A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Reaction mechanisms, kinetics, and nanostructural evolution of magnesium silicate hydrate (M-S-H) gels
Abstract M-S-H gels were synthesised via reaction of Mg(OH)2 with silica fume, cured at 35 °C for up to 112 days, and their chemical and nanostructural evolution was examined. M-S-H gels with structural similarity to the thermodynamically stable serpentine-group mineral lizardite were formed. Quantification of 25Mg and 29Si MAS and 1H 29Si CPMAS NMR, electron microscopy, and thermogravimetric data showed dissolution of brucite and silica fume, and M-S-H formation, all occurred linearly with time up to 56 days. Data showed strong correlation with the Avrami-Erofeyey nucleation kinetic model, indicating M-S-H formation was governed by nucleation reactions. After 112 days, two distinct M-S-H gels were formed: a Si-rich M-S-H gel with molar Mg/Si = 0.55(±0.2), and a Mg-rich M-S-H gel with molar Mg/Si = 0.80(±0.5). Nanostructural rearrangement of M-S-H continues up to 112 days, with increased crosslinking and polymerisation. This new insight is important for application of M-S-H binders in both construction and radioactive/toxic waste immobilisation.
Reaction mechanisms, kinetics, and nanostructural evolution of magnesium silicate hydrate (M-S-H) gels
Abstract M-S-H gels were synthesised via reaction of Mg(OH)2 with silica fume, cured at 35 °C for up to 112 days, and their chemical and nanostructural evolution was examined. M-S-H gels with structural similarity to the thermodynamically stable serpentine-group mineral lizardite were formed. Quantification of 25Mg and 29Si MAS and 1H 29Si CPMAS NMR, electron microscopy, and thermogravimetric data showed dissolution of brucite and silica fume, and M-S-H formation, all occurred linearly with time up to 56 days. Data showed strong correlation with the Avrami-Erofeyey nucleation kinetic model, indicating M-S-H formation was governed by nucleation reactions. After 112 days, two distinct M-S-H gels were formed: a Si-rich M-S-H gel with molar Mg/Si = 0.55(±0.2), and a Mg-rich M-S-H gel with molar Mg/Si = 0.80(±0.5). Nanostructural rearrangement of M-S-H continues up to 112 days, with increased crosslinking and polymerisation. This new insight is important for application of M-S-H binders in both construction and radioactive/toxic waste immobilisation.
Reaction mechanisms, kinetics, and nanostructural evolution of magnesium silicate hydrate (M-S-H) gels
Simoni, Marco (author) / Woo, Chun Long (author) / Zhao, Han (author) / Iuga, Dinu (author) / Svora, Petr (author) / Hanein, Theodore (author) / Kinoshita, Hajime (author) / Walkley, Brant (author)
2023-08-01
Article (Journal)
Electronic Resource
English
Synthesis and characterisation of magnesium silicate hydrate gels
| Online Contents | 2005
Synthesis and characterisation of magnesium silicate hydrate gels
| Tema Archive | 2005
Synthesis and characterisation of magnesium silicate hydrate gels
| British Library Online Contents | 2005
Synthesis and characterisation of magnesium silicate hydrate gels
| Elsevier | 2004
Multiscale structure of calcium- and magnesium-silicate-hydrate gels
| Tema Archive | 2014