Publication detail

Comparison of thermogravimetry response of alkali-activated slag and Portland cement pastes after stopping their hydration using solvent exchange method

BÍLEK, V. ŠVEC, J. MÁSILKO, J. SEDLAČÍK, M. WIECZOREK, A. MATERAK, K. KONIORCZYK, M. HAJZLER, J. KUCHARCZYKOVÁ, B.

Original Title

Comparison of thermogravimetry response of alkali-activated slag and Portland cement pastes after stopping their hydration using solvent exchange method

Type

journal article in Web of Science

Language

English

Original Abstract

The critical step for any subsequent instrumental analysis of cementitious binders is to stop their hydration reactions, i.e., to remove free water. One of the most available techniques is a solvent exchange method. However, the solvents are known to be strongly bound in ordinary Portland cement (OPC) paste and alter the results of thermogravimetric analysis (TGA) and sensitive hydrates, while their effect on TGA response of alkali-activated slag (AAS) has not been comprehensively investigated. Therefore, the objective of this paper is to track the effects of fundamental aspects of the solvent exchange on the TGA response of AAS with different sodium activators (hydroxide, carbonate, waterglass) and to support these results by X-ray diffraction and effluent gas analysis. All solvents used (acetone, diethyl ether, isopropyl alcohol, ethanol, and methanol) affected the TGA response of all tested pastes, and their effect was enhanced by prolonged immersion time. All solvents induced an additional mass loss at around 800 degrees C and, especially for OPC paste, increased in situ carbonation, even in an inert atmosphere. Methanol and ethanol had a detrimental effect on ettringite and decreased the basal distance of the C-(A)-S-H gel, while they only marginally affected gaylussite. For AAS, hydration stoppage by washing out the alkali-rich pore solution with water was also investigated and can usually be recommended (except for its detrimental effect on gaylussite), as it is more efficient than organic solvents, which lack solubility for activators. Methanol and ethanol are the most suitable alternatives, particularly for NaOH.

Keywords

Alkali-activated slag; Cement; Solvent exchange; Organic solvents; Thermogravimetry; Carbonation

Authors

BÍLEK, V.; ŠVEC, J.; MÁSILKO, J.; SEDLAČÍK, M.; WIECZOREK, A.; MATERAK, K.; KONIORCZYK, M.; HAJZLER, J.; KUCHARCZYKOVÁ, B.

Released

18. 8. 2024

Publisher

SPRINGER

Location

DORDRECHT

ISBN

1588-2926

Periodical

Journal of Thermal Analysis and Calorimetry

Number

2424

State

Hungary

Pages count

25

URL

BibTex

@article{BUT189813,
  author="Vlastimil {Bílek} and Jiří {Švec} and Jiří {Másilko} and Martin {Sedlačík} and Alicja {Wieczorek} and Kalina {Materak} and Marcin {Koniorczyk} and Jan {Hajzler} and Barbara {Kucharczyková}",
  title="Comparison of thermogravimetry response of alkali-activated slag and Portland cement pastes after stopping their hydration using solvent exchange method",
  journal="Journal of Thermal Analysis and Calorimetry",
  year="2024",
  number="2424",
  pages="25",
  doi="10.1007/s10973-024-13552-3",
  issn="1588-2926",
  url="https://link.springer.com/article/10.1007/s10973-024-13552-3"
}