Preface

The goal of this book, "Strontium Aluminate Cement: Fundamentals, Manufacturing, Hydration, Set‐ ting behaviour and Applications", is to provide the reader with basic overview of this non-traditional binder and to support the researcher`s interest in this topic. Despite the fact, that massive production of strontium aluminate or tri-strontium aluminate cements for industrial application is improbable, the binder shows a few favorable properties. Some of them are described in this book, other must be discov‐ ered first.

Really promising options are the control of reactivity and rate of heat release during the hydration of strontium aluminate cement, the control of processing of strontium aluminate based MDF, of prepara‐ tion of ceramic foam stabilized by strontium aluminate cement and of dense or thermal insulating re‐ fractory castables with tailored thermal expansion for high temperature applications. Moreover, an immense number of combinations can be made for the preparation of blended and multicomponent cements, influence of substitutions on the properties of strontium aluminate. On behalf of all authors I hope that that this publication hold your interest.

> **Petr Ptáček** University of Technology, Czech Republic

#### **Special Thanks**

The authors of this book are honored to spotlight the following co-workers for their immeasurable con‐ tributions in laboratory preparations and specimen analyses: Eva Bartoníčková (Raman spectroscopy), Jiří Másilko (X-ray diffraction analysis), Radoslav Novotný (calorimetry), Jaromír Wasserbauer (electron microscopy), Jiří Švec (thermal analysis and infrared spectroscopy) and Martin Boháč (rheology) and Lukáš Kalina (X-ray photoelectron spectroscopy). I would like to express my appreciation to Halina Szklorzová for language corrections.

#### **Acknowledgements**

This work was supported by the project "Popularization of Brno University of Technology (BUT) R&D results and the support of systematic collaboration with Czech students" No. CZ.1.07/2.3.00/35.0004.

**Chapter 1**

**Introduction**

**knowledge**

periods of time.

**1. Discovery of strontium aluminate cements and current state of**

CaO-Al2O3-H2O has many difficulties, including [1]:

hydration of which is often a problem.

hexagonal (or pseudohexagonal) plates.

are collectively called hydrogrossular [7].

The equation may be written as [4,6]:

**•** The necessity for strict exclusion of carbon dioxide from air.

**•** Relatively low solubility of these compounds.

The experimental study of the system CaO-Al2O3-H2O have considerable practical value not only for its direct contribution to the setting of high-alumina cements (which are composed of mainly anhydrous calcium aluminates) and Portland cements, but also for possible applica‐ tions in the fields of geology, soil equilibrium, water purification, and the extraction of purified hydrated alumina from crude bauxite [1-3,12]. Unfortunately, so far the study of the system

**•** The existence of numerous highly hydrated compounds, the determination of the degree of

**•** The fact that most of the compounds are metastable, yet, once formed; persist over long

**•** Close similarity in crystal habit and optical properties of compounds occurring as thin

According to the results from numerous investigations of chemical reactions related to the hardening of hydraulic cements [4,12], lime and alumina in solution may combine to form isometric tri-calcium aluminate hexahydrate (3CaO∙Al2O3∙6H2O, C3AH6). This compound is isomorphic to C3FH6 garnet as well as grossularite garnet (3CaO∙Al2O3∙3SiO2, C3AS3) and andradite garnet (3CaO∙Fe2O3∙3SiO2). Complete solid solutions exist between each of these compounds and the three others. The hydrous members of the series may be termed hydrogarnets [4,5,198]. The general formula may be written as 3CaO∙Al2O3∙*m*SiO2∙(6-2*m*)H2O, where *m* may vary from 0 to 3 [6]. Hydrogarnets crystal‐ lize in various cubic forms, of which icositetrahedra are probably the most usual at ordinary temperatures. In recent mineralogical nomenclature, the phases in the C3AH<sup>6</sup> – C3AS<sup>3</sup> series

Tri-calcium aluminate hexahydrate decomposes under hydrothermal conditions at about equilibrium temperature 220 – 226°C, yielding calcium hydroxide and less basic aluminate.

> © 2014 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
