Previously, the lack of a thermodynamic database for N-(C-)A-S-H gel limited the application of thermodynamic modeling to alkali-activated fly ash (AAFA). This study pioneers thermodynamic modeling of AAFA using a recently developed thermodynamic dataset for N-(C-)A-S-H gel. The reaction products, pore solutions and reaction kinetics of AAFA pastes were experimentally determined. Based on the reaction kinetics, the composition of the solid phases and the pore solution of AAFA were modeled over time. The results showed that the simulated compositions of the solid reaction products and pore solution match closely with the experimental results, especially for the sodium hydroxide-activated system. Moreover, modeling results point out the potential presence of minor reaction products (e.g., C-(N-)A-S-H gel, microcrystalline ferrihydrite, Mg-containing phases) undetectable by experimental techniques. The study also demonstrated that thermodynamic modeling accurately captured the amount of bound water in reaction products, highlighting its robustness in both qualitative and quantitative analysis.

中文翻译：

---

碱活化粉煤灰浆料的热力学建模


以前，缺乏 N-（C-）A-S-H 凝胶的热力学数据库限制了热力学建模在碱活化飞灰 （AAFA） 中的应用。本研究使用最近开发的 N-（C-）A-S-H 凝胶热力学数据集开创了 AAFA 的热力学建模。实验测定 AAFA 糊体的反应产物、孔隙溶液和反应动力学。基于反应动力学，对 AAFA 的固相组成和孔隙溶液随时间的变化进行建模。结果表明，固体反应产物和孔隙溶液的模拟组成与实验结果非常吻合，尤其是氢氧化钠活化体系。此外，建模结果指出可能存在实验技术无法检测到的微量反应产物（例如 C-（N-）A-S-H 凝胶、微晶水铁矿、含 Mg 相）。该研究还表明，热力学建模准确地捕获了反应产物中结合水的量，突出了其在定性和定量分析中的稳健性。