Article ID Journal Published Year Pages File Type
1457795 Cement and Concrete Research 2007 6 Pages PDF
Abstract

This paper deals with the behaviour of calcium sulfoaluminate cement hydrated in presence of high concentration of soluble chromium salts (65 g/kg): chromium nitrate and sodium chromate. Chromium nitrate was chosen to verify the good retention of Cr3+ by calcium sulfoaluminate cement. Sodium chromate was employed to assess the ability of calcium sulfoaluminate to immobilize Cr6+.Leaching tests were carried out on two types of calcium sulfoaluminate cement containing 20% and 30% phosphogypsum, respectively. The microstructure was also investigated at 28 and 90 days.The results obtained point two main findings: –the retention of Cr3+ is excellent (> 99%), regardless of the type of cement,–the retention of Cr6+ depends on the type of cement and, in this case, the U phase is detected and promotes some expansion leading to cracking of the matrix.

Related Topics
Physical Sciences and Engineering Engineering Industrial and Manufacturing Engineering
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