Optimal Sugar Compostitions And Conditions For Enhanced Biobutanol Bioproduction From Agriculture Residues

Production of alternative non-fossil biofuels based on renewable resources has been the focus of research in the past few decades due to its environmental and economical advantages. The current study focuses on testing two Clostridia strains towards production of butanol. The work was performed in three parts: the first part includes introducing C acetobutylicum ATCC 4259 for butanol production and identifying the proper working conditions for this strain. The following part includes extending investigation of production to examine C. beijerinckiiBA101 and compare with results obtained from C. acetobutylicum. In the last part, an optimization study was conducted on a presently derived mathematical model in order to predict the best sugar composition in the feedstock for maximum production of butanol. Results showed that the agriculture residues are potential biomass resource for biofuel industry sin both Clostridia strains were successfully able to utilize all types of agricultural sugars including hexose and pentose. However, using C. beijerinkckii resulted in 53% higher butanol concentration than using introduced C. acetobutylicum. The yield was fairly comparable, while high acid accumulation found when using C. acetobutylicum made this strain inapplicable to anaerobic batch fermentation without effective system of pH control.

Optimal Sugar Compostitions And Conditions For Enhanced Biobutanol Bioproduction From Agriculture Residues

Production of alternative non-fossil biofuels based on renewable resources has been the focus of research in the past few decades due to its environmental and economical advantages. The current study focuses on testing two Clostridia strains towards production of butanol. The work was performed in three parts: the first part includes introducing C acetobutylicum ATCC 4259 for butanol production and identifying the proper working conditions for this strain. The following part includes extending investigation of production to examine C. beijerinckiiBA101 and compare with results obtained from C. acetobutylicum. In the last part, an optimization study was conducted on a presently derived mathematical model in order to predict the best sugar composition in the feedstock for maximum production of butanol. Results showed that the agriculture residues are potential biomass resource for biofuel industry sin both Clostridia strains were successfully able to utilize all types of agricultural sugars including hexose and pentose. However, using C. beijerinkckii resulted in 53% higher butanol concentration than using introduced C. acetobutylicum. The yield was fairly comparable, while high acid accumulation found when using C. acetobutylicum made this strain inapplicable to anaerobic batch fermentation without effective system of pH control.

A Novel Approach for Measurement of Composition and Temperature of N-Decane/Butanol Blends Using Two-Color Laser-Induced Fluorescence of Nile Red

In this work, the possibility of using a two-color LIF (laser-induced fluorescence) approach for fuel composition and temperature measurements using nile red dissolved in n-decane/butanol blends is investigated. The studies were conducted in a specially designed micro cell enabling the detection of the spectral LIF intensities over a wide range of temperatures (283–423 K) and butanol concentrations (0–100 vol.%) in mixtures with n-decane. Furthermore, absorption spectra were analyzed for these fuel mixtures. At constant temperature, the absorption and LIF signals exhibit a large spectral shift toward higher wavelengths with increasing butanol concentration. Based on this fact, a two-color detection approach is proposed that enables the determination of the butanol concentration. This is reasonable when temperature changes and evaporation effects accompanied with dye enrichment can be neglected. For n-decane, no spectral shift and broadening of the spectrum are observed for various temperatures. However, for butanol admixture, two-color thermometry is possible as long as the dye and butanol concentrations are kept constant. For example, the LIF spectrum shows a distinct broadening for B20 (i.e., 80 vol.% n-decane, 20 vol.% butanol) and a shift of the peak toward lower wavelengths of about 40 nm for temperature variations of 140 K.

Biobutanol Production Using High Cell Density Fermentation in a Large Extractant Volume

Biobutanol is well-known as a suitable substitute for gasoline which can be applied without enginemodification. Butanol toxicity to the producer strain causes difficulties to grow strain with more than 4 g/L dry cellweight and to produce butanol more than 20 g/L. Fermentation with high initial cell density was reported to enhancebutanol productivity. In addition, oleyl alcohol has been recognized to perform effective extraction for butanol because ofits selectivity and biocompatibility so that reducing toxicity effect. Butanol fermentation with high cell density and largeextractant volume has not been reported and is expected to improve butanol production in minimum medium volume.Clostridium saccharoperbutylacetonicum N1-4, C. beijerinckii NCIMB 8052 (8052), and C. acetobutylicum ATCC 824(824) were used in this study. Three kinds of media, TYA, TY, and TY-CaCO3, were used to investigate in conventionalextractive fermentation. Then, in situ extractive fermentations with Ve/Vb ratios at 0.1, 0.5, 1.0, and 10 were operated.Total butanol concentration was defined as the broth based total butanol, that is total amounts of butanol produced inbroth and extractant per the volume of broth. TYA medium resulted the highest total butanol concentrations by N1-4 (12g/L), 8052 (11 g/L), and 824 (15 g/L) and the highest partition coefficient (3.7) among the three media with Ve/Vb ratiosat 0.5. N1-4 yielded the highest increment of total butanol production (22 g/L) in the extractive fermentation with highcell density. Low butanol concentration of 0.8 g/L butanol in broth was maintained with the extractant to broth volumeratio (Ve/Vb), which was much lower than 4.4 g/L with the ratio of 0.5. Ve/Vb ratio of 10 provided 2-fold higher totalbutanol concentration (28 g/L) than that 11 g/L obtained with Ve/Vb ratio of 0.5. These results indicated that largervolume of extractant to broth improved total butanol concentration by reducing butanol toxicity and led to high mediumbasedbutanol yield in fermentation using high cell density.

Molecular dynamics simulation on the interfacial features of supercritical 1-butene/subcritical water

We studied the interfacial features of 1-butene/water and extraction process of 2-butanol by molecular dynamics (MD) simulations. The infinite dilute diffusion coefficients of 1-butene in water is larger than that of 2-butanol, and one important reason is that 2-butanol molecules can form hydrogen bonds with water molecules. 1-butene is more soluble in water under supercritical condition than that under subcritical condition. 1-butene under supercritical condition can extract more 2-butanol from aqueous solution than that under other conditions. A process of producing 2-butanol by the direct hydration of 1-butene is more competive when it operates under the supercritical conditions of 1-butene which due to a higher solubility of 1-butene in water, a larger diffusion coefficient of 1-butene and a lower 2-butanol concentration in water.