Environmental issues alternate fuels

Primary energy supply is a key issue for any new transportation fuel. Constraints on domestic resources and production of petroleum have led to increasing levels of imports. An important policy driver for alternative fuels for transportation in the USA is that they will alleviate some of the issues surrounding dependence and economic vulnerability related to petroleum imports, especially from politically unstable parts of the world. This raises some important questions for hydrogen as a future alternative fuel will the USA have the resources to produce hydrogen for vehicles at low cost and with low environmental impact ... 

Biological, toxicological and environmental issues were also taken into account. Based on these aspects, bioethanol itself does not possess the necessary characteristics as diesel additives, and its conversion into ETBE suffers from limits in the availability of isobutene. There is thus the need to develop alternative oxygenated fuel additives. 

The reader will be referred to much more extensive review articles or books for details on their wide range of appHcations. The annual review issue of the journal Analytical Chemistry is a good starting point. In these review issues, alternating years cover techniques and appHcations. The first are a series of reviews focusing on the variety of analytical techniques, principally the various types of chromatography and spectrometry. The second is divided into a series of articles on areas such as pharmaceuticals, polymer analysis, petroleum and other fossil fuels, and environmental analyses. These issues usually appear as the mid-June volume of the journal. 

When we wrote a previous study (Mather and Wilson, 2006) on the use of textiles in solar electricity conversion, there was a continuing concern about the worldwide dependence on oil as our prime energy source. Alternative fuels each had their promoters and detractors, from both environmental and economic considerations. This outlook has not changed, and the situation may have deteriorated further with political challenges to the assured supply of gas and oil. Therefore, some countries have revisited their shale-based reserves, which are certainly immense but raise issues about environmentally safe extraction. In addition, this fuel would add to atmospheric carbon emissions, which show little sign of being reduced in the near future. 

Branson s initiative, which is both laudable and timely, follows a secular trend where, since the time of the introductirMi of jet aircraft, civil aviation authorities have made inroads into the realm of fuel consumption and made sustained efforts to address the issue of environmental impacts caused by aircraft operations. This is primarily because of the inevitable corollary to the exclusive use of petroleum as industrial fuel. This in turn resulted in the depletion of global oil reserves, where, as far back as 1949 oil was recognized as a finite non renewable resource. Both factors - pollution caused by engine emissions as well as the limits of global oil resources -prompted wide ranging studies on the optimal use of fuel in the aviation industiy and alternative fuel sources. 

The view at Cadmium changed with time starting from a valuable resource and ending up as a toxic element with a limited number of applications not substituted by alternative products. The decontamination of the technosphere works to a certain extent. Due to the character of Cd as trace contamination of phosphate fertilizers and of Zn ores and fossil fuels, there is no final solution for the environmental contamination. Due to the restrictions issued in many countries, there is reason to fear that Cd could end up in unknown material streams. From an analysis of the refining of Zn ores in 2002, it has been concluded that about one quarter of Cd generated as by-product ( 7,000-8,000 Mg) could not be found either in the products analyzed or in the emissions from the process [27]. 

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