Economics biodiesel

Experiments showed that high methyl ester yields can be achieved with solid bases and super acids under moderate reaction conditions. The solid bases were more effective catalysts than the solid super acids. High stability can be achieved by an ordinary inexpensive preparation process, and the catalyst can be separated easily from the reaction products in the heterogeneous catalysis process. The costly catalyst removal process can be avoided compared with the homogeneous process. Therefore, the heterogeneous process using a solid catalyst should be more economical for biodiesel production. 

In conclusion, the economically competitive, non-subsidized production of liquid biofuels requires (a) the use cheaper and more reliable sources of renewable raw material (b) efficient conversion, with minimum waste, of cellulosic, fiber or wood-based, waste biomass into fermentable sugars (c) significantly improved efficiency of the production processes and (d) use by-products (e.g., glycerol in biodiesel production). Several of these aspects are discussed in details in various chapters. 

Biofuels such as biodiesel and bioethanol are, for now, the main alternatives to fossil fuels for the most polluting activities related to transportation. Presently, feedstocks for biofuels production are all of natural origin and as such are subject to uncontrolled seasonal variations. For economic reasons the purchase of these feedstocks from different parts of the world follows the dynamics of commodities markets. ... 

Biodiesel can be produced by a sustainable continuous process based on catalytic reactive distillation. The integrated design ensures the removal of water byproduct that shifts the chemical equilibrium to completion and preserves the catalyst activity. The novel alternative proposed here replaces the liquid catalysts with solid acids, thus dramatically improving the economics of current biodiesel synthesis and reducing the number of downstream steps. The key benefits of this approach are ... 

Although continuous production plants can achieve higher biodiesel throughputs and are less costly to operate per biodiesel unit, batch plants are less expensive to build and can more easily be adapted to changing raw materials and reaction conditions. This flexibility is particularly important given the economic impetus to use diverse TG feedstocks for biodiesel production. Nevertheless, the current trend is toward the construction of continuous production plants given their higher production capacity and lower operational cost, in accordance with current biodiesel demand. 

Even though the base-catalyzed process seems operator friendly and economically possible, it suffers from a key limitation only refined oils and pretreated fats with low concentrations of FFAs be used to produce biodiesel using homogeneous base catalysts. FFAs can react with the base catalyst giving... 

Nowadays, glycerol finds application only for niche markets therefore the co-production of glycerine is becoming a burden for biodiesel producers and a bottleneck limiting the market of this biofuel. The economics of biodiesel depend heavily on using its co-product a high-value use for glycerol could reduce the cost... 

The biorefinery approach is the most sound in terms of truly exploiting the potential of an aquatic biomass, and this concept is now becoming accepted on a worldwide basis. In the biorefinery approach, the economic and energetic value of the biomass is maximized, although it must be emphasized that fluctuations in the prices of fossil carbon (coal, oil, gas) raises uncertainty regarding the opportunity to produce biodiesel from aquatic biomass. For example, when the oil price is below US 120 per barrel it is uneconomic to produce biodiesel in this way. On the other hand, an aquatic biomass demonstrates an excellent potential for use as a source of specialty chemicals, with some components also having added value as animal feeds or fertilizers. 

The production of aquatic biomass focusing initially only on energy production may represent a risky operation, taking into consideration today s large fluctuations in the price of fossil-based oil. As noted above, with fossil-oil prices currently below US 120 per barrel, algal biodiesel is barely competitive with diesel from fossil fuels. However, if the oil price were to exceed US 120 per barrel, then biodiesel from aquatic biomass may become economically viable [21, 22],... 

Biodiesel was prepared in various supercritical alcohol treatments with methanol, ethanol, 1-propanol, 1-butanol, or 1-octanol to study transesterification of rapeseed oil and alkyl esterification of fatty acid at temperatures of 300 and 350°C. The results showed that in transesterification, the reactivity was greatly correlated to the alcohol the longer the alkyl chain of alcohol, the longer the reaction treatment. In alkyl esterification of fatty acids, the conversion did not depend on the alcohol type because they had a similar reactivity. Therefore, the selection of alcohol in biodiesel production should be based on consideration of its performance of properties and economics. 

The U.S. bioethanol industry is growing rapidly. Production in 2007 was 6.5 billion gallons from 139 bioethanol refineries. A further 4 billion gallons of capacity are expected to come online by the end of 2008. In 2006,14% of the corn crop in the United States was used to produce ethanol and probably as a result, com prices increased by 25% in 2007. In the United States 90 plants operated in 2006 and 160 in 2007. Just in Iowa, 42 ethanol and biodiesel plants are in operation and an additional 18 are under construction. A study by the Organization for Economic Cooperation and Development calculated that in order to meet 10% of the fuel requirements of the United States, Canada, and the EU, 30% to 70% of their crop area would have to be devoted to biofuels. 

Economic incentives and private interest in new opportunities are boosting the biofuels market at exceptionally high rates. The European Union gives a strong example. By 2010 the share of alternative fuels should rise to 5.75% by energy value and 6% by volume [14, 15]. Biodiesel is the preferred option in Europe. In contrast, in the USA and Brazil bioethanol is leading, but biodiesel has good... 

Hill, J., Nelson, E., Tilman, D., Polasky, S., and Tiffany, D., Environmental, economic, and energetic costs and benefits of biodiesel and ethanol biofuels, Proc. Natl. Acad. Sci. U.S.A., 103, 11206-11210, 2006. 

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