Dakhane Akash, Madavarapu Sateesh Babu, Marzke Robert, Neithalath Narayanan
1 School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, AZ, USA.
2 Department of Physics, Arizona State University, Tempe, AZ, USA.
Appl Spectrosc. 2017 Aug;71(8):1795-1807. doi: 10.1177/0003702817704588. Epub 2017 Apr 28.
The use of waste/by-product materials, such as slag or fly ash, activated using alkaline agents to create binding materials for construction applications (in lieu of portland cement) is on the rise. The influence of activation parameters (SiO to NaO ratio or M of the activator, NaO to slag ratio or n, cation type K or Na) on the process and extent of alkali activation of slag under ambient and elevated temperature curing, evaluated through spectroscopic techniques, is reported in this paper. Fourier transform infrared spectroscopy along with a Fourier self-deconvolution method is used. The major spectral band of interest lies in the wavenumber range of ∼950 cm, corresponding to the antisymmetric stretching vibration of Si-O-T (T = Si or Al) bonds. The variation in the spectra with time from 6 h to 28 days is attributed to the incorporation of Al in the gel structure and the enhancement in degree of polymerization of the gel. Si nuclear magnetic resonance spectroscopy is used to quantify the Al incorporation with time, which is found to be higher when Na silicate is used as the activator. The Si-O-T bond wavenumbers are also generally lower for the Na silicate activated systems.
使用诸如矿渣或粉煤灰等废弃物/副产品材料，通过碱性试剂活化以制造用于建筑应用的粘结材料（替代波特兰水泥）的情况正在增加。本文报道了通过光谱技术评估活化参数（活化剂的SiO与NaO比或M、NaO与矿渣比或n、阳离子类型K或Na）对常温及高温养护下矿渣碱活化过程和程度的影响。采用了傅里叶变换红外光谱法以及傅里叶自去卷积方法。主要关注的光谱带位于约950 cm的波数范围内，对应于Si - O - T（T = Si或Al）键的反对称伸缩振动。从6小时到28天光谱随时间的变化归因于Al掺入凝胶结构以及凝胶聚合度的提高。使用Si核磁共振光谱法定量随时间的Al掺入情况，发现当使用硅酸钠作为活化剂时Al掺入量更高。对于硅酸钠活化体系，Si - O - T键的波数通常也更低。
