pH 제어식 미생물 반응조를 이용한 합성가스 발효에 의한 바이오에탄올 생산성 검토 = Ethanol Production of Syngas Fermentation in a pH-Controlling Bioreactor using Clostridium ljungdahlii

다국어 초록 (Multilingual Abstract)

Clostridium ljungdahlii is a bacterium can transform synthesis gas or mixture of carbon monoxide and hydrogen to ethanol and acetate acid according anaerobic processes. Many researches have been conducted about medium optimum conditions, genes researches and effects of syngas composition and pressure on cell population and ethanol production. Especially it was found that pH is very important for cell growth and ethanol production. This study was to research effect of pH range on cell growth and ethanol production. A series of experiments were conducted under strictly anaerobic conditions with pH at 7.0, 6.0 and 5.4 to 5.9 in a pH-controlling bioreactor. It was observed that ethanol production started from pH reducing and acetate acid appearance. Cell concentration increased fast when pH between 5.6 and 5.9. It was presented that the maximum cell concentration was reached to 0.498g/L in 60 hours when pH to 5.6. The ethanol production was 1.056g/L at the same time. In a typically cell growing process, cell growing occurred in optimum growth pH 5.0 to 7.0, carbon source such as syngas and fructose was transferred to cell, ethanol and acetic acid or other organic acid in this process.