Binding and leaching of trace elements in Portland cement pastes
| Autor: | Anya Vollpracht, Wolfgang Brameshuber |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Cement
Ettringite Materials science Chromate conversion coating Metallurgy Inorganic chemistry technology industry and agriculture 0211 other engineering and technologies chemistry.chemical_element Vanadium Barium 02 engineering and technology Building and Construction 010501 environmental sciences 01 natural sciences law.invention Portland cement chemistry.chemical_compound chemistry law 021105 building & construction General Materials Science Leaching (metallurgy) Sulfate 0105 earth and related environmental sciences |
| Zdroj: | Cement and Concrete Research. 79:76-92 |
| ISSN: | 0008-8846 |
| Popis: | Portland cement contains trace elements originating from the raw materials and the fuels used for cement production. The trace elements are bound to some extent during cement hydration. A small fraction remains dissolved in the pore solution. The dissolved fractions of antimony, barium, chromium, lead, molybdenum and vanadium were quantified in the course of hydration of four different Portland cements. The development of heavy metal concentrations signifies the relevant hydration products for the binding of heavy metals. For chromate and molybdate a substitution for sulfate in ettringite was found. Vanadium and antimony are most likely not bound in ettringite. Barium precipitates as barium sulfate. For lead no clear trends could be observed. Leaching experiments were carried out and the concentrations of the leachates were compared to pore solution concentrations to check if the solubility of the heavy metals is relevant or if the leaching process is controlled by diffusion. |
| Databáze: | OpenAIRE |
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