FARKLI HİDROLİK ALIKONMA SÜRELERİNDE KEÇİBOYNUZU EKSTRAKTI BESİYERİNDE SÜREKLİ ETANOL FERMANTASYONU

Öz

Enerji endüstrisinin tüm dünyada ucuz yenilenebilir kaynaklar sağlaması için önemli biyoproseslerden birisi biyoetanol üretimidir. Bu çalışmada serbest veya immobilize edilmiş S. cerevisiae hücreleri ile ucuz bir karbon kaynağı olan keçiboynuzu ekstraktından sürekli etanol fermantasyonları amaçlanmıştır. Sürekli etanol fermantasyonları farklı hidrolik alıkonma sürelerinde (4-20 saat) gerçekleştirilmiştir. Optimum hidrolik alıkonma süreleri, serbest haldeki hücreler için 8 sa ve immobilize edilmiş hücreler için 6.67 sa olarak belirlenmiştir. Serbest ve immobilize hücre fermantasyonları için en yüksek etanol üretim oranları sırasıyla 3.12 g/L/sa ve 3.37 g/L/sa olarak hidrolik alıkonma süresi 5.71 saatte elde edilmiştir. Tüm kinetik parametreler, her iki hücre tipinin etanol fermantasyonu için kullanılabileceğini ve immobilize edilmiş S. cerevisiae hücreleri ile gerçekleştirilen etanol fermantasyonunun, süspansiyon haldeki hücrelere kıyasla biyokütleden bağımsız olarak daha yüksek seyreltme oranlarında gerçekleştirilebileceğini açıkça göstermiştir.

Anahtar Kelimeler

• Sürekli fermantasyon,serbest ve immobilize hücreler,karıştırmalı tank tipi biyoreaktör

CONTINUOUS ETHANOL FERMENTATION FROM CAROB POD EXTRACT MEDIUM AT DIFFERENT HYDRAULIC RESIDENCE TIME (HRT)

Öz

Production of bioethanol is one of the important bioprocesses for the energy industry to provide inexpensive renewable resources all over the world. In this context, this research was organized for continuous ethanol fermentation from carob pod extract which is an inexpensive carbon source by free or immobilized S. cerevisiae cells. Continuous ethanol fermentations were performed with different HRT (from 4 to 20 h) and optimal HRT were 8 h for the free cell, and 6.67 h for immobilized cell, respectively. The highest volumetric ethanol productivities for free cell and immobilized cell fermentations were 3.12 g/L/h and 3.37 g/L/h at HRT of 5.71 h, respectively. All kinetic parameters clearly showed that both cell types can be used for ethanol fermentation, and immobilized S. cerevisiae ethanol fermentation can be operated at higher dilution rates independent of biomass than a free cell.

Anahtar Kelimeler

• Continuous fermentation,stirred tank bioreactor,free and immobilized cells,stirred tank bioreactor

Kaynakça

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