The effects of heat and mass transport on the results of thermal decomposition studies: Part 1. The three reactions of calcium oxalate monohydrate

摘要: Abstract The importance of heat and mass transfer was studied in the case three simple inorganic reactions (CaC 2 O 4 ·H ⇌ CaC + H O, → CaCO 3 CO CaO ) by thermogravimetry thermogravimetry-mass spectrometry. A “compensation effect” observed between heating rate sample mass: measured thermogravimetric curves did not change when increased decreased roughly same factor ranges 30–200°C/min 1–8 mg, respectively. This fact reveals a complete lack kinetic control casts doubt upon calculations based on shift decomposition temperature increase rate. Experiments at 4°C/min 0.5 mg proved that transport is also dominant rate-controlling process for irreversible second reaction.