OLIGOMERISATION METHOD USING RECIRCULATION OF UPPER GAS SPACE Russian patent published in 2025 - IPC C07C2/32 B01J10/00 B01J19/24 B01J4/00 

FIELD: chemistry.

SUBSTANCE: group of inventions relates to an oligomerisation method implemented in a gas-liquid reactor at pressure of 0.3 MPa to 8.0 MPa, temperature of 45 °C to 140 °C, which includes the following steps: a) a step of introducing an oligomerisation catalyst system containing a metal catalyst based on nickel, titanium or chromium and an activating agent selected from methylaluminium dichloride (MeAlCl₂), dichloroethylaluminium (EtAlCl₂), ethylaluminium sesquichloride (Et₃Al₂Cl₃), aluminum chlorodiethyl (Et₂AlCl), chlordiisobutylaluminium (i-Bu₂AlCl), triethylaluminium (AlEt₃), tripropylaluminium (Al(n-Pr)₃), triisobutylaluminium (Al(i-Bu)₃), diethylethoxyaluminium (Et₂AlOEt), methylaluminoxane (MAO), ethylaluminoxane and modified methylaluminoxanes (MMAO), into a reaction chamber comprising a liquid phase in the lower zone and a gas phase in the upper zone, b) a step of contacting said catalyst system with gaseous ethylene by introducing said ethylene into the lower zone of the reaction chamber, c) a step for collecting a liquid fraction, d) a step for cooling the liquid fraction sampled at step c) by passing said fraction into a heat exchanger, e) a step of introducing the fraction cooled in step d) into the upper part of the lower zone of the reaction chamber, f) the step of recirculating the gas fraction taken from the upper zone of the reaction chamber and introduced at the level of the lower part of the reaction chamber into the liquid phase, also relates to a reaction device for implementing the method, comprising: a reaction chamber i), elongated along a vertical axis, comprising a liquid phase in a lower zone and containing reaction products, dissolved and gaseous ethylene, a catalyst system, and a gas phase located in the upper zone above the lower zone and containing gaseous ethylene, as well as non-condensable gases; means ii) for introducing gaseous ethylene, located in the side lower part of said reaction chamber, using a means of distributing gaseous ethylene within said liquid phase of the reaction chamber; means (iii) for introducing a catalyst system containing a metal catalyst, at least one activator and at least one additive, wherein said agent is located in the lower part of the reaction chamber; recirculation circuit iv), comprising a sampling means at the base of the reaction chamber for collecting a liquid fraction into a heat exchanger, which enables to cool said liquid, and a means of introducing said cooled liquid, wherein said introduction is carried out in the liquid phase in the upper part of the lower zone of the reaction chamber; circuit (v) for returning the gas phase to the lower zone of the liquid phase, comprising a means for collecting a gas fraction at the level of the gas phase of the reaction chamber and means for introducing said collected gas fraction into the liquid phase in the lower zone of the reaction chamber.

EFFECT: group of inventions increases saturation of the liquid phase with ethylene, which increases efficiency of the oligomerisation process with shorter residence time and better selectivity with respect to hexene-1.

14 cl, 2 dwg, 2 ex