TOBERMORITE AND TOBERMORITE-L/KE CALCIUM SILICATE HYDRATES: \ THEIR PROPERTIES AND RELATIONSHIPS TO CLAY MINERALS AUG. 1963 NO. 24 DIAMOND PURDUE UNIVERSITY LAFAYETTE INDIANA Final Report TOBERMDRITE AND TOBERMORITE-LIKE CALCIUM SILICATE HYDRATES: THEIR PROPERTIES AND RELATIONSHIPS TO CIAY MINERALS TO: K. B. Woods, Director Joint Highway Research Project August 2, 1963 PROM: H. L. Michael, Associate Director File: 4-6-9 Joint High-way Research Project Project: C=36-^7I Attached is a Final Report "by Mr. Sidney Diamond, Graduate Assistant on our staff, entitled "Tobermorite and Tobermorite-Like Calcium Silicate Hydrates: Their Properties and Relationships to Clay Minerals"., This research has been performed under the direction of Professors J. L. White of the Purdue University Agronomy Department and Professor W. L. Dolch of our staff. Mr. Diamond also used the report as his disertation for the Ph.D. Degree. The Plan of Study for this research was approved by the Board on May 22, 1962, and it subsequently was approved by the Indiana State Highway Commission and the Bureau of Public Roads as an HPS research project. This is the final report on this project and it will be submitted to the sponsoring organization for review. Several papers from the research are anticipated and each will be submitted to the Board and the sponsors for review and approval prior to publication. The report is submitted to the Board for information and for the record. Respectfully submitted, Harold L. Michael, Secretary HLM:bc Attachment Copies: F. L. Ashbaucher J. F. McLaughlin J. R. Cooper R. D. Miles W. L. Dolch R. E. Mills W. H. Goetz M. B. Scott F. F. Havey J. V. Smythe F. S. Hill B. J. Yoder G. A. Leonards Final Report TOBEEMORITE MID TOBERMORITE-LIKE CALCIUM SILICATE HYDRATES: THEIR PROPERTIES AND RELATIONSHIPS TO CIAY MINERALS by Sidney Diamond Graduate Assistant Joint Highway Research Project File No: U-6-9 Project No: C-36-47T Purdue University- Lafayette, Indiana August 2, 1963 Digitized by the Internet Archive in 2011 with funding from LYRASIS members and Sloan Foundation; Indiana Department of Transportation http://www.archive.org/details/tobermoritetoberOOdiam ii ACKNOWLEDGMENTS The author is deeply grateful to Dr. Joe L. White, his major professor, and to Dr. W. L. Dolch, co-chairman of his advisory committee, for their assistance, advice, and un- failing encouragement throughout his period of graduate study. Thanks are also due to Dr. Elchard W. Lounsbury and Dr. James W. Richardson, who served as 'members of his advisory committee. Most of the research was conducted in the laboratories of the agronomy Department of Purdue University. The study was supported by a grant to the Joint Highway Research Project of Purdue University by the State Highway Department of Indiana and the U.S. Bureau of Public Roads. Their generous support is much appreciated. The author is further indebted to the Bureau of Public Roads for financial support of a portion of his period of graduate study as an out-service training activity. Samples of pure calcium silicates employed in this work were generously donated by the Portland Cement Association Research and Development Laboratories, and a sample of alite was kindly supplied by Mr. Alexander Klein of the University of California. These gifts are acknowledged with thanks. The electron micrographs presented in this report were taken by Dr. John Rudovlch of Micro-Met Laboratories, Inc. Mr. John Allen and Mrs. Joanne Johannsen assisted in many of ill the laboratory procedures. A number of chemical analyses were performed by Mr. Larry Campbell and Mr. Lawrence Schuppert. The author is most grateful to all of these persons. It is a pleasure to acknowledge the author's indebtedness to a number of his associates at Purdue University, both staff members and graduate students, for stimulating discussions on many occasions and for the use of research equipment. A particularly valuable discussion with Dr. G. L. Kalousek of the Universal Atlas Cement Company is also gratefully acknow- ledged . Most of all, the author wishes to record his gratitude to his wife, Harriet, and to his children, whose encouragement and support were never lacking. iv TABLE OF CONTENTS Page LIST OP TABLES lx LIST OF ILLUSTRATIONS x ABSTRACT xiv INTRODUCTION 1 REVIEW OF THE LITERATURE k Introduction and Notation k Tobermorite 5 Origin, Synthesis, and Optical Properties 5 Composition, Structure, and Morphology 7 Chemical Composition and Extent of Variation 7 Hydration States 8 Crystal Structure 10 Morphology 13 Differential Thermal Analysis 13 Infrared Absorption 14 Surface ^rea 15 Surface Charge 16 Cation Exchange Properties 17 Summary . 18 Calcium Silicate Hydrate (I) 19 Nomenclature and Synthesis 19 Composition, Structure and Morphology 21 Variation in Chemical Composition 21 Hydration States 22 Variation in Basal Spacing Due to Composition .... 22 X-ray Diffraction and Crystal Structure 23 Morphology 25 Differential Thermal Analysis 26 Infrared Absorption 27 Surface Areas and other Characteristic Properties of CSH(I) 28 Summary 28 Calcium Silicate Hydrate (II) 30 Nomenclature and Synthesis 3° Composition, Structure, and Morphology 3° Variation in Chemical Composition 3° X-ray Diffraction and Crystal Structure of CSH(II) 31 Morphology 32 Differential Thermal Analysis 33 Page Infrared Absorption 33 Surface Areas and other Characteristic Properties of CSH(II) 33 Summary 34 Calcium Silicate Hydrate (gel) 35 Nomenclature and Origin 35 Composition, Structure and Morphology 36 Variation in Chemical Composition 36 X-ray Diffraction and Crystal Structure 37 Morphology 39 Differential Thermal Analysis 39 Infrared Absorption 40 Surface Area and other Characteristic Properties of CSH(gel) 41 Surface Area Measurements 4l Surface Charge and Surface Energy of CSH(gel) 4-3 Cation Exchange Properties 44 Thermodynamic Properties 44 Summary 44 Hydrated Calcium Aluminates and Related Compounds .... 45 Introduction to the Types of Compounds that Occur 45 The Cubic Phase C3AH5 4? The Hexagonal Phases C.AH , C AH , CAH , 2 u and Related Phases r. i-> . V . t 48 fyAHjo 48 C2AH8 50 CAH 50 The Supposed Phase C3AH12 51 Compounds of Needle-llKe Habit 51 Summary 51 Clay Minerals Reaction Products of Ca(0H) 2 with 52 MATERIALS AND PROCEDURES 60 Preparation of Calcium Silicate Hydrates 60 Well-Crystallized Tobermorite 60 Unsubstituted Tobermorite 60 Substituted Tobermorites 61 Poorly-Crystallized Calcium Silicate Hydrates Synthesized at Room Temperature 62 Samples Prepared by Double Decomposition Methods . 62 Samples Prepared by Direct Synthesis 64 Attempted Synthesis of CSH(II) by Direct Reaction in Hot Glycerol 65 Hydration Products of Individual Cement Minerals ... 66 Cement Minerals °6 "Paste" Hydration 66 "Bottle 1 " Hydration 6? Reaction Products of Ca(0H) 2 with Clay Minerals ana Helatea oixicates 68 vi Page "Dry' 7 Compacted Mixtures at 60°C 68 owx'i/xng iwueriaid ••••••••• 68 Experimental Procedure 69 Slurry Mixtures at ^5°C 70 Starting Materials 70 Experimental Procedure 72 Dilute Suspension at 23°C 73 Procedures Used in Investigating the Properties of the Various Materials 7^- Analyses of Chemical Composition 74 X-ray Diffraction 7^ Differentlal Thermal Analysis 76 Infrared Absorption Spectroscopy 78 Electron Microscopy and Electron Diffraction 79 Determination of Surface Area by Water Vapor Adsorption 81 Cation Exchange Capacity 82 Determination of Zeta Potential and Sign of Surface Charge . 86 EXPERIMENTAL RESULTS 90 Well-Crystallized Tobermorites Prepared by Hydrothermal Synthesis 90 Unsubstituted Tobermorite §Q Preparation 90 Composition 90 X-ray Diffraction 90 Morphology 92 Differential Thermal Analysis 92 Infrared Absorption 92 Water Vapor Adsorption and Surface Area 97 Cation Exchange Capacity 98 Zeta Potential and Sign of Surface Charge 98 Plasticity of the Tobermorlte-Water System 100 Effect of Glycerol on Basal Spacing 101 The Effect of Lattice Substitution on the Properties of Tobermorite 102 Introduction and Notation 102 "Preparation of Substituted Tobermorites 103 X-ray Diffraction Characteristics of Substituted Tobermorites 106 Differential Thermal Analysis and Thermal Transformations 112 Morphology of Substituted Tobermorites 116 Infrared Spectra of Substituted Tobermorites .... 120 The Effect of Substitution on the Surface .-irea of Tobermorite 123 The Effect of Substitution on the Properties of the Tobermorite-Water Surface 125 Cation Exchange Capacity Measurements 131 Zeta Potential and Surface Charge of Substituted Tobermorites 135 vil Page Summary of Experimental Results on Well-Crystallized Tobermorites ...... 135 Poorly Crystallized Calcium Silicate Hydrates Prepared at Room Temperature - CSH(I) 137 Preparation and Designation of Products 137 Composition 136 X-ray Diffraction ' IkQ Morphology # , 1^4 Different iax raernai analysis . 147 Infrared Spectra 148 Surface Area and Water-Vapor Adsorption 153 Cation Exchange Capacities 157 Zeta Potential 159 Summary • . 160 Calcium Silicate Hydrates Produced by Hydration of C S and C S $ 2 3 162 Origin and Composition ..... 162 X-ray Diffraction Results 162 Morphology 166 Differential Thermal Analysis 169 Infrared Absorption 172 Surface Area 175 Cation Exchange Capacity 175 Zeta Potential and Surface Charge 176 Summary 177 Products of Chemical Reaction Between Ca(OH) and Silicate Minerals at or Near Room Temperature . 178 Reactions of Compacted Mixtures at 60°C 176 Starting Materials, Reaction Conditions, and Methods of Examination of Products 178 Reaction Products of Quartz 1?8 Reaction Product