Struct Bond (2020) 184: 85–120
https://doi.org/10.1007/430_2020_68
# Springer Nature Switzerland AG 2020
Published online: 26 September 2020
Efficient Downstream Processing
of Renewable Alcohols Using Zeolite
Adsorbents
Benjamin Claessens, Julien Cousin-Saint-Remi, and Joeri F. M. Denayer
Contents
1 The Production of Renewable Alcohols in a Biorefinery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
2 MFI Zeolites: ZSM-5 and Silicalite-1 . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
2.1 Structure and Selectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
2.2 Which Channel to Choose? The Adsorption Mechanism of Alcohols on MFI
Zeolites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
2.3 The Adsorption of Water: Si/Al Ratio, Cations, Defects, and Co-adsorption . . . . . . . 94
2.4 Diffusion of Alcohols and Water in MFI Frameworks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
2.5 Process Aspects and Mixture Separation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
3 Cage-and-Window-Type Zeolites: LTA and CHA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
3.1 Framework Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
3.2 Equilibrium: Chain-Length and Entropic Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
3.3 Kinetics: Co-diffusion and Crystal Diversity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
3.4 Separation of ABE Mixtures on ITQ-29 and CHA Zeolites . . . . . . . . . . . . . . . . . . . . . . . . . 105
3.5 Combining the Selectivity of CHA and LTA Zeolites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
4 Conclusions and Future Perspectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Abstract Increasing energy prices, global warming, and concerns for environmental pollution has been pushing the chemical industry to look for alternatives for
traditional, fossil-based chemical feedstocks. Important platform molecules are
alcohols, which can be produced from renewable feedstocks via fermentation. The
implementation of these fermentation processes to produce chemicals leads to
important challenges regarding the downstream purification. Adsorption-based purification technologies are alternatives for traditional energy-intensive distillation
processes. The well-defined pore structure of zeolites makes them ideal candidates
for the removal of alcohols from these complex fermentation mixtures, which
contain cells and cell debris, acids, sugars, lipids, and proteins. The following
B. Claessens, J. Cousin-Saint-Remi, and J. F. M. Denayer (*)
Vrije Universiteit Brussel, Brussels, Belgium
e-mail: Joeri.Denayer@vub.be
https://doi.org/10.1007/430_2020_68
# Springer Nature Switzerland AG 2020
Published online: 26 September 2020
Efficient Downstream Processing
of Renewable Alcohols Using Zeolite
Adsorbents
Benjamin Claessens, Julien Cousin-Saint-Remi, and Joeri F. M. Denayer
Contents
1 The Production of Renewable Alcohols in a Biorefinery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
2 MFI Zeolites: ZSM-5 and Silicalite-1 . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
2.1 Structure and Selectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
2.2 Which Channel to Choose? The Adsorption Mechanism of Alcohols on MFI
Zeolites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
2.3 The Adsorption of Water: Si/Al Ratio, Cations, Defects, and Co-adsorption . . . . . . . 94
2.4 Diffusion of Alcohols and Water in MFI Frameworks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
2.5 Process Aspects and Mixture Separation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
3 Cage-and-Window-Type Zeolites: LTA and CHA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
3.1 Framework Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
3.2 Equilibrium: Chain-Length and Entropic Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
3.3 Kinetics: Co-diffusion and Crystal Diversity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
3.4 Separation of ABE Mixtures on ITQ-29 and CHA Zeolites . . . . . . . . . . . . . . . . . . . . . . . . . 105
3.5 Combining the Selectivity of CHA and LTA Zeolites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
4 Conclusions and Future Perspectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Abstract Increasing energy prices, global warming, and concerns for environmental pollution has been pushing the chemical industry to look for alternatives for
traditional, fossil-based chemical feedstocks. Important platform molecules are
alcohols, which can be produced from renewable feedstocks via fermentation. The
implementation of these fermentation processes to produce chemicals leads to
important challenges regarding the downstream purification. Adsorption-based purification technologies are alternatives for traditional energy-intensive distillation
processes. The well-defined pore structure of zeolites makes them ideal candidates
for the removal of alcohols from these complex fermentation mixtures, which
contain cells and cell debris, acids, sugars, lipids, and proteins. The following
B. Claessens, J. Cousin-Saint-Remi, and J. F. M. Denayer (*)
Vrije Universiteit Brussel, Brussels, Belgium
e-mail: Joeri.Denayer@vub.be