Studies of dehydration kinetics of Li2SO4·H2O by the master plots method

• Authors: Tang Wanjun , Chen Donghua
• Languages of publication: EN

Abstracts

EN

The kinetics of Li2SO4·H2O dehydration in static air atmosphere was studied on the basis of nonisothermal measurements by differential scanning calorimetry. Dehydration data were subjected to an integral composite procedure, which includes an isoconversional method, a master plots method and a model-fitting method. Avrami-Erofeev equation was found to describe all the experimental data in the range of conversion degrees from 0.1 to 0.9. The determined activation energy equals 65.45 kJ·mol−1 with standard deviation ±0.47 kJ·mol−1. The estimated value of parameter m in Avrami-Erofeev equation is 2.15 with standard deviation ±0.11. Also, the obtained pre-exponential factor is 7.79×105 s−1 with standard deviation ±0.55×105 s−1. The results show that the present integral composite procedure gives self-consistent kinetic parameters.

Keywords

EN

Differential scanning calorimetry; dehydration; kinetics; master plots method; Li2SO4·H2O

• Publisher: De Gruyter Open
• Journal: Open Chemistry
• Year: 2007
• Volume: 5
• Issue: 1
• Pages: 341-348

Dates

published

1 - 3 - 2007

online

1 - 3 - 2007

Contributors

author

Tang Wanjun

• Hubei Key Laboratory for Catalysis & Material Science, College of Chemistry & Material Science, South-Central University for Nationalities, Wuhan, 430074, China

author

Chen Donghua

• Hubei Key Laboratory for Catalysis & Material Science, College of Chemistry & Material Science, South-Central University for Nationalities, Wuhan, 430074, China

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Identifiers

DOI

10.2478/s11532-006-0049-6