| Title |
Influence of Ce3+ on the formation of α-semi-hydrate gypsum |
| Another Title |
Ce3+ įtaka α-pusvandenio gipso susidarymui. |
| Authors |
Kybartienė, Nora ; Leškevičienė, Violeta ; Valančius, Zenonas |
| DOI |
10.5755/j01.ms.18.4.3102 |
| Full Text |
|
| Is Part of |
Materials science = Medžiagotyra.. Kaunas : KTU. 2012, vol. 18, no. 4, p. 385-389.. ISSN 1392-1320. eISSN 2029-7289 |
| Keywords [eng] |
Gypsum ; α-semi-hydrate gypsum ; Cerium sulphate octahydrate ; Dehydration ; Crystal morphology |
| Abstract [eng] |
Influence of Ce3+ on the formation of α-semi-hydrate gypsum was investigated in this work. α-semi-hydrate gypsum is normally obtained by heat conversion of the dihydrate gypsum. The model system: CaSO4·2H2O–Ce2(SO4)3⋅8H2O was designed. The amount of Ce2(SO4)3⋅8H2O corresponding to 0.1; 0.5 and 1 % of Ce2O3 from the mass of dry materials (gypsum) was added to solution. Maleic anhydride (C4H2O3) was used as crystal modifier and 0.1 % of C4H2O3 from the mass of dry materials (gypsum) was added to solution. Water/gypsum of the suspension was equal to 2. The system was processed under hydrothermal conditions at 128 °C ±2 °C and 138 °C ±2 °C temperature; the duration of isothermal curing was 3 hours. The product obtained was treated at 400 °C temperature. The X-ray powder diffraction (XRD), Fouriertransform infrared spectroscopy (FT-IR) scanning electron microscopy (SEM) was used to characterize the product. The results showed that the larger amount of Ce3+ in the system, the larger the remaining amount of un-dehydrated dihydrate gypsum in the final product, and the resulting crystals of α-semi-hydrate gypsum are tiny, indefinite and irregular in shape. Therefore, the results obtained lead to a conclusion that Ce3+ has a negative influence on the dehydration of dihydrate gypsum (or on the formation of α-semi-hydrate gypsum) and the morphology of α-semihydrate gypsum crystals. |
| Published |
Kaunas : KTU |
| Type |
Journal article |
| Language |
English |
| Publication date |
2012 |
| CC license |
|