Martín-Rodríguez, P.; Fernández-Jiménez, A.; Alonso, M.M.; Palomo, A.; García-Lodeiro, I. Valorisation of “La Palma” Volcanic Ash for Making Portland-Blended, Alkaline and Hybrid Portland–Alkaline Cements. Materials2024, 17, 242.
Martín-Rodríguez, P.; Fernández-Jiménez, A.; Alonso, M.M.; Palomo, A.; García-Lodeiro, I. Valorisation of “La Palma” Volcanic Ash for Making Portland-Blended, Alkaline and Hybrid Portland–Alkaline Cements. Materials 2024, 17, 242.
Martín-Rodríguez, P.; Fernández-Jiménez, A.; Alonso, M.M.; Palomo, A.; García-Lodeiro, I. Valorisation of “La Palma” Volcanic Ash for Making Portland-Blended, Alkaline and Hybrid Portland–Alkaline Cements. Materials2024, 17, 242.
Martín-Rodríguez, P.; Fernández-Jiménez, A.; Alonso, M.M.; Palomo, A.; García-Lodeiro, I. Valorisation of “La Palma” Volcanic Ash for Making Portland-Blended, Alkaline and Hybrid Portland–Alkaline Cements. Materials 2024, 17, 242.
Abstract
Abstract: The present work evaluates the feasibility of using volcanic fly ash (VFA), generated by the eruption of the Tajogaite volcano on the island of La Palma (Spain) in 2021, as a precursor in the preparation of cementitious materials with different Portland cement (PC) replacement levels (0%, 30%, 70% and 100%), in the absence (Blended Cement, BC) and presence of an alkaline ac-tivator (Hybrid Alkaline Cement, HAC, and Alkaline Cements, AC). Hydration kinetics (isother-mal conduction calorimetry), paste mechanical strengths and reaction products were character-ised by XRD, FTIR, TG/DTG and BSEM/EDX. The results obtained indicate that the strengths de-veloped by the hybrid alkaline cements (HAC) are higher than those of the blended cements (BC), especially at the age of 2 days, where 25 MPa was obtained with the replacement of 70% PC by VFA. Alkaline cements (AC, 100% VFA) prepared with 8M NaOH solution as activator reached 40 MPa after 2 days. It was observed that in all the binders, depending on the initial composition of the binder mixture and the percentage of replacement and/or activator, VFA reacts to form cementitious gels, C-A-S-H and N-A-S-H type, which supports its use as a mineral addition to blended cement or as a precursor in the preparation of alkaline and hybrid alkaline cements.
Chemistry and Materials Science, Materials Science and Technology
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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