Solidification of heavy metals in ettringite and its stability research

Author(s): Bei Wu, Xiang-guo Li, Baoguo Ma, Minglei Zhang
Paper category: Conference
Book title: 2nd International conference on Microstructural-related Durability of Cementitious Composites
Editor(s): Guang Ye, K. Van Breugel, Wei Sun, Changwen Miao
Print ISBN: 978-2-35158-129-2
e-ISBN: 978-2-35158-123-0
Publisher: RILEM Publications SARL
Pages: 1596- 1605
Total Pages: 9
Language: English

Abstract: 
Solidification threshold and stability of heavy metals in Ettringite dominated curing system was researched in the paper. Three criteria, hydration or damage degree tested by Xray diffraction (XRD) together with scanning electron microscopy (SEM) and leaching toxicity tested by toxicity characteristic leaching procedure(TCLP) according to Chinese national standard(HJ 557-2009) of samples doped with heavy metal ions such as Zn²⁺, Cu²⁺ and Pb²⁺, were proposed in the solidification threshold and stability studies. Considering test results from hydration degree and leaching toxicity of samples, solidification thresholds of Zn²⁺, Cu²⁺ and Pb²⁺ in Ettringite were around 1.32%, 2.2% and 6% (in mass), respectively. Heavy metal ions leaching concentration of samples after accelerated carbonation, acid and alkali corrosions or heating treatment respectively, were all far below the limits. It meant that the curing system had highly resistance to these simulated environments and was very stable.

Online publication: 2013
Publication Type: full_text
Public price (Euros): 0.00