摘要 |
FIELD: chemistry. ^ SUBSTANCE: invention relates to a method of oligomerising normal butenes, involving: (a) feeding hydrogen and a stream of a mixture of C4, containing dimethyl ether, butadienes, normal butenes and sulphur organic compounds, into a first reactor with a distillation column having a hydrogenation catalyst layer; (b) simultaneously carrying the following in the first reactor with a distillation column: (i) bringing said stream of a mixture of C4 and hydrogen into contact with said hydrogenation catalyst, and thereby carrying out selective hydrogenation of a portion of said butadienes, and (ii) fractionation of the obtained mixture of dimethyl ether and mixture of C4 in the said hydrogenation catalyst layer; (c) removal of a portion said dimethyl ether from said reactor with a distillation column as an overhead product; (d) removal of said mixture of C4 from said reactor with a distillation column as a bottom product, where said bottom product has lower content of dimethyl ether and butadiene; (e) feeding said bottom product into a reactor with a fixed bed containing a chemisorption catalyst which selectively adsorbs sulphur organic compounds, thereby removing a portion of said sulphur organic compounds; and (f) extraction of the stream coming out of said fixed bed reactor as a stream of C4 which contains normal butenes; (g) feeding the outgoing stream into a second reactor with a distillation column having a layer of zeolite catalyst ZSM-57; (h) bringing said normal butenes in said second reactor with a distillation column into contact with said zeolite catalyst ZSM-57 at temperature between 240 and 320 F and pressure between 300 and 400 pounds per square inch, leading the normal butenes into catalytic reaction for form oligomers and, simultaneously, separation and extraction of said oligomers. ^ EFFECT: use of said method increases conversion with high selectivity while working in temperature and pressure conditions less stringent than previously known. ^ 13 cl, 2 ex, 5 tbl, 1 dwg |