The effect of magnesium on the structure of calcium aluminosilicate glasses

Samples of cemented magnesium turnings and Magnox alloy, simulating wasteforms that require re-work, have been thermally treated to produce largely glassy calcium magnesium aluminosilicate products. X-ray diffraction shows the presence of a variety of crystalline phases (Mg x Al 2–x O 4 phases, åkermanite-gehlenite phases and merwinite), as well as diffuse scattering characteristic of glassy material. Structural investigations using Raman spectroscopy show that the products contain amorphous aluminosilicate networks, with changes in the Q 2 and Q 1 species in the network with increasing metal content. These investigations also suggest a high number of [AlO 4 ] – tetrahedra are present in the network.