2026-05-30T10:55:40Zhttps://riuma.uma.es/rest/oai/request

oai:riuma.uma.es:10630/290782026-02-03T11:20:36Zcom_10630_2254col_10630_37953

Hydration Activation of Alite-Belite-Ye’elimite Cements by Doping with Boron Zea-Garcia, Jesus D. Sanfélix, Susana G. Vallcorba, Oriol García-Aranda, Miguel Ángel Santacruz-Cruz, María Isabel Gómez-de-la-Torre, María de los Ángeles Cemento The hydration behavior of two alite-belite-ye’elimite (ABY) cements has been studied. The production of these materials releases into atmosphere ∼17% less CO2 compared to Portland cement. The ABY cement contains alite, β-C2S, and ye’elimite as main phases, while dABY (activated by adding borax) contains not only these three phases but also α′H-C2S. The role of boron in these systems is 2-fold: (i) acting as a retarder at early hydration ages since the precipitation of AH3 gel has been delayed from over 4 h in ABY to over 24 h in dABY; and (ii) as an activator at late hydration ages by stabilizing highly reactive β- and α′H-belites. The degree of hydration of β-C2S in ABY is 42% at 28 days, while that of β-C2S and α′H-C2S in dABY at the same age is 80 and 88%, respectively. Moreover, the main hydration products in both systems are ettringite and C−S−H gel. The local structure of these hydrated products has been studied by 27Al and 29Si magic angle spinning nuclear magnetic resonance (MAS−NMR) and found to be similar in both cements. However, the amount of C−S−H gel is 63% of all silicon-bearing phases in ABY after 28 days while it is 76% (determined by 29Si MAS−NMR) in dABY, which justifies the higher mechanical strengths of dABY mortars. 2024-01-24T07:00:27Z 2024-01-24T07:00:27Z 2020 journal article ACS Sustainable Chem. Eng. 2020, 8, 3583−3590 https://hdl.handle.net/10630/29078 https://dx.doi.org/10.1021/acssuschemeng.9b05975 spa http://creativecommons.org/licenses/by-nc-nd/4.0/ open access Attribution-NonCommercial-NoDerivatives 4.0 Internacional