MFI TİPİ ZEOLİT MEMBRANLARIN YÜKSEK SICAKLIKTA GERİ DÖNGÜLÜ AKIŞ SİSTEMİNDE SENTEZİ

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

SYNTHESIS OF MFI MEMBRANES THROUGH RECIRCULATED FLOW AT ELEVATED TEMPERATURES

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

Keywords:

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

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