对小离子添加剂对Mg-酸盐水合物核化影响的洞察
Annika Bastian1, Yannick Hermann Emminger1, Nour Kerdieh1
1Department of Physical Chemistry, University of Konstanz, 78457 Konstanz, Germany.
The Journal of chemical physics
|February 12, 2025
概括
酸 (MS) 水泥使用酸水合物 (M-S-H) 作为粘合剂. 酸盐和碳酸盐等离子添加剂通过减少超和而改善M-S-H形成,而不会阻碍早期生长.
科学领域:
- 材料科学 材料科学 材料科学
- 无机化学 无机化学
- 可持续的建筑材料 可持续的建筑材料
背景情况:
- 酸 (MS) 水泥为波特兰水泥提供了一个低碳的替代品,利用酸水合物 (M-S-H) 作为主要的结合阶段.
- 缓慢的MgO溶解限制了Mg离子的释放,阻碍了M-S-H的形成,需要提高MgO溶解和Mg离子的可用性.
研究的目的:
- 系统地研究四种离子添加剂 (乙酸盐,酸盐,正酸盐,碳酸盐) 对M-S-H核和早期生长的影响.
- 评估这些添加剂通过复合Mg2+和促进MgO溶解而促进M-S-H形成的潜力,而不妨碍M-S-H的发展.
主要方法:
- 开发了一种高度可重现的结晶场景,以研究阳离子添加剂对M-S-H核和生长的影响.
- 这项研究分析了酸盐,酸盐,正酸盐和碳酸盐对Mg离子超和M-S-H形成动学的影响.
主要成果:
- -阳离子复合物可能积极参与M-S-H核化,可能使低超度水平的形成成为可能.
- 虽然酸盐没有抑制核化,但它显著减缓了M-S-H的生长,可能会影响水泥强度.
- 中等度的酸盐和碳酸盐对M-S-H形成的影响最小,同时可能减少核超和.
结论:
- 酸盐和碳酸盐在研究的离子中显示出增强MS水泥性能的最大潜力,因为它们对MSH核和生长的平衡作用.
- 需要进一步的研究,以充分阐明这些离子和MSH形成之间的复杂相互作用,以优化低碳水泥应用.
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