聚合物
材料科学
胶凝的
煅烧
煤矸石
微观结构
粉煤灰
复合数
化学工程
复合材料
硅酸钠
多孔性
抗压强度
煤
冶金
水泥
废物管理
化学
催化作用
生物化学
工程类
作者
Yanbing Zhao,Caiqian Yang,Kefeng Li,Qu Feng,Chengyu Yan,Zhiren Wu
标识
DOI:10.1016/j.conbuildmat.2021.125999
摘要
The feasibility of coal gangue as primary cementitious material was experimentally investigated in this paper. An Orthogonal method was employed to investigate the optimum activation strategy for coal gangue-based geopolymer. Experiment parameters included the modulus of sodium silicate (M), alkali content (A), calcination temperature (T), holding time (H), and water-to-binder ratio (W/B). Meanwhile, the phase transitions, chemical compositions, and microstructure evolution were investigated by supplementary techniques, such as ESEM, XRD, and FTIR. Experimental results indicated that the hydration reactivity of coal gangue was markedly enhanced. And the formations of high contents of amorphous SiO2 and Al2O3 phases are the critical factors for the high reactivity, which highly depends on the proper calcination temperature and holding time. The hydration productions of alkali-activated coal gangue, mainly N-A-S-H gels, can rapidly precipitate around the unreacted particles and fill the existing cavities. Meanwhile, the average surface area, diameter, and porosity considerably declined with the hydration degree of geopolymer. In summary, coal gangue can be viewed as a new eco-friendly cementitious material via the proposed composite activation strategy.
科研通智能强力驱动
Strongly Powered by AbleSci AI