Copper and cobalt improve the acid resistance of alkali-activated cements
Copper and cobalt improve the acid resistance of alkali-activated cements
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DOI：
10.1016/j.cemconres.2018.08.002
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发表时间：
2019-01-01
影响因子：
11.4
通讯作者：
Srubar, Wil V., III
中科院分区：
文献类型：
--
作者：
Gevaudan, Juan Pablo;Caicedo-Ramirez, Alejandro;Srubar, Wil V., III
本文提出了一种新的掺铜钴碱水泥酸降解机理的实验证据。Cu和Co掺入到二元偏高岭土和碱性氧气炉（BOF）炉渣为基础的活性炭减少体积渗透孔隙率和酸渗透，并推迟硫酸钙相的形成后，暴露于酸。使用X射线衍射和电子探针分析（EMPA）的微观结构演变和元素迁移率的分析表明，铜和钴掺杂与AAC浸出模式的主要差异，当暴露于硫酸。汇聚的证据线表明，通过Cu和Co的优先移动以及沿着其它多价阳离子（即，镁），在酸降解前沿，稳定AAC粘合剂并抑制进一步劣化。
Experimental evidence of a new acid degradation mechanism in alkali-activated cements (AACs) micro-doped with copper (Cu) and cobalt (Co) is presented in this work. Cu and Co incorporation into binary metakaolin and basic oxygen furnace (BOF) slag-based AACs reduced bulk permeable porosity and acid penetration and retarded the formation of calcium sulfate phases upon exposure to acid. Analysis of microstructural evolution and elemental mobility using X-ray diffraction and electron microprobe analysis (EMPA) showed that Cu and Co doping was associated with major differences in AAC leaching patterns when exposed to sulfuric acid. Converging lines of evidence suggest that acid resistance is improved by the preferential mobilization of Cu and Co, along with other multivalent cations (i.e., magnesium), at the acid degradation front(s), stabilizing the AAC binder and inhibiting further deterioration.