摘要 |
Improved operating techniques and apparatus for converting methanol or the like to intermediate olefins and etherification products, such as methyl t-butyl ether, by extracting crude methanol feedstock with an olefinic liquid hydrocarbon stream containing C4+ iso-olefins. The methanol extract phase is reacted under etherification conditions. The aqueous methanol raffinate stream is converted catalytically to olefins for recovery of C4+ olefinic liquid hydrocarbons useful as extraction solvent. A continuous system is provided for converting crude aqueous alcohol feedstock to olefinic hydrocarbons and octane enhancing ethers comprising: extractor means for contacting feedstock liquid containing water with a liquid hydrocarbon extraction stream to provide an extract liquid stream rich in alcohol and an aqueous raffinate stream lean in alcohol; catalytic reactor means for contacting the aqueous alcohol raffinate stream in a catalytic reaction zone with a crystalline acid zeolite catalyst at elevated temperature in an intermediate olefins production zone under process conditions to convert a major portion of alcohol to hydrocarbons; separation means to recover a gaseous stream rich in C3- hyrocarbons and a liquid stream comprising C4+ hydrocarbons; recycle means for contacting at least a portion of the liquid hydrocarbon stream from said separation means with crude alcohol feedstock in said extractor means; and etherification reactor means for contacting at least a portion of extracted alcohol and olefinic liquid hydrocarbon with etherification catalyst to produce an ether product stream.
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