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.