Mossbauer Effect Study of the Hyper fine Structure of the Different Phases of Iron in the Portland Cement Produced in Qatar

Abstract

Various samples of the raw materials used in the manufacture of Portland cement in Qatar, the clinker produced and the cement itself were studied by using Mossbauer Effect and X-ray diffraction analysis in order to investigate the hyperfine structure of the iron forms present and the distribution of these forms among the different phases of the cement. The results obtained revealed the presence of five forms of iron in the cement clinker (a) Fe3"1" ions in octahedral sites existed in the ferrite phase (C4AF). (b) Three forms of iron were found in the tricalcium silicate solid solution (alite); these are: Fe2"1" in tetrahedral sites, Fe3'1' in tetrahedral sites and Fe3"1" in octahedral sites, (c) The fifth form of iron was fo.und in the belite phase (ft - C^S) as a lattice stabilizer and occupies a low-spin state Fe^ in octahedral rite. The content of each form was referred to the total iron present in the cement.