Reactive recrystallization of sodium bicarbonate

Robert S. Gärtner*, Marcelo M. Seckler, Geert-Jan Witkamp

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

6 Scopus citations

Abstract

The thermal decomposition of sodium bicarbonate, NaHCO3, in mixed solvents composed of ethylene glycol and water was found to occur solution mediated; i.e., bicarbonate ions (HCO3-) convert in solution to carbonate ions (CO32-), carbon dioxide, and water. The equilibrium of this reaction shifts with increasing temperature toward the bicarbonate decomposition. Above 90 °C, the decomposition of the bicarbonate ions in solution results in the conversion (recrystallization) of solid NaHCO3(s) (nahcolite) in contact with the solution. This recrystallization of NaHCO3(s) at temperatures above 90 °C is independent of the water content for the tested mixed solvents. Thus, slurries of solid sodium bicarbonate (NaHCO3(s)) above 90 °C undergo a solution-mediated recrystallization via wegscheiderite (Na2CO 3·3NaHCO3(s))-as an intermediately formed solid phase-to sodium carbonate anhydrate (Na2CO3(s)). The decomposition rates were measured and the kinetics fitted to the most probable mechanism, i.e., first order in concentration of the bicarbonate ion in solution. Additionally, the solubility of nahcolite (NaHCO3(s)) was determined for a range of mixed solvent compositions and temperatures.

Original languageEnglish (US)
Pages (from-to)4272-4283
Number of pages12
JournalIndustrial and Engineering Chemistry Research
Volume44
Issue number12
DOIs
StatePublished - Jun 8 2005

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)
  • Industrial and Manufacturing Engineering

Fingerprint

Dive into the research topics of 'Reactive recrystallization of sodium bicarbonate'. Together they form a unique fingerprint.

Cite this