Details
| Original language | English |
|---|---|
| Pages (from-to) | 388-394 |
| Number of pages | 7 |
| Journal | Separation and Purification Technology |
| Volume | 72 |
| Issue number | 3 |
| Early online date | 25 Mar 2010 |
| Publication status | Published - 11 May 2010 |
Abstract
ZSM-5 membranes were crystallized on tubular TiO2 supports and evaluated in the permeation of a 50%/50% 1-butene/i-butene mixture. If some of the water in the standard recipe 90 SiO2:0.225 Al2O3:1 Na2O:3.6 TPAOH:1.8 TPABr:1800 H2O was substituted by the same molar amount of short-chain length alcohol, the fluxes and permeances increased remarkably but the 1-butene/i-butene shape selectivity decreased only slightly. This experimental finding is attributed to additional non-zeolite micropores which are formed by the presence of alcohols in the synthesis batch. Since the formation of this additional pore system is linked to a decrease of the crystal size in the membrane layer, the increased length of grain boundaries could represent the structural origin of these additional non-zeolite pores. In a membrane preparation if 25% of the molar amount of water was substituted by ethanol, the 1-butene flux increased by the factor of two, but the mixture separation factor decreased by only 30%. Therefore, relatively thick ZSM-5 layers of about 30 μm gave 1-butene permeances of the order of 1 m3(STP) m-2 h-1 bar-1 with permselectivities of 20 and mixture separation factor of 6. The testing of the ZSM-5 membranes took place under practice-relevant conditions, i.e. with undiluted feeds and without applying sweep gases or reduced pressure on the permeate side.
Keywords
- Alcohol addition, Butene isomer separation, Zeolite membrane engineering, ZSM-5 membranes
ASJC Scopus subject areas
- Chemistry(all)
- Analytical Chemistry
- Chemical Engineering(all)
- Filtration and Separation
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In: Separation and Purification Technology, Vol. 72, No. 3, 11.05.2010, p. 388-394.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - High-flux ZSM-5 membranes with an additional non-zeolite pore system by alcohol addition to the synthesis batch and their evaluation in the 1-butene/i-butene separation
AU - Richter, Hannes
AU - Voß, Hartwig
AU - Voigt, Ingolf
AU - Diefenbacher, Armin
AU - Schuch, Gunter
AU - Steinbach, Frank
AU - Caro, Jürgen
PY - 2010/5/11
Y1 - 2010/5/11
N2 - ZSM-5 membranes were crystallized on tubular TiO2 supports and evaluated in the permeation of a 50%/50% 1-butene/i-butene mixture. If some of the water in the standard recipe 90 SiO2:0.225 Al2O3:1 Na2O:3.6 TPAOH:1.8 TPABr:1800 H2O was substituted by the same molar amount of short-chain length alcohol, the fluxes and permeances increased remarkably but the 1-butene/i-butene shape selectivity decreased only slightly. This experimental finding is attributed to additional non-zeolite micropores which are formed by the presence of alcohols in the synthesis batch. Since the formation of this additional pore system is linked to a decrease of the crystal size in the membrane layer, the increased length of grain boundaries could represent the structural origin of these additional non-zeolite pores. In a membrane preparation if 25% of the molar amount of water was substituted by ethanol, the 1-butene flux increased by the factor of two, but the mixture separation factor decreased by only 30%. Therefore, relatively thick ZSM-5 layers of about 30 μm gave 1-butene permeances of the order of 1 m3(STP) m-2 h-1 bar-1 with permselectivities of 20 and mixture separation factor of 6. The testing of the ZSM-5 membranes took place under practice-relevant conditions, i.e. with undiluted feeds and without applying sweep gases or reduced pressure on the permeate side.
AB - ZSM-5 membranes were crystallized on tubular TiO2 supports and evaluated in the permeation of a 50%/50% 1-butene/i-butene mixture. If some of the water in the standard recipe 90 SiO2:0.225 Al2O3:1 Na2O:3.6 TPAOH:1.8 TPABr:1800 H2O was substituted by the same molar amount of short-chain length alcohol, the fluxes and permeances increased remarkably but the 1-butene/i-butene shape selectivity decreased only slightly. This experimental finding is attributed to additional non-zeolite micropores which are formed by the presence of alcohols in the synthesis batch. Since the formation of this additional pore system is linked to a decrease of the crystal size in the membrane layer, the increased length of grain boundaries could represent the structural origin of these additional non-zeolite pores. In a membrane preparation if 25% of the molar amount of water was substituted by ethanol, the 1-butene flux increased by the factor of two, but the mixture separation factor decreased by only 30%. Therefore, relatively thick ZSM-5 layers of about 30 μm gave 1-butene permeances of the order of 1 m3(STP) m-2 h-1 bar-1 with permselectivities of 20 and mixture separation factor of 6. The testing of the ZSM-5 membranes took place under practice-relevant conditions, i.e. with undiluted feeds and without applying sweep gases or reduced pressure on the permeate side.
KW - Alcohol addition
KW - Butene isomer separation
KW - Zeolite membrane engineering
KW - ZSM-5 membranes
UR - http://www.scopus.com/inward/record.url?scp=77951092942&partnerID=8YFLogxK
U2 - 10.1016/j.seppur.2010.03.011
DO - 10.1016/j.seppur.2010.03.011
M3 - Article
AN - SCOPUS:77951092942
VL - 72
SP - 388
EP - 394
JO - Separation and Purification Technology
JF - Separation and Purification Technology
SN - 1383-5866
IS - 3
ER -