| Summary: | 碩士 === 逢甲大學 === 化學工程學系 === 105 === This study explored the effects of additions of waste syrup (Slurpee) and organic acid (acetic and butyric acid), carbon/nitrogen (C/N) ratio, and iron salt (FeSO4•7H2O) concentration on 1,3-propanediol (PrDOH) production from glycerol with mixed culture using a CSTR (continuous flow stirred tank reactor) reactor. First, the effect of addition of waste syrup was explored and the CSTR reactor was operated at a HRT (hydraulic retention time) of 16 or 24 h under glycerol concentration 60 g/L. The results showed that the addition of syrup had no positive effect on the performance of 1,3-propanediol produced from glycerol. This result resulted from beginning utilization of glycerol after complete utilization of sugar in the reactor. Second, the effect of addition of acetic or butyric acid (0, 2, 4, 8, and 16 g/L) was explored at a glycerol concentration of 60 g/L. The results showed that 1,3-propanediol concentration and yield was about 30 g/L and 0.55 g PrDOH/g glycerol, respectively, when addition of acetic acid was 0-8 g/L. The 1,3-propanediol concentration increased from 28.4 to 32.5 g/L when addition of butyric acid from 0 to 2 g/L; the1,3-propanediol yield and substrate utilization was 0.578 g PrDOH/g glycerol and 93.5%, respectively. When addition of acetic acid was 2-16 g/L or addition butyric acid was 4-8 g/L, the production of acetic acid increased in the effluent. However, only the test of acetic acid addition made the biomass concentration increase. Third, the effect of C/N ratio on 1,3-propanediol was explored. The results showed that the optimal performance of 1,3-propanediol production occurred at a C/N ratio of 32. The 1,3-propanediol concentration, substrate utilization, 1,3-propanediol yield, and 1,3-propanediol production rate was 31.3 g/L, 94.4%, 0.552 g PrDOH/g glycerol, and 1.95 g/L/h, respectively. Final, the effect of iron salt on 1,3-propanediol was explored. The results showed that the advancement of 1,3-propanediol production was not obvious by FeSO4•7H2O from 25 to 50 mg/L when the reactor operated at a glycerol concentration of 60 g/L. However, when the glycerol concentration was 80 g/L, both glycerol utilization and 1,3-propanediol production increased by FeSO4•7H2O from 25 to 50 and 75 mg/L. At FeSO4•7H2O 75 mg/L, the 1,3-propanediol concentration, substrate utilization, 1,3-propanediol yield, and 1,3-propanediol production rate was 42.2 g/L、97.3%、0.543 g PrDOH/g glycerol, and 2.64 g/L/h, respectively.
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