Premium
Sucrose retards the reaction of non‐calcium geopolymers: An implication for developing kinetics‐controlling admixtures
Author(s) -
Chen Xu,
Mondal Paramita
Publication year - 2021
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/jace.17706
Subject(s) - metakaolin , geopolymer , chemical engineering , calcium aluminosilicate , sodium silicate , sucrose , aluminosilicate , chemistry , dissolution , calcium , materials science , kinetics , portland cement , calcium silicate , inorganic chemistry , cement , organic chemistry , fly ash , composite material , catalysis , physics , quantum mechanics , engineering
For geopolymers (no or low calcium), the chemical admixtures designed for ordinary portland cement are either inefficient or ineffective. In this study, the effects of sucrose on the kinetics of geopolymerization (no calcium) were investigated. From calorimetry tests, we found sucrose retarded the geopolymerization of sodium silicate‐activated metakaolin. This retardation is unlikely to be related to the dissolution of metakaolin, since sucrose also hindered the reaction of the synthetic gel (no metakaolin) as evidenced by the smaller particle sizes under microscopy. Further spectroscopy and total organic carbon (TOC) tests indicated that sucrose did not adsorb or chemically interact with the synthetic aluminosilicate gel and the intermediate (alumino)silicate species. In contrast, the retardation mechanism was found to be due to the interaction of sucrose with alkalis in the solution, partially based on the structural characterization of sucrose under alkaline condition. To the best of our knowledge, this work is the first of its type to explore and understand the reaction‐controlling admixtures for non‐calcium geopolymers.