TITLE:
Pyro and Kinetic Studies of Barium Oxalate Crystals Grown in Agar Gel
AUTHORS:
Paresh V. Dalal, Kishor B. Saraf, Navinchandra G. Shimpi, Navneet R. Shah
KEYWORDS:
Barium Oxalate; Thermo-Gravimetric Analysis; Kinetic Studies; Thermodynamic Parameters
JOURNAL NAME:
Journal of Crystallization Process and Technology,
Vol.2 No.4,
October
17,
2012
ABSTRACT: Single crystals of barium oxalate have been grown using gel method at ambient temperature. Thermal characteristics and kinetic parameters of barium oxalate crystals were determined by thermo-gravimetric (TG) analysis under non-isothermal heating conditions. The pyrolysis experiments were performed with increasing temperature up-to 600℃ at heating rate of 5℃, 7℃ and 10℃ in nitrogen gas atmosphere. The pyrolysis curve showed that loss of mass took place mainly in the range of 220℃ - 400℃. At higher temperature there was a significant mass loss due to decomposition of oxalates. Ozawa and Coats & Redfern methods were used to determine the apparent activation energies of material degradation. The apparent activation energies for barium oxalate crystals were obtained 187.42 KJ·mol-1 and 185.4 KJ·mol-1 for the respective methods.