FIELD: chemistry.
SUBSTANCE: invention relates to a process for the recycling naphthenes to a reactor, as well as to a device. Method comprises: reacting in a reactor a reactor feed stream containing xylene isomers, ethylbenzene, C8-naphthenes and hydrogen, on an ethylbenzene isomerisation catalyst under reactor conditions, wherein at least a portion of the ethylbenzene in the reactor feed stream is converted to xylene isomers so that a reactor effluent containing xylene isomers and C8-naphthenes is formed; cooling and separating the reactor effluent to form a first condensed liquid stream and a first vapour stream; cooling and separating the first vapour stream to form a second condensed liquid stream and a second vapour stream; feeding the first condensed liquid stream and the second condensed liquid stream to a side-draw tower to obtain a side stream comprising C8 aromatics and C8-naphthenes; extracting para-xylene from the side stream in the para-xylene extraction section to obtain a para-xylene depleted stream, wherein the para-xylene depleted stream contains a portion of the C8-naphthenes; and recycling the depleted para-xylene stream to the reactor. Para-xylene depleted stream is recycled back to the reactor, thereby preventing excessive loss of naphthenes from the processes.
EFFECT: energy-saving recycling of naphthenes is proposed through the use of a side-draw fractionating tower and partial condensation.
18 cl, 4 dwg, 7 tbl, 2 ex
