Carbon dioxide capture from industrial flue gas surrogate by multi-cyclical PSA mediated by microporous palm kernel shell and ZIF-8 media

This study explores the application of microporous APKS and ZIF-8 adsorbents for carbon dioxide capture from flue gas surrogate. The purity and recovery of N2 and CO2 in the product and waste stream were simulated and experimented in the lab. The experimental breakthrough at different N2/CO2 stream adsorption compositions validated the Aspen adsorption model. Results from the simulation show that in the product stream, factors such as adsorbent type (APKS), lower adsorption times, and low CO2 concentration in the feed led to improved N2 purity. On the other hand, results from the experiment show that the CO2 feed compositions, type of adsorbent and cyclical pressure swing operation correlated significantly with the purity and recovery of the CO2 in the waste stream. Interestingly, as previously understood, the high surface area was important but not a guarantee to achieve the highest product purity. The highest CO2 purity of 83% was obtained using APKS. In contrast, the highest CO2 recovery of 65% was obtained by ZIF-8. The degraded performance at the increasing cycle was due to the inability of both porous media to regenerate completely, causing product contamination and blockages of the CO2 affinitive sites of the adsorbents from capturing the gas effectively.