Provided is a method for producing a propylene oligomer, which is advantageous in that a lowly branched propylene oligomer can be obtained at high selectivity. A method for producing a propylene oligomer, including an oligomerization step of oligomerizing propylene at lower than 160° C. in the presence of at least one member selected from a group consisting of a catalyst containing crystalline molecular sieve and a catalyst containing phosphoric acid, a fractional distillation step of obtaining a fraction containing a propylene trimer, a propylene tetramer, or a mixture thereof, and an isomerization step of isomerizing the propylene trimer, propylene tetramer, or mixture thereof contained in the fraction in the presence of a catalyst containing phosphoric acid.

Provided is a method for producing a propylene oligomer, which is advantageous in that a lowly branched propylene oligomer can be obtained at high selectivity. A method for producing a propylene oligomer, including an oligomerization step of oligomerizing propylene at lower than 160° C. in the presence of at least one member selected from a group consisting of a catalyst containing crystalline molecular sieve and a catalyst containing phosphoric acid, a fractional distillation step of obtaining a fraction containing a propylene trimer, a propylene tetramer, or a mixture thereof, and an isomerization step of isomerizing the propylene trimer, propylene tetramer, or mixture thereof contained in the fraction in the presence of a catalyst containing phosphoric acid.

Provided is a method for producing a propylene oligomer, which is advantageous in that a lowly branched propylene oligomer can be obtained at high selectivity. A method for producing a propylene oligomer, including an oligomerization step of oligomerizing propylene at lower than 160° C. in the presence of at least one member selected from a group consisting of a catalyst containing crystalline molecular sieve and a catalyst containing phosphoric acid, a fractional distillation step of obtaining a fraction containing a propylene trimer, a propylene tetramer, or a mixture thereof, and an isomerization step of isomerizing the propylene trimer, propylene tetramer, or mixture thereof contained in the fraction in the presence of a catalyst containing phosphoric acid.

Processes and apparatuses for the production of propylene are provided. In an embodiment, a process is provided for production of propylene from an oxygenate feed comprising passing the oxygenate feed to an oxygenate-to-olefin reactor to contact the oxygenate feed with a catalyst to provide an effluent stream comprising olefins comprising ethylene, propylene and butylene. The effluent stream is separated in a product separation zone to generate a propylene product stream, an ethylene stream and a C.sub.4+ stream. The ethylene stream is reacted in an ethylene dimerization or oligomerization reactor in presence of a dimerization or oligomerization catalyst to provide a first process stream. The C.sub.4+ stream and the first process stream are cracked in a cracking reactor under cracking conditions to provide a cracked stream comprising additional amounts of ethylene and propylene. Finally, the cracked stream is passed to the product separation zone to recover additional amounts of propylene.

Processes and apparatuses for the production of propylene are provided. In an embodiment, a process is provided for production of propylene from an oxygenate feed comprising passing the oxygenate feed to an oxygenate-to-olefin reactor to contact the oxygenate feed with a catalyst to provide an effluent stream comprising olefins comprising ethylene, propylene and butylene. The effluent stream is separated in a product separation zone to generate a propylene product stream, an ethylene stream and a C.sub.4+ stream. The ethylene stream is reacted in an ethylene dimerization or oligomerization reactor in presence of a dimerization or oligomerization catalyst to provide a first process stream. The C.sub.4+ stream and the first process stream are cracked in a cracking reactor under cracking conditions to provide a cracked stream comprising additional amounts of ethylene and propylene. Finally, the cracked stream is passed to the product separation zone to recover additional amounts of propylene.

Processes and apparatuses for the production of propylene are provided. In an embodiment, a process is provided for production of propylene from an oxygenate feed comprising passing the oxygenate feed to an oxygenate-to-olefin reactor to contact the oxygenate feed with a catalyst to provide an effluent stream comprising olefins comprising ethylene, propylene and butylene. The effluent stream is separated in a product separation zone to generate a propylene product stream, an ethylene stream and a C.sub.4+ stream. The ethylene stream is reacted in an ethylene dimerization or oligomerization reactor in presence of a dimerization or oligomerization catalyst to provide a first process stream. The C.sub.4+ stream and the first process stream are cracked in a cracking reactor under cracking conditions to provide a cracked stream comprising additional amounts of ethylene and propylene. Finally, the cracked stream is passed to the product separation zone to recover additional amounts of propylene.

In a feed clean-up process at least two adsorbents (2, 4) are installed in front of an oligomerization reactor (3). Olefin feed is sent over one adsorbent (2) and the nitrile poisons are adsorbed so that clean feed will enter the reactor (3). Before the adsorbent (2) will be saturated, the feed (1) is sent to the other, fresh adsorbent (4). At the same time oligomerization product from the reactor (3) is used to desorb nitriles from the spent adsorbent (2).

In a feed clean-up process at least two adsorbents (2, 4) are installed in front of an oligomerization reactor (3). Olefin feed is sent over one adsorbent (2) and the nitrile poisons are adsorbed so that clean feed will enter the reactor (3). Before the adsorbent (2) will be saturated, the feed (1) is sent to the other, fresh adsorbent (4). At the same time oligomerization product from the reactor (3) is used to desorb nitriles from the spent adsorbent (2).

In a feed clean-up process at least two adsorbents (2, 4) are installed in front of an oligomerization reactor (3). Olefin feed is sent over one adsorbent (2) and the nitrile poisons are adsorbed so that clean feed will enter the reactor (3). Before the adsorbent (2) will be saturated, the feed (1) is sent to the other, fresh adsorbent (4). At the same time oligomerization product from the reactor (3) is used to desorb nitriles from the spent adsorbent (2).

The present invention concerns a process for oligomerizing an olefin feedstock to form an oligomerization product, and a method of controlling such an oligomerization process. The process comprises oligomerizing propylene to form a C.sub.n olefin, including contacting a feed stream comprising propylene and a recycle fraction with a solid phosphoric acid oligomerization catalyst under effective oligomerization conditions in an oligomerization reactor to produce an oligomerization effluent; and fractionating the oligomerization effluent to obtain a product fraction and the recycle fraction, the product fraction comprising the C.sub.n olefin and the recycle fraction comprising a C.sub.n-3 olefin; wherein the recycle fraction comprises at least 80 wt % of the C.sub.n-3 olefin, based on the weight of the recycle fraction; and wherein n is 9, or 12.