Sugarcane, bioethanol from

Bioethanol from sugar (sugar heets, sugarcane)... 

It was estimated how much bioethanol can potentially be produced from starch, sugar crops, and agricultural residues. These crops include corn, barley, oat, rice, wheat, sorghum, and sugarcane (12). The potential yield of bioethanol from various biopolymers, i.e., crops is listed in Table 11.1. 

Materials destined for cellulosic ethanol production have been evaluated, and they were found to contain low relative concentrations of fatty acids. Relative to the amount of ethanol produced, the amount of fatty acid byproduct is actually quite significant. Assuming a t q)ical yield of 20% ethanol and 2% fatty acid means that a minimum of 10% of an ethanol producer s high value products could be in the form of fatty acids (59). It has been claimed that microalgal biodiesel is a better alternative than bioethanol from sugarcane (13). 

It has been concluded that microalgal biodiesel is the only renewable biodiesel that has the potential to completely displace liquid transport fuels derived from petroleum. Existing demand for liquid transport fuels could be met sustainably with biodiesel from microalgae, but not with bioethanol from sugarcane (17). 

Physical pre-treatments are essentially processes that reduce the size or disrupt the structure of the biomass substrate in order to increase the surface area. For instance, the milling process is one such example which is also used in the production of bioethanol from sugarcane and corn. 

Currently, bio-PE produced on an industrial scale from bioethanol is derived from sugarcane. Bioethanol is also derived from biorenewable feedstocks, including sugar... 

BNDES, Brazilian Development Bank. Bioethanol from sugarcane—energy for sustainable development. Rio de Janeiro BNDES 2008. 

Cardona, C. A., Quintero, J. A., Paz, 1. C. Production of bioethanol from sugarcane bagasse status and perspectives. Bioresour Technol. 2009,101,4754 766. 

Worldwide, ethanol is mostly produced by fermentation, accoimt-ing for up to 90% of ethanol produced globally. In Brazil, most bioethanol is produced from sugarcane or molasses and in the United States from com. However, other starch materials such as wheat, barley and rye are also suitable as raw material. The starch-containing grains have to be converted into sugar. Thus, in Europe, starch grains, e.g., wheat and sugar beet are the major source of bioethanol production (15). 

In Brazil, the best bioethanol yield from sugarcane is 7.5 m ha (16). However, bioethanol has only 64% of the energy content of biodiesel. This would require planting sugarcane over a very large area, but may be even not available (17). 

Biobased ethylene can be produced from biobased ethanol. The ethanol can be fermented from sugars found in organic sources like corn, sugarcane, potatoes, etc. The two common sources of bioethanol are from corn in the United States or sugarcane in Brazil. Bioethanol is converted to ethene with an aluminum oxide catalyst. The ethene is polymerized to polyethylene. Figure 5.1 lists the molecular formula of ethanol, ethane, and polyethylene. 

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