Other Bioalcohols

The alcohols that can be used for motor fuels are methanol (CH3OH), ethanol (C2H5OH), propanol (C3H7OH), and butanol (C4H,OH). However only the first two of the alcohols are technically and economically suitable as fuels for internal combustion engines (ICEs). Main conunercial bioalcohols from renewable feedstocks are bioethanol and biomethanol in the world s energy market. 

Methanol is known as wood alcohol. Generally, methanol is easier to find than ethanol. Sustainable methods of methanol production are currently not economi- 

Before 1920s, methanol was obtained from wood as a co-product of charcoal production, hence the name wood alcohol. Methanol is currently manufactured worldwide from syngas, which is derived from natural gas, refinery off-gas, coal or petroleum, as  

The above reaction can be carried out in the presence of a variety of catalysts including Ni, Cu/Zn, Cu/SiO, Pd/SiO, and Pd/ZnO. In the case of coal, it is first pulverized and cleaned, then fed to a gasifier bed where it is reacted with oxygen and steam to produce the syngas. A 2 1 mole ratio of hydrogen to carbon monoxide is fed to a fixed-catalyst bed reactor for methanol production. Also, the technology for making methanol from natural gas is already in place and in wide use. Ciurent natural gas feedstocks are so inexpensive that even with tax incentives renewable methanol has not been able to compete economically. 

The composition of biosyngas from biomass is shown in Table 3.4. The hydrogen to CO ratio in biosyngas is less than that from coal or natural gas, hence additional hydrogen is needed for full conversion to methanol. The gases produced from biomass can be steam reformed to produce hydrogen and followed by water-gas shift reaction to further enhance the hydrogen content. Wet biomass can be easily 

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Other biofuels with less significant impact and diffusion include biogas, other bioalcohols (eg, biomethanol, biobutanol, etc.), firewood, vegetable oil, bioethers, dried manure, and agricultural waste (Guo et al., 2015). 

Bioethanol is currently the most common biofuel worldwide (Ullah et al., 2014). It has many desirable features as an alternative to petroleum (Akhlaghi et al., 2015) and could help make a smoother transition from petroleum to bio-based industries (Chundawat et al., 2007). Unlike other bioalcohols which are still under investigation, bioethanol has emerged as a potential transportation fuel and has been used as oxygenate to replace MTBE (methyl tertiary butyl ether). Currently, the majority of bioethanol has been generated from food crops (Singh et al., 2014) and it is expected that new-generation biorefinery, which aims to use waste-derived feedstock, can reduce the need for food-crop-based bioethanol in the near future. 

The complete elimination of functional groups is often an undesirable side reaction in organic synthesis, but on the other hand it is a possibility for the recycling of environmentally harmful compounds, for example phenols and haloarenes such as polychlorinated dibenzodioxins (PCDDs or dioxins ). For example, aryl chlorides can be effectively dechlorinated with Pd(0) NPs in tetra-butylammonium salts with almost quantitative conversions also after 19 runs (entry H, Table 1.4) [96]. On the other hand, a C-0 bond cleavage reaction also seems suitable for the fragmentation of sugar-based biomass such as cellulose or cello-biose in that way, sugar monomers and bioalcohol can be derived from renewable resources (entry F, Table 1.4) [164]. 

The bioalchols, such as bioethanol, biobutanol or bioglycerol can be converted to oxygenates fuel additives, acetals. The synthesis of acetal takes place by reacting one of these alcohols with and aldehyde, for example, n-butyraldehyde. Nowadays, aldehydes production takes place through hydroformylation reaction of alkenes, but other process such as bioalcohols oxidation can also be employed to produce aldehydes. Due to the origin of these bioalcohols, the production of the aldehydes by this new process is very attractive, therefore the butanol oxidation to butyraldehyde may be a way more consistent with the current environmental policies. 

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