Kinetics of sodium bicarbonate decomposition

✍ Scribed by Wang Hu; J. M. Smith; Timur Doǧu; Gülsen Doǧu

• Publisher: American Institute of Chemical Engineers
• Year: 1986
• Tongue: English
• Weight: 520 KB
• Volume: 32
• Category: Article
• ISSN: 0001-1541
• DOI: 10.1002/aic.690320909

✦ Synopsis

Kinetics of Sodium Bicarbonate Decomposition

A thermal gravimetric method was used to measure rates of decomposition of NAHCO, particles. Such decomposition produces a highly porous Na,Co, that reacts with SO, rapidly and completely at moderate temperatures. Hence, NaHCO, decomposition provides a reactant with attractive features for SO, removal. The rapid rate of decomposition combined with the high heat effect prevented determining intrinsic rates by constant temperature runs when the temperature level was above 400 K. However, rising-temperature runs, which allowed time for heat transfer to equilibrate temperatures of the thermocouple and particles, gave reliable results at high temperatures. The activation energy was 102 kJ/mol. Porosimeter data verified the large increase in pore volume (from 0.03 to 0.39 x lo-, m3/kg) on converting the NaHCO, particles to Na,CO,.

First-order kinetics were observed up to high conversions, after which the apparent order decreased. However, the sodium bicarbonate could be completely converted to Na,CO,.