Article
Materials Science, Multidisciplinary
Gen-ichiro Yamamoto, Atsushi Kyono, Satoru Okada
Summary: Dypingite is a common phase of crystalline magnesium carbonate hydrates and its thermal transformation process was studied using high-temperature X-ray diffraction and synchrotron X-ray scattering. Dypingite transforms to hydromagnesite below 100 degrees C, while an amorphous phase is predominant at 250-350 degrees C, and crystallizes to MgO at 400 degrees C. Despite its similar local structure to hydromagnesite, dypingite exhibits a different thermal transformation pathway.
Article
Construction & Building Technology
Rakibul I. Khan, Salman Siddique, Warda Ashraf
Summary: This study investigates the mechanical and microstructural properties of carbonated composites produced using slag, wollastonite, and magnesia. The results show that the formation of hydrated magnesium carbonates increases the density of the carbonated matrix. The addition of magnesia also changes the pore size distribution and enhances the compressive strength.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Crystallography
Sirine Guermech, Julien Mocellin, Lan-Huong Tran, Guy Mercier, Louis-Cesar Pasquier
Summary: This study investigates the precipitation step of carbonation of serpentine mining wastes using actual carbonated solution. The results show that increasing temperature accelerates precipitation kinetics and higher supersaturation promotes better reaction yield. The grain sizes of the resulting minerals differ from those obtained in synthetic solutions.
JOURNAL OF CRYSTAL GROWTH
(2022)
Article
Architecture
Yong-Taek Lim, Seung-Young So, Hong-Seok Jang
Summary: The study investigated the effects of calcination temperature on the physical properties of light-burned MgO and carbonates formation. Results showed that the crystal size of light-burned MgO increased with calcination temperature, while carbonate formation decreased with increasing crystal size. Additionally, different carbonate phases formed at different calcination temperatures, with nesquehonite and hydromagnesite identified in the specimens. The highest compressive strength was observed in the specimen with nesquehonite, while hydromagnesite exhibited better CO2 sequestration capacity.
JOURNAL OF ASIAN ARCHITECTURE AND BUILDING ENGINEERING
(2022)
Article
Materials Science, Multidisciplinary
Gen-ichiro Yamamoto, Atsushi Kyono, Satoru Okada
Summary: This study investigates the nature of amorphous magnesium carbonate (AMC) formed during the crystallization and decomposition of nesquehonite (NSQ) using X-ray diffraction and atomic pair distribution function methods. The results show that alkali cations in aqueous solutions significantly influence the crystallization of NSQ.
PHYSICS AND CHEMISTRY OF MINERALS
(2023)
Article
Construction & Building Technology
Graciela Ponce-Anton, Anna Arizzi, Giuseppe Cultrone, Maria Cruz Zuluaga, Luis Angel Ortega, Juantxo Agirre Mauleon
Summary: The mineralogical, chemical, and physical characterization of archaeological lime mortars at Amaiur Castle in Spain revealed that the mortars' durability is largely influenced by their textural features, with high porosity and water absorption contributing to susceptibility to deterioration. The identification of hydrotalcite and hydromagnesite in the mortar binder supports the traditional hot-mixing method used in manufacturing the mortars at the castle. This study provides valuable insights for formulating compatible repair mortars to ensure suitable conservation of the castle and similar ancient structures.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Geochemistry & Geophysics
Anna L. Harrison, Pascale Benezeth, Jacques Schott, Eric H. Oelkers, Vasileios Mavromatis
Summary: The experiment showed that at 25 and 35 degrees Celsius, nesquehonite transforms into dypingite through dissolution and re-precipitation, leading to significant exchange of Mg and C between solid and fluid. During the transformation, the initial isotopic composition of the solid phase was overwritten, indicating that isotopic equilibrium likely occurred between dypingite and fluid.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2021)
Article
Construction & Building Technology
Diogo Henrique de Bern, Priscila Ongaratto Trentin, Ronaldo A. Medeiros-Junior
Summary: Efflorescence formation in mortars with higher lime content was studied in this research. The results showed that increased lime content led to more efflorescence, reduced flexural tensile and compressive strength, increased water absorption by capillarity, and higher porosity of the mortars. Calcium carbonate was identified as the material formed by the efflorescence through microstructural tests. Users need to take extra precautions when using lime-cement mortars to prevent efflorescence.
INTERNATIONAL JOURNAL OF BUILDING PATHOLOGY AND ADAPTATION
(2022)
