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

• Autorzy: Tang Wanjun , Chen Donghua
• Języki publikacji: EN

Abstrakty

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.

Słowa kluczowe

EN

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

• Czasopismo: Open Chemistry
• Rocznik: 2007
• Tom: 5
• Numer: 1
• Strony: 341-348

Daty

wydano

2007-03-01

online

2007-03-01

Twórcy

autor

Tang Wanjun

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

autor

Chen Donghua

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

Bibliografia

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Identyfikatory

DOI

10.2478/s11532-006-0049-6