Waste isobutanol production from

Synthesis gas, a mixture of mainly CO, CO2, and H2, has been used in chemical industry as feedstock and can be generated by gasification of coal and oil but also from biomass, municipal waste, or by recycling of used plastics (Kopke et al., 2010). Isobutanol production from synthesis gas has so far not been reported. However, Kopke et al. (2010) engineered Clostridium ljungdahlii, which is naturally able to use synthesis gas as carbon and energy source, for the production of 1-butanol by implementation of the CoA-dependent 1-butanol synthesis pathway from Clostridium acetobutylicum. The final titer of about 0.5 mM 1-butanol was rather low however, this approach demonstrated the feasibility to produce fuels and chemicals from synthesis gas. 

The waste products of a home include paper, containers, tin cans, aluminum cans, and food scraps, as well as sewage. The waste products of industry and commerce include paper, wood, and metal scraps, as well as agricultural waste products. Biodegradable wastes, such as paper fines and industrial biosludge, into mixed alcohol fuels (e g., isopropanol, isobutanol, isopentanol). The wastes are first treated with lime to enhance reactivity. Then, they are converted to volatile fatly acids (VFAs) such as acetic acid, propionic acid, and butyric acid, using a mixed culture of microorganisms derived from cattle rumen or anaerobic waste treatment facihties. 

Neopentyl glycol and isobutanol are separated by distillation. Some of the recovered isobutanol is used to extract the aqueous phase formed in the aldol condensation, and the remainder is used to produce synthesis gas. The isobutanol extract contains hydroxypivalaldehyde and starting materials. It is therefore recycled to the aldol condensation reactor. The isobutanol transferred into reactor 1 then enters reactor 2 via the organic phase. This leads to an increase in the amount of isohutanol so that, after separation by distillation, some of the isobutanol can be used to produce synthesis gas. Wastewater from the bottom of the extraction column is fractionated. The low-boiling compounds formed as overhead products are also used to produce synthesis gas (Fig. 25). Wastewater from the fractionating column is treated in the biological waste-water treatment plant. 

Solvents are used in the production of fibers and in their modification and recovery from wastes. Production of fibers with optoelectronic properties for optoelectronic modulators requires several steps. In the first step, a metal hydrate or a hydrated metal compound (based on Pb, La, Zr, Ti) is dispersed in solvent (ethanol, n-propanol, isopropanol, n-butanol, isobutanol, 2-methoxyethanol, or 2-ethoxyethanol), the resulting dispersion is then heated to polymerize the material and stretched to gel the fiber. The final fiber formation is achieved by heating the gelatinized fiber. 

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