The need to combine different flowrates and partial loading experiments is
particularly true for the small pore zeolites presented in this contribution where it
was shown that different time constants could be extracted using only the results
from experiments at different flowrates. This approach offers also insights in the case
where structural transitions in the materials are triggered by the adsorbing molecule.
When ZLC experiments are properly designed, either as the traditional experiment or as the extended ZLC version, they are an essential tool allowing rapid
feedback to the material experts because both configurations need only very small
sample quantities. The kinetic analysis and the comparison between the different
Rho zeolite samples allowed to guide the research on new synthesis procedures to
progressively improve the material properties in terms of the actual separation
performance. In the case presented, the identification and understanding of the key
role of the cation distribution and how their presence alters the structure were
essential to prepare a second generation of materials which had the correct tradeoff between improved kinetics and size exclusion towards CO 2 capture. This represents a clear example of systematic characterisation of materials followed by a direct
assessment in reference process conditions, which is an essential step for the
development of the next generation of nanoporous adsorbents.
References
1. Abanades JC, Arias B, Lyngfelt A, Mattisson T, Wiley DE, Li H, Ho MT, Mangano E,
Brandani S (2015) Emerging CO 2 capture systems. Int J Greenhouse Gas Control 40:126–166
2. Rajagopalan AK, Rajendran A (2018) The effect of nitrogen adsorption on vacuum swing
adsorption based post-combustion CO 2 capture. Int J Greenhouse Gas Control 78:437–447
3. Kärger J, Ruthven DM, Theodorou DN (2012) Diffusion in nanoporous materials. Wiley-VCH,
Weinheim
4. Eic M, Ruthven DM (1988) A new experimental technique for measurement of intracrystalline
diffusivity. Zeolites 8(1):40–45
5. Hu X, Brandani S, Benin AI, Willis RR (2015) Development of a Semiautomated zero length
column technique for carbon capture applications: rapid capacity ranking of novel adsorbents.
Ind Eng Chem Res 54(16):6772–6780
6. Gibson JAA, Mangano E, Shiko E, Greenaway AG, Gromov AV, Lozinska MM, Friedrich D,
Campbell EEB, Wright PA, Brandani S (2016) Adsorption materials and processes for carbon
capture from gas-fired power plants: AMPGas. Ind Eng Chem Res 55(13):3840–3851
7. Brandani S, Ruthven DM (2002) Analysis of ZLC desorption curves for liquid systems. Chem
Eng Sci 50(13):2055–2059
8. Brandani S (2016) A simple graphical check of consistency for zero length column desorption
curves. Chem Eng Techonol 39(6):1194–1198
9. Brandani S, Ruthven D (1996) Analysis of ZLC desorption curves for gaseous systems.
Adsorption 2(2):133–143
10. Gunadi A, Brandani S (2006) Diffusion of linear paraffins in NaCaA studied by the ZLC
method. Microporous Mesoporous Mater 90(1–3):278–283
11. Brandani S (1998) Effects of nonlinear equilibrium on zero length column experiments. Chem
Eng Sci 53(15):279–2798
12. Brandani S, Jama MA, Ruthven DM (2000) ZLC measurements under non-linear conditions.
Chem Eng Sci 55:1205–1212
Measurement of Diffusion in Small Pore Zeolites to Improve Selectivity in. . .
143
particularly true for the small pore zeolites presented in this contribution where it
was shown that different time constants could be extracted using only the results
from experiments at different flowrates. This approach offers also insights in the case
where structural transitions in the materials are triggered by the adsorbing molecule.
When ZLC experiments are properly designed, either as the traditional experiment or as the extended ZLC version, they are an essential tool allowing rapid
feedback to the material experts because both configurations need only very small
sample quantities. The kinetic analysis and the comparison between the different
Rho zeolite samples allowed to guide the research on new synthesis procedures to
progressively improve the material properties in terms of the actual separation
performance. In the case presented, the identification and understanding of the key
role of the cation distribution and how their presence alters the structure were
essential to prepare a second generation of materials which had the correct tradeoff between improved kinetics and size exclusion towards CO 2 capture. This represents a clear example of systematic characterisation of materials followed by a direct
assessment in reference process conditions, which is an essential step for the
development of the next generation of nanoporous adsorbents.
References
1. Abanades JC, Arias B, Lyngfelt A, Mattisson T, Wiley DE, Li H, Ho MT, Mangano E,
Brandani S (2015) Emerging CO 2 capture systems. Int J Greenhouse Gas Control 40:126–166
2. Rajagopalan AK, Rajendran A (2018) The effect of nitrogen adsorption on vacuum swing
adsorption based post-combustion CO 2 capture. Int J Greenhouse Gas Control 78:437–447
3. Kärger J, Ruthven DM, Theodorou DN (2012) Diffusion in nanoporous materials. Wiley-VCH,
Weinheim
4. Eic M, Ruthven DM (1988) A new experimental technique for measurement of intracrystalline
diffusivity. Zeolites 8(1):40–45
5. Hu X, Brandani S, Benin AI, Willis RR (2015) Development of a Semiautomated zero length
column technique for carbon capture applications: rapid capacity ranking of novel adsorbents.
Ind Eng Chem Res 54(16):6772–6780
6. Gibson JAA, Mangano E, Shiko E, Greenaway AG, Gromov AV, Lozinska MM, Friedrich D,
Campbell EEB, Wright PA, Brandani S (2016) Adsorption materials and processes for carbon
capture from gas-fired power plants: AMPGas. Ind Eng Chem Res 55(13):3840–3851
7. Brandani S, Ruthven DM (2002) Analysis of ZLC desorption curves for liquid systems. Chem
Eng Sci 50(13):2055–2059
8. Brandani S (2016) A simple graphical check of consistency for zero length column desorption
curves. Chem Eng Techonol 39(6):1194–1198
9. Brandani S, Ruthven D (1996) Analysis of ZLC desorption curves for gaseous systems.
Adsorption 2(2):133–143
10. Gunadi A, Brandani S (2006) Diffusion of linear paraffins in NaCaA studied by the ZLC
method. Microporous Mesoporous Mater 90(1–3):278–283
11. Brandani S (1998) Effects of nonlinear equilibrium on zero length column experiments. Chem
Eng Sci 53(15):279–2798
12. Brandani S, Jama MA, Ruthven DM (2000) ZLC measurements under non-linear conditions.
Chem Eng Sci 55:1205–1212
Measurement of Diffusion in Small Pore Zeolites to Improve Selectivity in. . .
143