Zeolite membrane technology in biomass to motor fuel processes

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Zeolite membrane technology in biomass to motor
fuel processes

• Jonas Hedlund
• Division of Chemical Engineering
• Luleå University of Technology (LUT)

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What is zeolite?

• General
• Aluminosilicate mineral
• Stable at high temperatures (several hundred C)
• Channels with diameters of 0.3-1.3 nm exactly
  determined by the structure
• Over 176 different zeolites are known
• Occur in nature as minerals and can also be
  prepared synthetically
• Good adsorbents, ion-exchangers and catalysts

The MFI structure
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Zeolite minerals

• Photograph of about 2 billion years old Natrolite
  (left) and Stilbite (right) from Faroe
• Islands and Sweden.

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Major current applications for zeolites in the
form of powders or pellets

• Adsorbents

Detergent powder
Catalysts
Zeolite beads (d4 mm) for drying of gas
and liquids
Zeolite A crystals act as softeners (by
ion- exchange) in detergent
Extruded zeolite acid catalyst. Zeolites can
be used for catalytic cracking to
produce gasoline, DME synthesis and gasoline
synthesis.
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Zeolite films open up for new applications
25 mm
Zeolite membrane prepared at LUT
Zeolite films on stainless steel The photograph
shows FAU films on stainless steel prepared at
LUT. The film thickness varies between
the samples, resulting in varying interference
colors.

• New applications for zeolite films
• Sensors
• Membranes
• Structured catalysts
• Structured adsorbents

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Zeolite membranes

• Advantages
• Can be used at high temperature and pressure,
  unlike polymeric membranes
• Potentially highly selective

• Separation mechanisms in
• zeolite membranes
• Sieving
• Adsorption
• Diffusion

Continuous operation
Separation factor ?

• Throughput
• Permeance mol/(m2 s Pa)
• Flux kg/(m2 s)

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Pervaporation is useful for bio-fuel production
First commercial application Ethanol
dehydration using a polar zeolite A membrane in
order to arrive at the final fuel with low water
content.
Numerous other separations using pervaporation
and zeolite membranes Bowen et al., Fundamentals
and applications of pervaporation through zeolite
membranes. Journal of membrane science, 2004.
245 1-33.
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Performance for a commercial 40 mm zeolite A
membrane compared to polymeric membranes for
separation of water/ethanol by pervaporation
Morigami et al. Separation and Purification
Technology, (2001) 25 251-260.
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First large scale pervaporation unit designed by
Mitsui Engineering and Shipbuilding (MES) in 2001
Dehydration of Ethanol
Morigami et al. Separation and Purification
Technology, (2001) 25 251-260.
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Latest pervaporation news
MES July 30 2007, ST1 Biofuels Oy, orders unit
for dehydration of 35,000 tons/year bio-ethanol
from MES. The bio-ethanol is produced from
food waste. The module has 8 membrane units, each
of which has 50 m2 area and is composed of 1,700
zeolite membrane pipes with length of 800 mm
and outer diameter of 12 mm. Cost 9 000 000
SEK.
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The thinnest (500 nm) zeolite membranes are
prepared at LUT
Hedlund et al. Microporous and Mesoporous Mater.
52 (2002) 179.
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Gas separation performance of membranes prepared
at LUT
Hedlund et al. Microporous and Mesoporous Mater.
52 (2002) 179.
p-Xylene flux 1.3 kg/(m2 h), at ?pp-xy1.25
bar, sufficient for commercial applications
Pervaporation performance will be evaluated soon
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Applications of zeolite membranes in order to
improve processes for bio-fuel production from
synthesis gas
Schematic block diagram illustrating production
of renewable fuels or electrical power from
biomass. Potential applications of zeolite
membranes at process conditions in order to
improve the processes are indicated in yellow.
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Very promising results for separation of CO2 from
synthesis gas at atmospheric pressure
CO2 flux 24 kg /(m2 h) at ?pCO21 bar!
Next step High pressure tests
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Very promising results for separation of methanol
from synthesis gas at atmospheric pressure
Methanol flux 14 kg /(m2 h) at ?pMethanol1 bar!
Next step High pressure tests
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Acknowledgements

• Financial support from
• Swedish Energy Agency
• Selective membranes for efficient hydrogen
  production by steam reforming
• (PhD student Jonas Lindmark)
• Catalytic synthesis of methanol/DME via black
  liqour gasification
• (PhD student Caroline Häggström)
• Swedish Science Council
• Separation of CO2, methanol or ethanol in gas
  phase by zeolite membranes
• (PhD student Linda Stenberg)

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That was all!Thanks for your attention!Questio
ns?