Keggin-Al13改性C-A-S-H凝胶微观机理及其提升硅铝质玻璃体胶凝性能的基础研究

Aluminosilicate glass is the main composition of many industrial wastes with large volumes. Promoting its hydraulic reactivity and enhancing its binding performance is the key technology for consuming capacities of cement industry to industrial wates. The project is aimed at the fundamental theory on promoting the hydraulic efficiency of aluminosilcate glass by adding five-coordinated aluminum that modifies the molecular and nano-micro structure of the C-A-S-H gel, by using the superatom material Keggin-Al13 as the innovative modification materails for the target of promoting the hydraulic reactivity of glass. The research starts with analysis on the hydrolysis process and properties of the products of Keggin-Al13, uses advanced techniques including NMR, XPS, FE-SEM and SPM to investigate the microstructural modification mechanism of five-coordinated aluminum to the structure of C-A-S-H gel, to study the relation between the transport capabability of C-A-S-H gel and its structure, and to establish the theoretical links between the gel properties and the corrosion process of glass. A new theory on promoting the hydraulic efficiency and enhancing the binding performance of aluminosilicate glass will be established. The research uses new material to modify the traditional cementitious materials, develops a new theory on promoting the binding performance of cement containing industrial wastes, and adds to the knowledge on cement chemistry and concrete science.

硅铝质玻璃体是多种大宗工业废渣的主要成分，提升其水化活性以增强胶凝能力是提升水泥工业消纳工业废渣效率的关键技术。项目针对外掺五配位铝改性C-A-S-H凝胶分子和纳微结构并提升硅铝质玻璃体水化效率的微观机理这一基础理论问题，以超原子材料Keggin-Al13为创新改性材料，面向硅铝质玻璃体水化活性提升的目标，从Keggin-Al13水解过程和产物性状研究出发，运用NMR、XPS、FE-SEM、SPM等多种先进技术论证水解五配位铝改性C-A-S-H凝胶结构的微观机制，论证C-A-S-H凝胶结构与其离子传输能力的关系，揭示凝胶性质与玻璃体溶蚀过程的理论联系，发展硅铝质玻璃体水化效率强化和胶凝性能提升的新理论。项目研究采用新材料改造传统水泥基材料，发展一种全新的含工业废渣水泥胶凝性能提升理论，并成为水泥化学和混凝土科学新增知识点。

水泥工业消纳硅铝质玻璃体废渣的关键是提升硅铝质玻璃体的水化活性以增强其胶凝能力。针对玻璃体后期水化产物结构致密抑制离子传输，制约玻璃体水化程度提升的问题，本项目提出无机超分子材料Keggin-Al13调控水化产物纳微观结构以增强硅铝质玻璃体溶解反应速率，并提升含工业废渣水泥胶凝性能的关键理论。.本项目采用先进的聚焦双束扫描电镜系统（FIB plus SEM）精确定位矿粉颗粒及内部水化产物位置，制备透射电镜（TEM）样品，提出原位研究矿渣颗粒水化产物纳微结构演变的新方法。基于此方法，本项目提出Keggin-Al13调控矿渣内部水化产物纳微结构以提升矿渣后期反应程度的微观机理。本项目理论研究成果成功应用于大掺量矿渣低碳高性能矿山回填胶凝材料制备技术，取得良好的经济效益和社会价值。. 本项目主要创新性研究成果如下：. （1）本论文发现矿粉颗粒内部产物区呈现分层结构，即产物相水化硅铝酸钙凝胶（C-A-S-H）和层状双氢氧化物（LDHs）晶体的定向分布。外侧富集结晶良好的LDHs晶体，形貌疏松多孔；内侧为C-A-S-H凝胶和结晶差的LDHs相的混合物，形貌致密。致密的C-A-S-H凝胶产物层孔隙率低，抑制溶出离子在内部产物区传输，制约玻璃相水化程度。调控内侧致密C-A-S-H凝胶产物层的结构为提升矿粉颗粒后期水化程度的理论基础。. （2）Keggin-Al13调控矿粉颗粒内部产物区LDHs晶体生长，避免生成致密的C-A-S-H凝胶产物层，使内部水化产物区结构疏松多孔。削弱内部水化产物层对溶出离子传输的抑制作用，促进未反应矿粉颗粒与水化产物间的离子传输。. 本项目研究提出Keggin-Al13调控玻璃相水化过程的新理论，实现工业废弃物资源化综合利用效率提升，为我国工业废弃物处置及水泥低碳、环保、可持续性发展做出贡献。.