Methyl tertiary butyl ether alternatives

In the United States, the leading use of alternative fuels is not as standalone fuels, but as additives to petroleum-based gasoline and diesel fuel. For example, gasoline sold m much of the United States is 10 percent ethanol or 10 percent methyl tertiary butyl ether (MTBE). 

Alternative solvents were also tested. Isopropanol and methyl tertiary-butyl ether (MTBE) with water (HCl), the latter a two-phase system, the displayed reaction rates were much slower. 

The introduction of catalytic converters has had a tremendous impact on the composition of gasoline. The catalysts used became poisoned by small amounts of impurities in particular the lead compounds present in high octane gasoline were detrimental. Processes which produce high octane number compounds were therefore stimulated. First, cracking and reforming increased in importance. More recently, the aromatics content is also expected to have to decrease and alternative processes are in use or under way, e.g. the production of MTBE (methyl tertiary-butyl ether). 

Abstract In the last decade, it became increasingly evident that the fuel oxygenate methyl tertiary butyl ether (MTBE) is nearly ubiquitous in the worldwide environment. The detection frequency of MTBE rivals other volatile organic compounds (VOCs) that have been produced and used for a much longer period of time. Its mere presence in water bodies used as drinking water reservoirs (rivers, lakes, or groundwater tables) has aroused concern about its potential sources, persistence, or possible adverse effects (aesthetic or toxic implications) for end-users and aquatic life. The purpose of this chapter is to provide an updated overview of the current environmental concentrations, the occurrence of the pollutant in the different aquatic compartments, the relevance of diffuse and point sources, and the different alternatives for remediation of MTBE contaminated sites. 

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. 

Like propane, n-hutane is mainly obtained from natural gas liquids. It is also a hy-product from different refinery operations. Currently, the major use of n-hutane is to control the vapor pressure of product gasoline. Due to new regulations restricting the vapor pressure of gasolines, this use is expected to he substantially reduced. Surplus n-butane could be isomerized to isobutane, which is currently in high demand for producing isobutene. Isobutene is a precursor for methyl and ethyl tertiary butyl ethers, which are important octane number boosters. Another alternative outlet for surplus n-butane is its oxidation to maleic anhydride. Almost all new maleic anhydride processes are based on butane oxidation. 

Blending and Additives. In the end, all gasoline components are blended together. At a modern refinery, this is done in a computer-controlled process. Additives are used primarily to boost octane rating. Lead was widely used once but was banned in 1996 in the United States, as well as in many other nations. With the increasing prohibition of methyl-tert-butyl-ether (MTBE) in many U.S. states, use of alternatives such as tertiary amyl methyl ether (TAME) or ethyl tert-butyl ether (ETBE) increased. There are many... 

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