Abstract
Silicoaluminophosphates (SAPO-17, SAPO-35, SAPO-56 and SAPO-RHO) synthesised via hydrothermal means are tested for their abilities to adsorb carbon dioxide. These 8-ring microporous phosphates show high capacities to adsorb CO 2. SAPO-RHO has a high uptake of CO 2 and a very low uptake of N 2 due to its narrow pore window aperture at 273 K. Its significant uptake of N 2 at 77 K is rationalised by a temperature induced shrinkage effect. SAPO-56 has a slightly higher CO 2 capacity (5.42 mmol/g, 273 K, 101 kPa) and is less water sensitive than zeolite 13X. Cyclic adsorption and in situ infrared spectroscopy (IR) reveal that SAPOs retain 95% of their original CO 2 capacity after six cycles and that adsorption occurs via physisorption. The calculated heat of adsorption for CO 2 (at 0.2-0.7 mmol/g loading) on SAPO-56 and SAPO-RHO lies in the physisorption range (∼35 kJ/mol). SAPOs, in particular SAPO-56 and SAPO-RHO, possess many desirable properties and are potentially good adsorbents for CO 2 capture in swing adsorption processes.
| Original language | English |
|---|---|
| Pages (from-to) | 90-96 |
| Number of pages | 7 |
| Journal | Microporous and Mesoporous Materials |
| Volume | 156 |
| DOIs | |
| Publication status | Published - 1 Jul 2012 |
Keywords
- Adsorption
- Carbon capture
- Carbon dioxide
- SAPO-56
- Silicoaluminophosphates
ASJC Scopus subject areas
- General Materials Science
- Mechanics of Materials
- General Chemistry
- Condensed Matter Physics