Verfahren zur Fraktionierung von vorwiegend C8 aromatischen Kohlenwasserstoffgemischen

摘要

1311606 Separating C 8 aromatic hydrocarbons FLUOR CORP 19 April 1971 [23 March 1970] 22780/71 Addition to 1277457 Heading C5E Feedstocks comprising xylenes and ethylbenzene are separated into components by a process comprising: (a) pre-fractionating the feed and/or chemically depleting the feed of m-xylene to form a first C 8 aromatic feed stream relatively rich in ethylbenzene; (b) feeding this first stream into a multilevel fractionation zone into an intermediate tray ; (c) feeding a second C 8 aromatic stream relatively rich in o-xylene to a tray below the first feed tray; (d) separating an ethylbenzene overhead stream, a predeominantly o-xylene bottom stream and a xylene isomer sidestream from between the first and second feed trays. The xylene sidestream may be treated to remove p-xylene, passed to a conversion zone to isomerize m-xylene to other xylene isomers and returning the isomerization products to the fractionation zone as the second feed stream. The initial feedstock may be prefractionated to give an overhead stream for use as the first feed stream, and a bottom stream for use as the second feed stream.