Aluminophosphates for CO2 Separation
2011 (English)In: CHEMSUSCHEM, ISSN 1864-5631, Vol. 4, 91-97 p.Article in journal (Refereed) Published
The pressure-swing adsorption method for carbon dioxide capture would ideally be facilitated by adsorbents with a high capacity and a high selectivity for CO(2). Several aluminophosphates with 8-ring window apertures (AlPO(4)-17, AlPO(4)-18, AlPO(4)-53, and AlPO(4)-25) were synthesized by hydrothermal crystallization, calcined, and their CO(2) uptake and CO(2)/N(2) selectivity were studied. CO(2) and N(2) uptake was determined for pressures up to 101 kPa at 273 and 293 K. Langmuir and Toth adsorption models were used to describe the adsorption isotherms. The CO(2) and N(2) uptakes strongly indicated that the squeezed 8-ring windows of certain aluminophosphates can sieve CO(2) from a CO(2) and N(2) gas mixture. Both AlPO(4)-53 and AlPO(4)-25 exhibited a remarkably higher uptake of CO(2) compared to N(2). The hydrophilicity of the AlPO(4) materials was investigated by means of water adsorption, and the results showed that all of the tested aluminophosphates were less water sensitive than a benchmark zeolite (13X). In particular, AlPO(4)-53 and AlPO(4)-25 showed a very low degree of water uptake with up to 20-30% relative humidity. Determination of cyclic adsorption and desorption confirmed the relatively hydrophobic nature of the aluminophosphates, which render them less energy costly for the regeneration of adsorbents.
Place, publisher, year, edition, pages
Wiley-Blackwell, 2011. Vol. 4, 91-97 p.
IdentifiersURN: urn:nbn:se:su:diva-68149DOI: 10.1002/cssc.201000256ISI: 000287138900015OAI: oai:DiVA.org:su-68149DiVA: diva2:471911
authorCount :42012-01-032012-01-032014-04-02Bibliographically approved