Portal de Periódicos da CAPES

Enhancement of CO 2 Adsorption and CO 2 /N 2 Selectivity on ZIF ‐8 via Postsynthetic Modification

2012; Wiley; Volume: 59; Issue: 6 Linguagem: Inglês

10.1002/aic.13970

1547-5905

Zhijuan Zhang, Shikai Xian, Qibin Xia, Haihui Wang, Zhong Li, Jing Li,

Membrane Separation and Gas Transport

Imidazolate framework ZIF‐8 is modified via postsynthetic method using etheylenediamine to improve its adsorption performance toward CO 2 . Results show that the BET surface area of the modified ZIF‐8 (ED‐ZIF‐8) increases by 39%, and its adsorption capacity of CO 2 per surface area is almost two times of that on ZIF‐8 at 298 K and 25 bar. H 2 O uptake on the ED‐ZIF‐8 become obviously lower compared to the ZIF‐8. The ED‐ZIF‐8 selectivity for CO 2 /N 2 adsorption gets significantly improved, and is up to 23 and 13.9 separately at 0.1 and 0.5 bar, being almost twice of those of the ZIF‐8. The isosteric heat of CO 2 adsorption (Q st ) on the ED‐ZIF‐8 becomes higher, while Q st of N 2 gets slightly lower compared to those on the ZIF‐8 Furthermore, it suggests that the postsynthetic modification of the ZIF‐8 not only improves its adsorption capacity of CO 2 greatly, but also enhances its adsorption selectivity for CO 2 /N 2 /H 2 O significantly. ©2013 American Institute of Chemical Engineers AIChE J, 59: 2195–2206, 2013