Binderless SAPO-34 beads for selective CO2 adsorption

Abstract

Selective adsorption of CO2 from biogas allows isolating biomethane, which can then be used as a direct substitute for natural gas. The microporous zeotype SAPO-34 is a suitable material for CO2 adsorption because it can achieve high working capacity at relatively mild regeneration conditions. In industrial applications, adsorbents need to be shaped into a macroscopic format (e.g. beads, pellets) in order to reduce the pressure drop over the adsorption column. Typically, an inert binder is added to the powder to achieve the desired format. In this work, novel hierarchically porous binderless SAPO-34 beads with a diameter in the range 0.7–1.2 mm were synthesised employing an ion-exchange resin as a hard template. The interior of the beads consisted mostly of small SAPO-34 crystals ( 1 bar.

Keywords

• CO2 adsorption
• Silicoaluminophosphate (SAPO)
• Biogas upgrading
• hierarchical porosity
• working capacity