# US 10,118,875 B1 · Energy efficient methods for isomerization of a C5-C6 fraction with dividing wall fractional distillation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,118,875 B1 - Document ID: US10118875B1 - Status: Granted - Kind: B1 - Application number: 15/703,304 - Filed: 2017-09-13 - Granted: 2018-11-06 - Earliest claimed: 2017-09-13 - Applicants: David Norbert Kockler - Inventors: David Norbert Kockler - Web page: https://patentgrep.com/patent/US10118875B1 ## CPC - C07C 5/277: {Catalytic processes} - B01D 3/009: {in combination with chemical reactions} - B01D 3/141: {where at least one distillation column contains at least one dividing wall} - C07C 5/2702: {Catalytic processes not covered by C07C5/2732 - C07C5/31; Catalytic processes covered by both C07C5/2732 and C07C5/277 simultaneously} - C07C 7/04: by distillation - C10G 7/02: Stabilising gasoline by removing gases by fractioning - C10G 45/58: to change the structural skeleton of some of the hydrocarbon content without cracking the other hydrocarbons present, e.g. lowering pour point; Selective hydrocracking of normal paraffins (C10G32/00 takes precedence; improving or increasing the octane number or aromatic content of naphtha C10G35/00) - Y02P 20/10: Process efficiency - C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - C10G: CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION (cracking to hydrogen or synthesis gas C01B; cracking or pyrolysis of hydrocarbon gases to individual hydrocarbons or mixtures thereof of definite or specified constitution C07C; cracking to cokes C10B); RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract This invention relates to a method of separating an isomerization zone effluent mixture comprising between 5 and 7 carbon atoms into high octane isomerate product streams and low octane streams which may be recycled to the isomerization zone. The separation process makes use of a dividing wall column to efficiently perform the separation of isopentane and high octane multibranched paraffins from low octane straight chain and single branched paraffins. ## Claims ### Claim 1 An isomerization process having an isomerized product fractionation zone, said process comprising: contacting a combined isomerization zone feed comprising at least normal pentane and normal hexane with an isomerization catalyst in an isomerization zone to isomerize at least a portion of the normal pentane and normal hexane and form an isomerization zone effluent comprising at least C5-C6 normal and branched paraffins; passing the isomerization zone effluent into an isomerized product fractionation zone comprising a stabilizer and a dividing wall column, wherein the isomerization zone effluent is passed into a stabilizer to remove butane and light gases and form a stabilized isomerized product; passing the stabilized isomerized product into a dividing wall column divided into at least a first and second parallel fractionation zones by a dividing wall, with the first and second fractionation zones each having an upper end and a lower end located within the dividing wall column, wherein the first and second parallel fractionation zones are in open communication at the upper ends with an undivided upper section of the column and wherein the first and second parallel fractionation zones are in open communication at the lower ends with an undivided lower section of the column, and wherein the stabilized isomerized product enters the column at an intermediate point in the first parallel fractionation zone; and removing at least three streams from the dividing wall column, wherein at least one side stream comprising normal pentane and paraffins containing 6 carbon atoms with at least two branches is removed from an intermediate point of the second parallel fractionation zone of the dividing wall column, and wherein a high octane stream comprising isopentane is removed from a first end of the dividing wall column. ### Claim 2 (depends on 1) The process according to claim 1, wherein said side stream is passed into a non-divided column. ### Claim 3 (depends on 2) The process according to claim 2, wherein a low octane stream comprising normal pentane is removed from a first end of the non-divided column; and wherein a high octane stream comprising paraffins containing 6 carbon atoms with at least two branches is removed from a second end of the non-divided column. ### Claim 4 (depends on 1) The process according to claim 1, wherein a high octane stream comprising hydrocarbons containing at least 7 carbon atoms is removed from a second end of the dividing wall column. ### Claim 5 (depends on 1) The process according to claim 1, wherein a low octane stream comprising normal hexane and paraffins containing 6 carbon atoms and a single branch is removed as a side stream from an intermediate point in the undivided lower section of the dividing wall column. ### Claim 6 (depends on 1) The process according to claim 1, further comprising passing an isomerization feed to a feed fractionation zone to separate a stream rich in molecules containing 5 carbon atoms comprising isopentane and passing said stream to the dividing wall column as a second feed to the dividing wall column, wherein said stream enters the dividing wall column at an intermediate point in the undivided upper section of the dividing wall column and wherein a remainder of the isomerization feed is passed to the isomerization zone as at least a part of the combined isomerization feed. ### Claim 7 (depends on 1) The process according to claim 1, further comprising passing an isomerization feed to a feed fractionation zone to separate a stream rich in molecules containing 5 carbon atoms comprising isopentane and passing said stream to the dividing wall column as a second feed to the dividing wall column, wherein said stream enters the dividing wall column at an intermediate point in the first parallel fractionation zone and wherein a remainder of the isomerization feed is passed to the isomerization zone as at least a part of the combined isomerization feed. ### Claim 8 An isomerization process having an isomerized product fractionation zone, said process comprising: contacting a combined isomerization zone feed comprising at least normal pentane and normal hexane with an isomerization catalyst in an isomerization zone to isomerize at least a portion of the normal pentane and normal hexane and form an isomerization zone effluent comprising at least C5-C6 normal and branched paraffins; passing the isomerization zone effluent into an isomerized product fractionation zone comprising a stabilizer and a dividing wall column, wherein the isomerization zone effluent is passed into a stabilizer to remove butane and light gases and form a stabilized isomerized product; passing the stabilized isomerized product into a dividing wall column divided into at least a first and second parallel fractionation zones by a dividing wall, with the first and second fractionation zones each having an upper end and a lower end located within the dividing wall column, wherein the first and second parallel fractionation zones are in open communication at the upper ends with an undivided upper section of the column and wherein the first and second parallel fractionation zones are in open communication at the lower ends with an undivided lower section of the column, and wherein the stabilized isomerized product enters the column at an intermediate point in the first parallel fractionation zone; and removing at least four streams from the dividing wall column, wherein a low octane stream comprising normal pentane is removed as a first side stream from the second parallel fractionation zone of the dividing wall column and a high octane stream comprising paraffins containing 6 carbon atoms with at least two branches is removed as a second side stream from the second parallel fractionation zone of the dividing wall column, and wherein a high octane stream comprising isopentane is removed from a first end of the dividing wall column. ### Claim 9 (depends on 8) The process according to claim 8, wherein a high octane stream comprising hydrocarbons containing at least 7 carbon atoms is removed from a second end of the dividing wall column. ### Claim 10 (depends on 8) The process according to claim 8, wherein a low octane stream comprising normal hexane and paraffins containing 6 carbon atoms and a single branch is removed as a side stream from an intermediate point in the undivided lower section of the dividing wall column. ### Claim 11 (depends on 8) The process according to claim 8, further comprising passing an isomerization feed to a feed fractionation zone to separate a stream rich in molecules containing 5 carbon atoms comprising isopentane and passing said stream to the dividing wall column as a second feed to the dividing wall column, wherein said stream enters the dividing wall column at an intermediate point in the undivided upper section of the dividing wall column and wherein a remainder of the isomerization feed is passed to the isomerization zone as at least a part of the combined isomerization feed. ### Claim 12 (depends on 8) The process according to claim 8, further comprising passing an isomerization feed to a feed fractionation zone to separate a stream rich in molecules containing 5 carbon atoms comprising isopentane and passing said stream to the dividing wall column as a second feed to the dividing wall column, wherein said stream enters the dividing wall column at an intermediate point in the first parallel fractionation zone and wherein a remainder of the isomerization feed is passed to the isomerization zone as at least a part of the combined isomerization feed. ### Claim 13 A process for separating an isomerization zone effluent in a product fractionation zone comprising a stabilizer and a dividing wall column, comprising: passing an isomerization zone effluent comprising at least C5-C6 normal and branched paraffins to a stabilizer to remove butane and light gases and form a stabilized isomerized product; passing the stabilized isomerized product into a dividing wall column divided into at least a first and second parallel fractionation zones by a dividing wall, with the first and second fractionation zones each having an upper end and a lower end located within the dividing wall column, wherein the first and second parallel fractionation zones are in open communication at the upper ends with an undivided upper section of the column and wherein the first and second parallel fractionation zones are in open communication at the lower ends with an undivided lower section of the column, and wherein the stabilized isomerized product enters the column at an intermediate point in the first parallel fractionation zone; and removing at least three streams from the dividing wall column, wherein at least one side stream comprising normal pentane and paraffins containing 6 carbon atoms with at least two branches is removed from an intermediate point of the second parallel fractionation zone of the dividing wall column, and wherein a high octane stream comprising isopentane is removed from a first end of the dividing wall column.