Alkali activation of natural clay using a Ca(OH)2/Na2CO3 alkaline mixture

Author:

Shaqour F.,Ismeik M.,Esaifan M.

Abstract

AbstractAn experimental investigation was conducted on the alkali activation of a kaolinitic clay using an alkaline mixture composed of hydrated lime (Ca(OH)2) and sodium carbonate (Na2CO3) solution. The Ca(OH)2/Na2CO3 alkaline mixture was developed to overcome the high cost and chemical aggression associated with classical alkaline solutions. The mineralogical composition and microstructure of the alkaline mixture and alkali-activation products were studied using X-ray diffraction, attenuated total reflectance-Fourier transform infrared spectroscopy, thermogravimetric analysis and energy-dispersive X-ray-scanning electron microscopy techniques. Pirssonite (Na2Ca(CO3)2·2H2O), calcite (CaCO3), and sodium hydroxide (NaOH) formed as a result of mixing of Ca(OH)2 with Na2CO3. The alkali activation of natural clay with the Ca(OH)2/Na2CO3 alkaline mixture produced a binding agent identified as hydroxysodalite phase (Na8Al6Si6O24(OH)2·4H2O) when pure kaolinite was used, and cancrinite carbonate (Na6Ca1.5[Al6Si6O24](CO3)1.5·1.8H2O) when kaolinitic clay with high a calcite content was used. The mechanical strength of the binder developed was evaluated on cylindrical specimens containing granite waste as a filler material under dry and soaked conditions. The classical NaOH activator was used for comparison. For specimens produced using a Ca(OH)2/Na2CO3 mixture as the alkaline activator, the recorded strength valuewas 21 MPa which was 35% less than that achieved by the classical NaOH solution. Durability tests on samples soaked in water for 24 h showed a reduction in strength from 34 to 22 MPa for specimens prepared with NaOH solution, and from 21 to 11 MPa for the specimens prepared with a Ca(OH)2/Na2CO3 alkaline mixture.

Publisher

Mineralogical Society

Subject

Geochemistry and Petrology

Cited by 27 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3