MTBE Control

The two fresh fccdstrcams to the column are a pure methanol steam and a C4 stream containing the reactive isobutene and the nonreactive n-butene. The bottoms from the column is mostly MTBE. The distillate is mostly n-butene. 

Reactive Distillation Design and Control. By William L. Luyben and Cheng-Ching Yu Copyright 2008 John Wiley Sons, Inc. 

CONTROL OF MTBE AND ETBE REACTIVE DISTILLATION COLUMNS 

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In the late 1990s, MTBE came under serious attack on grounds of both efficacy and safety. A report by the National Research Council (1999) stated that the addition of oxygen additives in gasoline, including MTBE and ethanol, are far less important in controlling pollution than emission control equipment and technical improvement to vehicle engines and exhaust systems. 

RPLC-PDA is frequently used for quality control, such as the determination of free Irganox 1098 in PA4.6 (at 278 nm after dissolution/precipitation), of free Irganox 1010/1076 in PP (at 278 nm after extraction with MTBE, thus avoiding dissolution of polymer waxes), of Luperco 802 in PP (at 218 nm, after extraction with HCC13), and of Tinuvin 122 in HDPE (at 225 nm as diol). The advantages of the use of HSLC over conventional LC in QC of plastics and additives have been demonstrated, e.g. for AOs in PE, mixed phthalate esters and residual terephthalic acid in PET and partially cured epoxy resins [557],... 

While the above comparison (or similar comparisons for other oxidants) of the amount of oxidant required for different oxidants may hold under controlled laboratory conditions, the actual amount and type of oxidant that is necessary for the treatment of MTBE or other oxygenates at a given site will depend on numerous factors beyond the amount of contaminant present including... 

In general, aboveground treatment systems can be more readily controlled and monitored to optimize the removal of MTBE and other oxygenates than in situ treatment systems. 

A model calculation showed that the HiPOx system may have been fully successful in limiting bromate formation under the chosen oxidant doses if the influent bromide concentration was 0.56 mg/L or less. Since a bromide concentration of 0.56 mg/L is still extremely high for a drinking water source, the HiPOx system appears to hold promise for destroying MTBE and its oxidative by-product TBA while controlling bromate formation, even in waters that have high bromide concentrations.101... 

White, H., Lesnik, B., and Wilson, J.T., Analytical Methods for Oxygenates, LUST Line Bulletin 42, New England Interstate Water Pollution Control Commission, www.epa.gov/oust/MTBE/ LL42Analytical.pdf, October 2002. 

NEIWPCC, A Survey of State Experience with MTBE Contamination at LUST Sites, New England Interstate Water Pollution Control Commission, August 2003. Available at www.neiwpcc.org/ MTBEsum.pdf, 2009. 

Crumbling, D.M. and Lesnik, B., Analytical Issues for MTBE and Related Oxygenate Compounds. L.U.S.T. Line, Bulletin 36, New England Interstate Water Pollution Control Commission, pp. 16-18, 2000. 

Recent developments and concern over the control of fuel exhaust emissions have led to the increased use of combustion system detergents, oxygenates and cetane improvers in fuel. Oxygenated blend components such as ethanol, methyl t-butyl ether (MTBE), ethyl t-butyl ether (ETBE), and /-amylmethyl ether (TAME) are also used to help limit the exhaust emissions from fuel. 

The use of a fuel with a high octane rating is essential in preventing detonation. The quality of the fuel is controlled by the ratio in which different components are blended, and by addition of additives such as methyl tert-butyl ether (MTBE). Although aromatics and olefins increase the octane number, environmental... 

Several pollution control technologies at the refinery promote cross-media transport, the transfer of pollutants from one medium to another. Wastewater, for example, may contain hydrocarbons that volatilize into the air at the refinery, the wastewater treatment plant converted these waterborne hydrocarbons into 2400 tons/year of sludge, which were recycled to the coker. Cross-media transport from air to water is not significant for hydrocarbons or chemical that are only slightly soluble in water (Allen et al, 1989). Studies performed by the National Center for Intermedia Transport at the University of California, Los Angeles, for instance, showed that most hydrocarbons released into the air do not transfer rapidly into other media. Therefore, ignoring intermedia transfer when examining air quality impacts is a reasonable analytical approach. Water-soluble compounds, such as methanol and MTBE, can transfer from air into water and soil media under certain conditions (Cohen et al., 1991). 

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