Bulletin of Engineering Geology and the Environment 工程技术-地球科学综合

CiteScore

7.10

自引率

11.90%

发文量

445

审稿时长

4.1 months

期刊介绍： Engineering geology is defined in the statutes of the IAEG as the science devoted to the investigation, study and solution of engineering and environmental problems which may arise as the result of the interaction between geology and the works or activities of man, as well as of the prediction of and development of measures for the prevention or remediation of geological hazards. Engineering geology embraces: • the applications/implications of the geomorphology, structural geology, and hydrogeological conditions of geological formations; • the characterisation of the mineralogical, physico-geomechanical, chemical and hydraulic properties of all earth materials involved in construction, resource recovery and environmental change; • the assessment of the mechanical and hydrological behaviour of soil and rock masses; • the prediction of changes to the above properties with time; • the determination of the parameters to be considered in the stability analysis of engineering works and earth masses.