FUEL 58 |
| Ethylene is an important monomeric raw material for the petrochemical industry. It is used among other things for the production of polyethylene and polyvinyl chloride (PVC) and it is obtained by pyrolysis of naphtha or other fossil based hydrocarbons. Environmental concerns and high petroleum prices have spurred a renewed interest on other sources of ethylene, including ethanol, which can be used as a new raw material for ethylene production. A number of catalytic ethanol dehydration commercial units have been built in the 1950's and 1960's in South America and Asia. These units were based on the passage of ethanol vapor over solid catalysts, such as alumina. Reactors consisted of fixed or fluidized beds. Nevertheless, due to high ethanol prices and the uncertainties related with ethanol price volatility, these dedicated units have been deactivated. However, ethanol can be successfully dehydrated in an FCC unit to produce ethylene, by co-processing with regular FCC feeds, such as Heavy Vacuum Gasoils, and catalysts. Yields are as high as those obtained commercially in dedicated units, of around 95% (stoichiometric), producing an enriched ethylene fuel gas. There are many advantages in this approach: it is not necessary additional investments in the FCC unit and ethanol feeding can be interrupted without any disturbance on FCC operation, if ethanol prices become unattractive. |
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BioFuels: Renewable Liquid Fuels & Chemicals from Biomass
8:05 AM-12:10 PM, Monday, August 20, 2007 Boston Park Plaza -- Arlington Rm, Oral
Division of Fuel Chemistry |