| Titre : | Thermal degradation of aqueous piperazine for CO2 capture. 1. effect of process conditions and comparison of thermal stability of CO2 capture amines (2012) |
| Auteurs : | Stephanie Anne Freeman, Auteur ; Gary Thomas Rochelle, Auteur |
| Type de document : | Article : texte imprimé |
| Dans : | Industrial & engineering chemistry research (Vol. 51 N° 22, Juin 2012) |
| Article en page(s) : | pp. 7719–7725 |
| Note générale : | Industrial chemistry |
| Langues : | Anglais |
| Tags : | Thermal degradation Aqueous piperazine stability |
| Résumé : | The effect of process conditions on the rate of thermal degradation of concentrated, aqueous piperazine (PZ) was investigated. At 150 °C, 8 m (m) PZ degrades with a first order rate constant, k1, of 6.1 × 10–9 s–1. Thermal degradation of 8 m PZ with 0.3 mol CO2/mol alkalinity demonstrated an Arrhenius dependence on temperature with an activation energy of 184 kJ/mol. Degradation at 175 °C was negligible with no dissolved CO2, while the k1 increased from 65 to 71 × 10–9 s–1 at 0.1 to 0.4 mol CO2/mol alkalinity and decreased to 24 × 10–9 s–1 at 0.47 mol CO2/mol alkalinity. In an industrial system with a simple stripper, losses due to thermal degradation are expected to be 0.043 mmol PZ/mol CO2 captured. In the case of a 2-stage flash, losses are expected to be only 0.0086 mmol PZ/mol CO2 captured. A Maximum Estimated Stripper Temperature (MEST) was calculated for a variety of amines to provide the same thermal degradation rate of MEA at 120 °C based on first order rate constants for amine loss during thermal degradation and the expected Arrhenius dependence on temperature for all amines. Substituted and unsubstituted 6-member amine rings were found to be the most thermally stable. |
| ISSN : | 0888-5885 |
| En ligne : | http://pubs.acs.org/doi/abs/10.1021/ie201916x |
