# US 2025/0084014 A1 · Oligomerisation process comprising a step of recycling a pre-cooled solvent > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0084014 A1 - Document ID: US20250084014A1 - Status: Published application - Kind: A1 - Application number: 18/284,606 - Filed: 2022-03-25 - Published: 2025-03-13 - Earliest claimed: 2021-03-30 - Assignees: Ifp Energies Nouvelles - Applicants: Ifp Energies Nouvelles - Inventors: Pierre-Alain BREUIL; Olivier COTTE - Web page: https://patentgrep.com/patent/US20250084014A1 ## CPC - C07C 2/04: by oligomerisation of well-defined unsaturated hydrocarbons without ring formation - C07C 2/08: Catalytic processes - C07C 7/04: by distillation - C07C 11/08: with four carbon atoms - C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS ## Abstract The present invention relates to a process for the oligomerization of an olefinic feedstock characterized in that a solvent fraction resulting from a downstream separation step is cooled and recycled. ## Claims ### Claim 1 A process for the oligomerization of an olefinic feedstock carried out at a temperature between 30° C. and 200° C. and a pressure between 0.1 and 10 MPa, in the presence of a homogeneous catalytic oligomerization system and a solvent, said process comprising; a) a step of oligomerizing said olefinic feedstock in a reaction section comprising an oligomerization reactor and one or more recirculation loops enabling the control of the temperature in said reactor via the cooling of a liquid phase fraction, b) a step of separating, in a downstream separation section, a reaction effluent resulting from the oligomerization step a) so as to obtain a solvent fraction, c) a step of cooling the solvent fraction resulting from step b) to a temperature below the temperature of the recirculation loop(s), and d) a step of introducing, into the oligomerization step a), the cooled solvent fraction resulting from step c) in the reaction section. ### Claim 2 (depends on 1) The process as claimed in claim 1, wherein the solvent fraction resulting from step b) is cooled to a temperature between 0° C. and 150° C. ### Claim 3 (depends on 1) The process as claimed in claim 1, wherein the solvent fraction resulting from step b) is cooled in step c) to a temperature at least 40° C. lower relative to the temperature of the cooled liquid fraction in the recirculation loop. ### Claim 4 (depends on 1) The process as claimed in claim 1, wherein the cooling of the solvent fraction in step c) is carried out by one or more thermal exchangers. ### Claim 5 (depends on 1) The process as claimed in claim 1, wherein the downstream separation section comprises at least two distillation columns. ### Claim 6 (depends on 1) The process as claimed in claim 1, wherein step d) of introducing the cooled solvent fraction is carried out in the reactor and/or in one or more of the recirculation loops. ### Claim 7 (depends on 4) The process as claimed in claim 4, wherein step d) of introducing the cooled fraction is carried out in a recirculation loop upstream or downstream of a thermal exchanger of said recirculation loop. ### Claim 8 (depends on 1) The process as claimed in claim 1, wherein the cooled solvent fraction has a flow rate, as a weight percentage relative to the flow rate of the liquid circulating in the circulation loop(s), of between 0.05% and 15.0%. ### Claim 9 (depends on 1) The process according to claim 1, wherein the olefinic feedstock comprises olefins having between 2 and 6 carbon atoms. ### Claim 10 (depends on 9) The process as claimed in claim 9, wherein the olefinic feedstock is chosen from butene, propylene and ethylene, alone or as a mixture. ### Claim 11 (depends on 1) The process as claimed in claim 1, wherein the oligomerization step a) comprises at least one of the following substeps: substep a1) of introducing the catalytic system, substep a2) of bringing into contact with olefinic feedstock, substep a3) of withdrawing a liquid phase fraction from the oligomerization reactor, substep a4) of cooling at least one portion of the liquid fraction withdrawn in step a3), and substep a5) of introducing the cooled liquid fraction into the reactor. ### Claim 12 (depends on 11) The process as claimed in claim 11, wherein the cooling substep a4) is carried out by circulating at least one portion of the liquid fraction withdrawn in substep a3) through one or more thermal exchangers located in the recirculation loop. ### Claim 13 (depends on 12) The process as claimed in claim 12, wherein the thermal exchanger(s) used in substep a4) reduce(s) the temperature of the liquid fraction by 1.0° C. to 30.0° C., preferably between 2.0° C. and 25.0° C. ### Claim 14 (depends on 11) The process as claimed in claim 11, wherein the reaction effluent is obtained by dividing the liquid fraction withdrawn in substep a3) into two streams. ### Claim 15 (depends on 1) The process as claimed in claim 1, wherein the oligomerization reactor is chosen from a two-phase gas/liquid reactor or a single-phase liquid reactor, preferably is a two-phase gas/liquid reactor, and very preferably of bubble column type. ### Claim 16 (depends on 1) The process as claimed in claim 1, wherein the cooling of the solvent fraction in step c) is carried out by one or more heat exchangers selected from process fluid/process fluid heat exchangers, air cooler heat exchangers, and cooling water heat exchangers. ### Claim 17 (depends on 1) The process as claimed in claim 1, wherein the downstream separation section comprises at least three distillation columns. ### Claim 18 (depends on 4) The process as claimed in claim 4, wherein step d) of introducing the cooled fraction is carried out in a recirculation loop downstream of a thermal exchanger of said recirculation loop. ### Claim 19 (depends on 1) The process as claimed in claim 1, wherein the cooled solvent fraction has a flow rate, as a weight percentage relative to the flow rate of the liquid circulating in the circulation loop(s), of between 0.1% and 10.0%. ### Claim 20 (depends on 1) The process according to claim 1, wherein the olefinic feedstock comprises olefins having between 2 and 4 carbon atoms.