Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
3.9
2.5
Journals
Minerals
Special Issues
Cement Related Minerals—in Memory of Herbert Pöllmann
share announcement

Cement Related Minerals—in Memory of Herbert Pöllmann

A special issue of Minerals (ISSN 2075-163X). This special issue belongs to the section "Crystallography and Physical Chemistry of Minerals & Nanominerals".

Deadline for manuscript submissions: closed (24 May 2023) | Viewed by 14953

Special Issue Editors

Dr. Krassimir Garbev

E-Mail Website
Guest Editor
Karlsruhe Institute of Technology, Institute for Technical Chemistry (ITC), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
Interests: CSH phases; XRD; Raman and IR spectroscopy; synthesis; phase transformations
Dr. Jiaqi Li

E-Mail Website
Guest Editor
Department of Civil and Environmental Engineering, University of California, Berkeley115 Davis Hall, Berkeley, CA 94720, USA
Interests: calcium silicate hydrate; tobermorite; magnesium phosphate cement; high-pressure techniques

Special Issue Information

Dear Colleagues,

Cement production is one of the most CO2- and energy-intensive industries. A great endeavor has been in progress to reduce its carbon footprint. Of particular interest are nonstandard solutions, including developing cementation materials out of calcium silicates (hydrates) with low Ca/Si ratios. In addition, the recycling of construction materials could rely on CSH minerals as intermediate products. In addition to the CSH phases, other hydrates such as AFm or AFT phases (Ettringite) can also play an important role in new cement types for CO2 reduction or immobilization technologies. The extraordinary variations of silicate structures observed in the large family of cement relevant minerals provide a solid basis for engineering and tailoring the properties of novel cementitious materials.

In the several decades since the first comprehensive work of H.F.W. Taylor, extensive studies have been published, not only filling gaps of missing data but also providing structures of newly discovered minerals. One of the greatest achievements, the deciphering of the structure of the nanocrystalline calcium silicate hydrates, the backbone of the hardened cement paste, was only made possible after solving the complex structures of various tobermorite minerals. Other hydration products also produce a new variety of interesting mineral structures. The range of analytical data used for characterization grows correspondingly, including increasing uses of synchrotron-based techniques. Nonetheless, a huge amount of work still needs to be done in this field, marked by a high grade of application relevance. 

The Special Issue on “Cement-Related Minerals” aims to emphasize the importance of such compounds as possible resources for materials development with a reduced carbon footprint and to expand the knowledge of their fundamental properties. 

Papers with a special focus on the synthesis, formation kinetics, structure, relations, modularity, and isomorphic substitutions of cement-relevant mineral phases are encouraged. Key aspects may include investigations of their behavior and resulting phase transformations at elevated pressure or temperature. Theoretical and experimental works of the fundamental properties of cement minerals are also welcome to this issue. Phases in alternative cement/binder systems, including but not limited to calcium (sulfo)aluminate, magnesium phosphate, and alkali-activated materials, are also welcome. This call includes the application of new approaches and analytical spectroscopic techniques based on the use of both conventional and synchrotron radiation. 

We hope that this Special Issue will encourage mineralogists, chemists, and material scientists to share their research on this topic with a significant impact on our society.

This Special Issue is dedicated to Prof. Dr. Herbert Pöllmann on the occasion of his unexpected passing.

Dr. Krassimir Garbev
Dr. Jiaqi Li
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Minerals is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • clinker minerals
  • calcium silicate hydrates
  • AFm Aft minerals
  • Structure
  • phase transformations
  • material properties
  • alternative cement materials

Published Papers (7 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

17 pages, 5756 KiB  
Article
Chlorellestadite (Synth): Formation, Structure, and Carbonate Substitution during Synthesis of Belite Clinker from Wastes in the Presence of CaCl2 and CO2
by Krassimir Garbev, Angela Ullrich, Günter Beuchle, Britta Bergfeldt and Peter Stemmermann
Minerals 2022, 12(9), 1179; https://doi.org/10.3390/min12091179 - 19 Sep 2022
Cited by 3 | Viewed by 1607
Abstract
The synthesis of low-temperature belite (C2S) clinker from wastes of autoclaved aerated concrete and limestone was studied in the presence of CaCl2 as a mineralizing agent. Synthetic chlorellestadite (SCE; Ca10(SiO4)3(SO4)3Cl [...] Read more.
The synthesis of low-temperature belite (C2S) clinker from wastes of autoclaved aerated concrete and limestone was studied in the presence of CaCl2 as a mineralizing agent. Synthetic chlorellestadite (SCE; Ca10(SiO4)3(SO4)3Cl2) forms in experiments at temperatures between 700 and 1200 °C. Samples were investigated by X-ray diffraction and Raman spectroscopy. In general, the amount of SCE depends mainly on the sulfate content and to a lesser extent on the synthesis temperature. At lower temperatures of formation, a non-stoichiometric SCE seems to crystallize in a monoclinic symmetry similar to hydroxylellestadite. Rietveld refinements revealed the presence of chlorine and calcium vacancies. Raman spectroscopy proved the partial substitution of sulfate by CO32− groups in ellestadites formed at 800 °C and 900 °C in air. Incorporation of CO3 results in a shorter unit cell parameters and smaller cell volume similar to CO3−apatite. At low temperatures, SCE coexists with spurrite intermixed on a very fine nm scale. At temperatures above 900 °C in air, ellestadite is carbonate-free and above 1000 °C chlorine loss starts in all samples. Full article
(This article belongs to the Special Issue Cement Related Minerals—in Memory of Herbert Pöllmann)
►▼ Show Figures

Graphical abstract

19 pages, 3227 KiB  
Article
CaCl2 as a Mineralizing Agent in Low-Temperature Recycling of Autoclaved Aerated Concrete: Cl-Immobilization by Formation of Chlorellestadite
by Angela Ullrich, Krassimir Garbev, Uwe Schweike, Michael Köhler, Britta Bergfeldt and Peter Stemmermann
Minerals 2022, 12(9), 1142; https://doi.org/10.3390/min12091142 - 09 Sep 2022
Cited by 4 | Viewed by 1451
Abstract
The suitability of CaCl2 as a mineralizing agent in the synthesis of a low-temperature C2S-cement clinker from wastes of autoclaved aerated concrete was investigated. As chlorellestadite is a potential host mineral for the immobilization of chlorine, the formation conditions for [...] Read more.
The suitability of CaCl2 as a mineralizing agent in the synthesis of a low-temperature C2S-cement clinker from wastes of autoclaved aerated concrete was investigated. As chlorellestadite is a potential host mineral for the immobilization of chlorine, the formation conditions for the highest joint content of chlorellestadite and C2S were studied in samples with different sulfate contents. Oven experiments were conducted at temperatures between 700 and 1200 °C. The samples were analyzed by X-ray diffraction in combination with chemical and thermal analysis and Raman spectroscopy. Calculation of the yield of C2S and ellestadite for all samples proves the optimum temperature range for the C2S-ellestadite clinker from 950 to 1000 °C. At lower temperatures, the formation of a carbonate-rich halogenide melt promotes the crystallization of a significant amount of spurrite at the expense of C2S. Ellestadite formation mainly depends on the sulfate content and to a lesser extent on the synthesis temperature. However, at higher temperatures, with ternesite another sulfate coexists in sulfate-rich samples at the expense of ellestadite. In addition, distinct evidence for non-stoichiometry and carbonate substitution in the structure of low-temperature ellestadite was found. Low sulfate content leads to the crystallization of Ca10[Si2O7]3Cl2 at higher temperatures. In all samples treated at temperatures above 1000 °C chlorine loss starts. Its extent decreases with increasing sulfate content. Full article
(This article belongs to the Special Issue Cement Related Minerals—in Memory of Herbert Pöllmann)
►▼ Show Figures

Graphical abstract

15 pages, 3755 KiB  
Article
Characterization of Monochromate and Hemichromate AFm Phases and Chromate-Containing Ettringite by 1H, 27Al, and 53Cr MAS NMR Spectroscopy
by Shuai Nie and Jørgen Skibsted
Minerals 2022, 12(3), 371; https://doi.org/10.3390/min12030371 - 17 Mar 2022
Cited by 2 | Viewed by 2188
Abstract
The calcium aluminate hydrate AFm and AFt phases formed upon hydration of Portland cement have an important role in the stabilization and solidification of hazardous chromate ions in hardened cement. AFm monochromate (Ca4[Al(OH)6]2(CrO4)·12H2O), [...] Read more.
The calcium aluminate hydrate AFm and AFt phases formed upon hydration of Portland cement have an important role in the stabilization and solidification of hazardous chromate ions in hardened cement. AFm monochromate (Ca4[Al(OH)6]2(CrO4)·12H2O), AFm hemichromate (Ca4[Al(OH)6]2(CrO4)0.5(OH)·12H2O) and the chromate-containing AFt phase, Ca6[Al(OH)6]2-(CrO4)3·24H2O, were synthesized and investigated by 1H, 27Al, and 53Cr MAS NMR spectroscopy. 27Al quadrupolar coupling parameters (CQ, ηQ) and isotropic chemical shifts (δiso) were determined for the three phases, including two distinct Al sites in chromate-AFt, as observed by 27Al MAS and MQMAS NMR. Two dominant peaks are apparent in the 1H MAS NMR spectra of each of the phases. For the AFm phases, these resonances are assigned to framework hydroxyl groups (1.7–2.0 ppm) and water molecules/hydroxyls (5.0–5.5 ppm) in the interlayer. For chromate-AFt, the peaks are ascribed to framework hydroxyl groups in the [Ca6Al2(OH)12]6+ columns (~1.4 ppm) and water molecules (~4.8 ppm) associated with the Ca ions. 53Cr MAS NMR spectra acquired at 22.3 T for the samples show a narrow resonance for both chromate AFm phases, whereas indications of three distinct Cr resonances are apparent for the chromate AFt. The absence of any second-order quadrupolar effects in the 53Cr NMR spectra strongly suggests that the chromate ions are highly mobile in the anionic sites of the AFm and AFt structures. The NMR data reported in this work are in agreement with the reported crystal structures for the chromate AFm and AFt phases and may be useful for identification and characterization of chromate fixation in cementitious systems, complementing information gained from conventional powder X-ray diffraction studies. Full article
(This article belongs to the Special Issue Cement Related Minerals—in Memory of Herbert Pöllmann)
►▼ Show Figures

Figure 1

28 pages, 6250 KiB  
Article
A Porous Stone Technique to Measure the Initial Water Uptake by Supplementary Cementitious Materials
by Andras Fehervari, Will P. Gates, Chathuranga Gallage and Frank Collins
Minerals 2021, 11(11), 1185; https://doi.org/10.3390/min11111185 - 26 Oct 2021
Cited by 4 | Viewed by 1852
Abstract
The decades-long use of supplementary cementitious materials (SCMs) as replacements for ordinary Portland cement (OPC) by the cement and concrete industry is undergoing a resurgence in research activities related to goals addressing circular economy activities, as well as reduction in CO2 emissions. [...] Read more.
The decades-long use of supplementary cementitious materials (SCMs) as replacements for ordinary Portland cement (OPC) by the cement and concrete industry is undergoing a resurgence in research activities related to goals addressing circular economy activities, as well as reduction in CO2 emissions. Differences in the chemistry, mineralogy and reactivity of SCMs compared to OPC impact the fresh properties of concrete. Some SCMs exhibit greater initial water uptake and thus compete strongly with OPC for water during hydration. This study focuses on the early interaction with water as a primary factor that determines the resulting fresh properties and workability. Currently, no test (standard or otherwise) is available for quantifying initial interactions between water and cementitious materials. A quick and reliable method to measure the initial water uptake of SCMs is presented herein, which relies on their affinity to water. The method enables the calculation of water-to-binder ratios for different SCMs required to achieve the same workability as a reference OPC. The results are then well correlated to measured slump and bleed properties. We propose this simple technique to be used by researchers and industry practitioners to better predict the fresh properties of concretes, mortars, or pastes with SCMs. Full article
(This article belongs to the Special Issue Cement Related Minerals—in Memory of Herbert Pöllmann)
►▼ Show Figures

Figure 1

12 pages, 1220 KiB  
Article
Uptake of Be(II) by Cement in Degradation Stage I: Wet-Chemistry and Molecular Dynamics Studies
by Neşe Çevirim-Papaioannou, Sangsoo Han, Iuliia Androniuk, Wooyong Um, Marcus Altmaier and Xavier Gaona
Minerals 2021, 11(10), 1149; https://doi.org/10.3390/min11101149 - 18 Oct 2021
Cited by 5 | Viewed by 1426
Abstract
The uptake of beryllium by hardened cement paste (HCP, with CEM I 42,5 N BV/SR/LA type) in degradation stage I was investigated with a series of batch sorption experiments with 10−6 M ≤ [Be(II)]0 ≤ 10−2.5 M and 2 g·L [...] Read more.
The uptake of beryllium by hardened cement paste (HCP, with CEM I 42,5 N BV/SR/LA type) in degradation stage I was investigated with a series of batch sorption experiments with 10−6 M ≤ [Be(II)]0 ≤ 10−2.5 M and 2 g·L−1 ≤ [S/L] ≤ 50 g·L−1. All experiments were performed under Ar atmosphere at T = (22 ± 2) °C. Solubility limits calculated for α-Be(OH)2(cr) in the conditions of the cement pore water were used to define the experimental window in the sorption experiments. Beryllium sorbs strongly on HCP under all of the investigated conditions, with log Rd ≈ 5.5 (Rd in L⋅kg−1). Sorption isotherms show a linear behavior with a slope of ≈+1 (log [Be(II)]solid vs. log [Be(II)]aq) over four orders of magnitude (10−8 M ≤ [Be(II)]aq ≤ 10−4 M), which confirm that the uptake is controlled by sorption processes and that solubility phenomena do not play any role within the considered boundary conditions. The similar uptake observed for beryllium in calcium silicate hydrate (C-S-H) phases supports that the C-S-H phases are the main sink of Be(II) in cement. The strong uptake observed for Be(II) agrees with the findings reported for heavier metal ions, e.g., Zn(II), Eu(III), Am(III), or Th(IV). The exceptional sorption properties of beryllium can be partially explained by its small size, which result in a charge-to-size ratio (z/d) of the same order as Eu(III) or Am(III). Kinetic experiments confirm the slow uptake of Be(II), which is characterized by a two-step process. In analogy to other strongly sorbing metal ions such as Zn(II) or Th(IV), a fast surface complexation (t < 4 days) followed by a slower incorporation of Be(II) in the C-S-H structure (t ≥ 60 days) are proposed. The surface complexation was studied in detail with molecular dynamic simulations, and the most common surface species are identified and described. This work provides the first experimental evidence supporting the strong uptake of Be(II) by HCP in degradation stage I, further extending previous findings on C-S-H phases and HCP in degradation stage II. These results overcome previous conservative estimates assuming no or only a weak uptake in cementitious systems and represent a relevant contribution for the quantitative assessment on the retention/mobilization of beryllium in the context of nuclear waste disposal. Full article
(This article belongs to the Special Issue Cement Related Minerals—in Memory of Herbert Pöllmann)
►▼ Show Figures

Figure 1

22 pages, 3061 KiB  
Article
In Situ X-ray Diffraction at High Temperatures: Formation of Ca2SiO4 and Ternesite in Recycled Autoclaved Aerated Concrete
by Angela Ullrich, Krassimir Garbev and Britta Bergfeldt
Minerals 2021, 11(8), 789; https://doi.org/10.3390/min11080789 - 21 Jul 2021
Cited by 11 | Viewed by 2699
Abstract
This study provides an insight into possible recycling processes for autoclaved aerated concrete (AAC) at low temperatures (<1000 °C). Belite binders were synthesized from wastes of AAC by the addition of CaCO3 and adaption of the molar CaO/SiO2 (C/S ratio) in [...] Read more.
This study provides an insight into possible recycling processes for autoclaved aerated concrete (AAC) at low temperatures (<1000 °C). Belite binders were synthesized from wastes of AAC by the addition of CaCO3 and adaption of the molar CaO/SiO2 (C/S ratio) in the range of 2 to 2.5. An in situ XRD study performed during heating up to 1000 °C and subsequent quenching to room temperature evidenced the formation of ternesite besides C2S in sulfate-containing systems. Several factors influencing the reaction kinetics and the evolution of the phase composition were investigated thoroughly. Increased sulfate content and dwelling time during heating increase the ternesite content and promote the formation of highly crystalline α’H-C2S. The C/S-ratio of the starting materials has to be adjusted to the sulfate content in order to prevent the formation of ternesite at the expense of C2S. Ternesite remains stable during quenching to room temperature or even increases in amount, except in cases of very low cooling rates or high residual quartz contents (C/S-ratio ≤ 2). Temperature and range of α’H-C2S to β-C2S phase transition on quenching strongly depend on the cooling rate. The onset temperature for β-C2S formation varies between 540 °C (slow quench) and 450 °C (fast quench). Thermal expansion coefficients of ternesite are calculated showing similarity with C2S. The incorporation of CaSO4 modules in the structure switches the direction of maximum compression. Full article
(This article belongs to the Special Issue Cement Related Minerals—in Memory of Herbert Pöllmann)
►▼ Show Figures

Figure 1

22 pages, 7045 KiB  
Article
X-ray Total Scattering Study of Phases Formed from Cement Phases Carbonation
by Ana Cuesta, Angeles G. De la Torre and Miguel A. G. Aranda
Minerals 2021, 11(5), 519; https://doi.org/10.3390/min11050519 - 14 May 2021
Cited by 5 | Viewed by 2219
Abstract
Carbonation in cement binders has to be thoroughly understood because it affects phase assemblage, binder microstructure and durability performance of concretes. This is still not the case as the reaction products can be crystalline, nanocrystalline and amorphous. The characterisation of the last two [...] Read more.
Carbonation in cement binders has to be thoroughly understood because it affects phase assemblage, binder microstructure and durability performance of concretes. This is still not the case as the reaction products can be crystalline, nanocrystalline and amorphous. The characterisation of the last two types of components are quite challenging. Here, carbonation reactions have been studied in alite-, belite- and ye’elimite-containing pastes, in controlled conditions (3% CO2 and RH = 65%). Pair distribution function (PDF) jointly with Rietveld and thermal analyses have been applied to prove that ettringite decomposed to yield crystalline aragonite, bassanite and nano-gibbsite without any formation of amorphous calcium carbonate. The particle size of gibbsite under these conditions was found to be larger (~5 nm) than that coming from the direct hydration of ye’elimite with anhydrite (~3 nm). Moreover, the carbonation of mixtures of C-S-H gel and portlandite, from alite and belite hydration, led to the formation of the three crystalline CaCO3 polymorphs (calcite, aragonite and vaterite), amorphous silica gel and amorphous calcium carbonate. In addition to their PDF profiles, the thermal analyses traces are thoroughly analysed and discussed. Full article
(This article belongs to the Special Issue Cement Related Minerals—in Memory of Herbert Pöllmann)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-7
Back to TopTop