SYNTHESIS OF MFI MEMBRANES THROUGH RECIRCULATED FLOW AT ELEVATED TEMPERATURES

Öz

In this study, MFI type zeolite membranes were synthesised in a recirculating flow system at elevated temperatures. MFI membranes were prepared on the inner surface of the seeded tubular alumina supports in the 140-160oC temperature range. MFI membranes were characterized by scanning electron microscopy, X-ray diffraction and single gas permeation experiments. The best membrane had an-C4H10 single gas permeance of 3.6x10-8 mol/m2-s-Pa and n-C4H10/iso-C4H10ideal selectivity of 20 at 25oC. The results showed that it is possible to produce high quality MFI membranes by a recirculating flow system operating at elevated temperature

Anahtar Kelimeler

• Zeolite membrane, MFI, Recirculated flow system, Gas separation

MFI TİPİ ZEOLİT MEMBRANLARIN YÜKSEK SICAKLIKTA GERİ DÖNGÜLÜ AKIŞ SİSTEMİNDE SENTEZİ

Öz

Bu çalışmada, MFI tipi zeolit membranlar makro gözenekli destekler üzerinde yüksek sıcaklık ve basınç altında geri döngülü akış sisteminde sentezlenmiş ve MFI tipi zeolit membranların özellikleri üzerine membran sentez sıcaklığının etkisi incelenmiştir. Membranların sentezi 140-160oC aralığında iç tarafı nano boyutta MFI tohum kristalleri ile kaplanmış alümina tüpler üzerinde yapılmıştır. Membranlar ve sentez sırasında eş zamanlı olarak oluşan toz malzemeler X-ışını kırınımı, taramalı elektron mikroskobu, ve tanecik boyut dağılımı ölçümleri ile karakterize edilmiştir. Elde edilen membranlarda n-C4H10/isoC ulaşması uygulanan sentez tekniğinin yüksek kalitede membran üretimine olanak sağlayacağını göstermektedir. 10 ile yapılan seçicilik testlerinde ideal seçicilik değerinin 20’ye

Anahtar Kelimeler

• Zeolit membran, MFI, Geri döngülü akış sentezi, Gaz ayrımı

Kaynakça

1. [1] Kresge CT, Dhingra S.S. 2004. Molecular Sieves, Kirk Othmer Encyclopedia of Chemical Technology.
2. [2] Breck D.W. 1974. Zeolite Molecular Sieves: Structure, Chemistry, and Use, New York: Wiley
3. [3] Szostak R. 1984. Handbook of Molecular Sieves, New York: Van Nostrand Reinhold..
4. [4] Funke HH, Kovalchick MG, Falconer JL, Noble RD. 1996. Separation of Hydrocarbon Isomer Vapors with Silicalite Zeolite Membranes, Industrial and Engineering Chemistry Research, Cilt 35, s.1575-1582. DOI: 10.1021/ie950495e
5. [5] Hedlund J, Sterte J, Anthonis M, Bons A, Crastensen B, Corcorand N, Cox D, Deckman H, De Gijnst W, de Moor P, Lai F, McHenry J, Mortier W, Reinoso J, Peters J. 2002. High-flux MFI Membranes, Microporous and Mesoporous Materials, Cilt 52, s.179-189.DOI: 10.1016/S1387-1811(02)00316- 5
6. [6] [6] Noack M, Kölsch P, Schafer R, Toussiant P, Caro J. 2002. Molecular Sieve Membranes for Industrial Application: Problems, Progress, Solutions, Chemical Engineering and Technology, Cilt 25, No 3, s.221-230.
7. [7] [7] Coronas J, Santamaria J. 1999. Separations Using Zeolite Membranes, Separation and Purification Methods, Cilt 28, No 2, s.127-177.DOI: 10.1080/03602549909351646
8. [8] [8] Pina MP, Arruebo M, Felipe M, Fleta F, Bernal MP, Coronas J, Menendez M, Santamaria J. 2004. A Semi-Continuous Method for the Synthesis of NaA Zeolite Membranes on Tubular Supports, Journal of Membrane Science, Cilt 244, s.141-150.DOI: 10.1016/j.memsci.2004.06.049

9. [9] [9] Aguado S, Gascon J, Jansen JC, Kapteijn F. 2009. Continuous Synthesis of NaA Zeolite Membranes, Microporous and Mesoporous Materials, Cilt 120, s.170-176.DOI: 10.1016/j.micromeso.2008.08.06 2
10. [10] [10] Çulfaz PZ, Çulfaz A, Kalıpçılar H. 2006. Preparation of MFI Type Zeolite Membranes in a Flow System with Circulation of the Synthesis Solution. Microporous and Mesoporous Materials, Cilt 92, s.134-144. DOI: 10.1016/j.micromeso.2006.01.00 4
11. [11] [11] Pera-Titus M., Mallada R., Llorens J., Cunill Fidel, Santamaria J. 2006. Preparation of Inner-side Tubular NaA Membranes in a Semi-Continuous Synthesis System, Journal of Membrane Science, Cilt 278, No 1–2, s.401-409. DOI: 10.1016/j.memsci.2005.11.026
12. [12] [12] Richter H, Voight I, Fischer P, Puhlfürβ P. 2003. Preparation of Zeolite Membranes on the Inner Surface of Ceramic Tubes and Capillaries, Separation and Purification Technology, Cilt 32, s.133-138. DOI: 10.1016/S1383- 5866(03)00025-X
13. [13] [13] Dede Ö. 2007. Pervaporation of Organic/Water Mixture by MFI Type Zeolite Membranes Synthesized in a Flow System, Orta Doğu Teknik Üniversitesi, Fen Bilimleri Enstitüsü, Y. Lisans Tezi, Ankara.
14. [14] [14] Topuz B., Önder A., Bowen T., Kalıpçılar H., 2017. Synthesis of ZSM-5 and SAPO-34 Membranes in a High Temperature-Pressure Recirculating Flow System, Chemical Engineering Research and Design, Cilt 117, s.746-755. DOI: 10.1016/j.cherd.2016.11.035
15. [15] Li Y, Zhang X, Wang J, 2001. Preparation for ZSM-5 Membranes by a Two-stage Varying-Temperature Synthesis, Separation and Purification Technology, Cilt 25, s. 459- 466.DOI: 10.1016/S1383- 5866(01)00075-2
16. [16] [16] Hedlund J, Noack M, Kölsch P, Creaser D, Caro J, Sterte J. 1999. ZSM-5 Membranes Synthesized without Organic Templates Using A Seeding Technique, Journal of Membrane Science, Cilt 159, s.263-273. DOI: 10.1016/S0376-7388(99)00069- 1
17. [17] Noack M, Kölsch P, Seefeld V, Toussaint P, Georgi G, Caro J. 2005. Influence of the Si/Al-Ratio on the Permeation Properties of MFI-Membranes, Microporous and Mesoporous Materials, Cilt 79, s.329-337. DOI: 10.1016/j.micromeso.2005.01.00 4
18. [18] Tuan VA, Falconer JL, Noble RD. 1999. Alkali-Free ZSM-5 Membranes:  Preparation Conditions and Separation Performance, Industrial and Engineering Chemistry Research, Cilt 35, s.3635-3646. DOI: 10.1021/ie980808g
19. [19] Au LTY, Yeung KL. 1999. An Investigation of the Relationship Between Microstructure and Permeation Properties of ZSM-5 Membranes, Journal of Membrane Science, Cilt 194, s.33-55. DOI: 10.1016/S0376- 7388(01)00489-6