Thermal decomposition of europium sulfates Eu2(SO4)3·8H2O and EuSO4
| Autor: | A.A. Polkovnikov, S.A. Basova, E.I. Sal’nikova, Yu. G. Denisenko, Oleg V. Andreev, Nikolay A. Khritokhin |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Inorganic chemistry
Enthalpy chemistry.chemical_element 02 engineering and technology 010402 general chemistry 01 natural sciences law.invention Inorganic Chemistry chemistry.chemical_compound law Materials Chemistry Physical and Theoretical Chemistry Sulfate Crystallization Thermal analysis Chemical decomposition Chemistry Thermal decomposition 021001 nanoscience & nanotechnology Condensed Matter Physics Decomposition 0104 chemical sciences Electronic Optical and Magnetic Materials Ceramics and Composites 0210 nano-technology Europium |
| Zdroj: | Journal of Solid State Chemistry. 255:219-224 |
| ISSN: | 0022-4596 |
| Popis: | Reactions of europium sulfates Eu 2 (SO 4 ) 3 ·8H 2 O and EuSO 4 complete decomposition were studied by Simultaneous Thermal Analysis. It was revealed that one-step dehydratation of Eu 2 (SO 4 ) 3 ·8H 2 O crystallohydrate is accompanied by the formation of amorphous anhydrous europium sulfate Eu 2 (SO 4 ) 3 . Crystallization of amorphous europium (III) sulfate occurs at 381.1 °С (in argon) and 391.3 °C (in air). The average enthalpy values for dehydratation reaction of Eu 2 (SO 4 ) 3 ·8H 2 O (ΔH° = 141.1 kJ/mol), decomposition reactions of Eu 2 (SO 4 ) 3 (ΔH = 463.1 kJ/mol), Eu 2 O 2 SO 4 (ΔH = 378.4 kJ/mol) and EuSO 4 (ΔH = 124.1 kJ/mol) were determined. The step process mechanisms of thermal decomposition of europium (III) sulfate in air and europium (II) sulfate in inert atmosphere were established and justified. The kinetic parameters of complete thermal decomposition of europium (III) sulfate octahydrate were calculated by Kissinger model. The standard enthalpies of compound formation were calculated using thermal effects and formation enthalpy data for binary compounds. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect