Renewable resource, ethanol

Liquid fuels play a key role in modem lifestyles. Their liquid nature offers convenience in being transportable and easy to use. Diesel, spark-ignition and Jet engines are the result of this convenience. Unfortunately, the hydrocarbons, which play the major role as liquid fuel are finite, and upon combustion contribute to the accumulation of carbon dioxide in the atmosphere. It is not surprising that alternate renewable liquid fuels are receiving attention. These include ethanol, methanol, fatty acid methyl esters and fast pyrolysis oils. All can be produced from renewable resources. Ethanol may be formed by fermentation of sugars and thereby indirectly from cellulose and starches. Methanol can be produced from carbon monoxide and... 

Because oil and gas ate not renewable resources, at some point in time alternative feedstocks will become attractive however, this point appears to be fat in the future. Of the alternatives, only biomass is a renewable resource (see Fuels frombiomass). The only chemical produced from biomass in commercial quantities at the present time is ethanol by fermentation. The cost of ethanol from biomass is not yet competitive with synthetically produced ethanol from ethylene. Ethanol (qv) can be converted into a number of petrochemical derivatives and could become a significant source. 

Increasingly, biochemical transformations are used to modify renewable resources into useful materials (see Microbial transformations). Fermentation (qv) to ethanol is the oldest of such conversions. Another example is the ceU-free enzyme catalyzed isomerization of glucose to fmctose for use as sweeteners (qv). The enzymatic hydrolysis of cellulose is a biochemical competitor for the acid catalyzed reaction. 

Ethylene. Where ethylene is ia short supply and fermentation ethanol is made economically feasible, such as ia India and Bra2il, ethylene is manufactured by the vapor-phase dehydration of ethanol. The production of ethylene [74-85-1] from ethanol usiag naturally renewable resources is an active and useful alternative to the pyrolysis process based on nonrenewable petroleum. This route may make ethanol a significant raw material source for produciag other chemicals. 

Methanol and ethanol are produced industrially from natural, renewable resources. Go to the web site above, and click on Web Links to find out where to go next. Research the processes that produce these important chemicals. From where do they obtain their raw materials ... 

Interest in renewable resources as raw materials for chemicals and energy has intensified in recent years as a result of anticipated shortages of petroleum and natural gas ( 1, 2, 3). A significant part of this effort has been devoted to the production of alcohols, particularly methanol and ethanol, from wood ( - ) Methanol is the main constituent of "wood alcohol", made for a great many years by the destructive distillation of wood, especially hardwoods W. From a ton of hardwood, one could expect about 60 lb, that is 7.5 gallons of methanol, along with a variety of other chemicals. Wood alcohol is no longer made. The processes discussed in recent reports, are quite different,... 

Clark, D.S., Fowler, D.B., Whyte, R.B. and Wiens, J.K., Ethanol from Renewable Resources. The Canadian Wheat Board,... 

It should be pointed out that the raw materials for VAM and its related polymers (i.e. ethylene and acetic acid) are produced from fossil resources, mainly crude oil. It is possible to completely substitute the feedstock for these raw materials and switch to ethanol, which can be produced from renewable resources like sugar cane, com, or preferably straw and other non-food parts of plants. Having that in mind, the whole production of PVAc, that nowadays is based on traditional fossil resources, could be switched to a renewable, sustainable and C02-neutral production process based on bioethanol, as shown in Fig. 3. If the vinyl acetate circle can be closed by the important steps of biodegradation or hydrolysis and biodegradation of vinyl ester-based polymers back to carbon dioxide, then a tmly sustainable material circle can be established. 

This is the most economical process to produce ethanol, but laws prohibit drinking synthetic ethanol so beverages are made much more expensively by fermentation of sugar or carbohydrates. Recent laws also mandate the addition of 10% ethanol in gasoline in cities during the winter, supposedly to reduce pollution. However, grain processors lobbied to require renewable resources so fermentation is required to produce this fuel alcohol. 

Better established is their use as photocatalysts, in the photoelectro-catalytic production of H2 or the elimination of pollutants, and in developing advanced electrodes for fuel cells, particularly for direct methanol or ethanol oxidation. Nevertheless, also in this case the field can be still considered to be at an earlier stage. It has been shown how several of the results have to be further demonstrated, and issues and limits better defined. However, there are clear indications that this will be a major area of research not only for this specific field, but in general for all catalysis. The recent US DoE report Catalysis for Energy also indicates that the development of better tailored nanostructures for photo- and electro-catalytic applications, particularly for better use of renewable resources, is one of the priority areas of research in catalysis and in general of science. 

Growth of Renewable Resources. There are already large industries, associated with corn processing and food manufacture that utilize enzymes and microbial fermentation on an extremely large scale, In these cases, production and substrate costs can be 70% of the total product costs, and cost efficient engineering becomes paramount. The development of the industry that produces fuel grade ethanol, used as a nonleaded octane... 

In all examples of the palladium-catalyzed telomerization discussed up till now, the nucleophile (telogen) can be considered renewable. The taxogens used (butadiene, isoprene), however, are still obtained from petrochemical resources, although butadiene could, in principle, also be obtained from renewable resources via the Lebedev process that converts (bio)-ethanol into 1,3-butadiene. Limited attention has been given in this respect to the great family of terpenes, as they provide direct access to renewable dienes for telomerization. In particular, those terpenes industrially available, which are derived mostly from turpentine, form an attractive group of substrates. Behr et al. recently used the renewable 1,3-diene myrcene in the telomerization with diethylamine, for instance [18]. The monoterpene myrcene is easily obtained from (3-pinene, sourced from the crude resin of pines, by pyrolysis, and is currently already used in many different applications. 

Many of the existing energy products are being used as fuel for the transport sector and are made from either petrol-based material or from renewable resources such as biomass by some kind of chemical process. The most common biofuels that are being used for transport purposes are dimethyl ether (DME), methanol, ethanol, butanol and biodiesel. 

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