Insights on the role of alumina content and the filler effect on the sulfate requirement of PC and blended cements

Understanding the mechanism controlling the sulfate requirement of blended cements is crucial for a successful deployment of these technologies towards a more sustainable industry. Particularly, clarification regarding the role of alumina content on the sulfate requirement is essential to establish suitable procedures to achieve proper sulfation in practice. In this study, the role of alumina content on the sulfate requirement of cementitious systems is investigated in PC, blends of PC and slag and LC3-type systems. It is observed that adsorption of sulfate on surfaces, mainly C-(A)-S-H, is the overwhelming factor controlling the sulfate demand of these systems. Disso-lution of alumina from slag and metakaolin and adsorption of sulfate in other surfaces seem to have only a minor effect on the overall sulfate requirement. Furthermore, these effects are not correlated with the total amount of alumina present in the SCM used.

About this result

This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.

Karen Scrivener, Franco Alberto Zunino Sommariva
2022
Journal paper

Abstract

Official source

https://infoscience.epfl.ch/record/298108?ln=en

About this result

Related concepts (32)

Related publications (33)

Related MOOCs (3)

Cement Chemistry and Sustainable Cementitious Materials

Learn the basics of cement chemistry and laboratory best practices for assessment of its key properties.

Sorption and transport in cementitious materials

Learn how to study and improve the durability of cementitious materials.

Water quality and the biogeochemical engine

Learn about how the quality of water is a direct result of complex bio-geo-chemical interactions, and about how to use these processes to mitigate water quality issues.

Bayer process

The Bayer process is the principal industrial means of refining bauxite to produce alumina (aluminium oxide) and was developed by Carl Josef Bayer. Bauxite, the most important ore of aluminium, contains only 30–60% aluminium oxide (Al2O3), the rest being a mixture of silica, various iron oxides, and titanium dioxide. The aluminium oxide must be further purified before it can be refined into aluminium metal. The Bayer process is also the main source of gallium as a byproduct despite low extraction yields.

Aluminium oxide

Aluminium oxide (or Aluminium(III) oxide) is a chemical compound of aluminium and oxygen with the chemical formula . It is the most commonly occurring of several aluminium oxides, and specifically identified as aluminium oxide. It is commonly called alumina and may also be called aloxide, aloxite, or alundum in various forms and applications. It occurs naturally in its crystalline polymorphic phase α-Al2O3 as the mineral corundum, varieties of which form the precious gemstones ruby and sapphire.

Aluminium hydroxide

Aluminium hydroxide, , is found in nature as the mineral gibbsite (also known as hydrargillite) and its three much rarer polymorphs: bayerite, doyleite, and nordstrandite. Aluminium hydroxide is amphoteric, i.e., it has both basic and acidic properties. Closely related are aluminium oxide hydroxide, AlO(OH), and aluminium oxide or alumina (), the latter of which is also amphoteric. These compounds together are the major components of the aluminium ore bauxite. Aluminium hydroxide also forms a gelatinous precipitate in water.

Contradict mechanism of long-term magnesium and sodium sulfate attacks of nano silica-modified cement mortars - Experimental and thermodynamic modeling

Qiao Wang

The mechanisms of external sulfate attack on cement mortars containing nano silica have been studied under full immersion conditions after 3 years. The sulfate degradation processes were compared between sodium sulfate and magnesium sulfate solutions with ...

London2024

Atomic-Level and Surface Structure of Calcium Silicate Hydrate Nanofoils

Karen Scrivener, Paul Bowen, Aslam Kunhi Mohamed, Ziga Casar

Deciphering the calcium silicate hydrate (C-S-H) surface is crucial for unraveling the mechanisms of cement hydration and property development. Experimental observations of C-S-H in cement systems suggest a surface termination which is fundamentally differ ...

AMER CHEMICAL SOC2023

The use of supplementary cementitious materials (SCMs) is widely considered the most promis-ing approach to reduce CO2 emissions relative to cement production. SCMs are not commonly present in binders used for special applications. On the other hand, due t ...

EPFL2022