{"title":"Development of a natural inorganic diatomite curing agent on heavy metal-contaminated loess","authors":"Bing Bai, Bixia Zhang, Jing Chen, Hanxiang Feng","doi":"10.1016/j.pce.2024.103790","DOIUrl":null,"url":null,"abstract":"<div><div>Guided by the solidification of loess contaminated with heavy metal ions (HMs), a natural inorganic diatomite (NID) was developed as curing agent under an alkaline activator (AA). The curing time, NID content and AA type on the mechanical properties of contaminated soil and solidification effect of HMs were investigated. The solidification source was analysed by microstructure measurement. As curing time increased, the solidification effect increased, with an optimum curing time of 28 days. The higher the content of NID, the stronger the solidification ability. Nevertheless, the strength showed a tendency of initial increase and subsequent decrease. The strength was maximum when NID content reached 10%. The AA created an alkaline environment to promote solidification. In comparison to Na<sub>2</sub>SiO<sub>3</sub> solution, NaOH solution is more effective in the adsorption of HMs. The larger ionic radius of Pb<sup>2+</sup> relative to Cu<sup>2+</sup>, limited HMs migration ability, thereby facilitating solidification.</div></div>","PeriodicalId":54616,"journal":{"name":"Physics and Chemistry of the Earth","volume":"136 ","pages":"Article 103790"},"PeriodicalIF":3.0000,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physics and Chemistry of the Earth","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1474706524002481","RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Guided by the solidification of loess contaminated with heavy metal ions (HMs), a natural inorganic diatomite (NID) was developed as curing agent under an alkaline activator (AA). The curing time, NID content and AA type on the mechanical properties of contaminated soil and solidification effect of HMs were investigated. The solidification source was analysed by microstructure measurement. As curing time increased, the solidification effect increased, with an optimum curing time of 28 days. The higher the content of NID, the stronger the solidification ability. Nevertheless, the strength showed a tendency of initial increase and subsequent decrease. The strength was maximum when NID content reached 10%. The AA created an alkaline environment to promote solidification. In comparison to Na2SiO3 solution, NaOH solution is more effective in the adsorption of HMs. The larger ionic radius of Pb2+ relative to Cu2+, limited HMs migration ability, thereby facilitating solidification.
以重金属离子(HMs)污染黄土的固化为导向,开发了一种天然无机硅藻土(NID)作为碱性活化剂(AA)下的固化剂。研究了固化时间、NID 含量和 AA 类型对污染土壤力学性能的影响以及 HMs 的固化效果。通过微观结构测量分析了固化源。随着固化时间的增加,固化效应也随之增加,最佳固化时间为 28 天。NID 含量越高,凝固能力越强。然而,强度却呈现出先上升后下降的趋势。当 NID 含量达到 10%时,强度最大。AA 创造了一个促进凝固的碱性环境。与 Na2SiO3 溶液相比,NaOH 溶液对 HMs 的吸附更为有效。相对于 Cu2+,Pb2+ 的离子半径更大,这限制了 HMs 的迁移能力,从而促进了凝固。
期刊介绍:
Physics and Chemistry of the Earth is an international interdisciplinary journal for the rapid publication of collections of refereed communications in separate thematic issues, either stemming from scientific meetings, or, especially compiled for the occasion. There is no restriction on the length of articles published in the journal. Physics and Chemistry of the Earth incorporates the separate Parts A, B and C which existed until the end of 2001.
Please note: the Editors are unable to consider submissions that are not invited or linked to a thematic issue. Please do not submit unsolicited papers.
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(geology, geochemistry, tectonophysics, seismology, volcanology, palaeomagnetism and rock magnetism, electromagnetism and potential fields, marine and environmental geosciences as well as geodesy).
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(hydrology and water resources research, engineering and management, oceanography and oceanic chemistry, shelf, sea, lake and river sciences, meteorology and atmospheric sciences incl. chemistry as well as climatology and glaciology).
-Solar-Terrestrial and Planetary Science:
(solar, heliospheric and solar-planetary sciences, geology, geophysics and atmospheric sciences of planets, satellites and small bodies as well as cosmochemistry and exobiology).