# US 2013/0158334 A1 · Process and Apparatus for para-Xylene Production using Multiple Adsorptive Separation Units > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0158334 A1 - Document ID: US20130158334A1 - Status: Published application - Kind: A1 - Application number: 13/326,906 - Filed: 2011-12-15 - Published: 2013-06-20 - Earliest claimed: 2011-12-15 - Assignees: Uop LLC - Inventors: Jason T. Corradi - Web page: https://patentgrep.com/patent/US20130158334A1 ## CPC - C07C 5/2729: {Changing the branching point of an open chain or the point of substitution on a ring} - C07C 7/005: {Processes comprising at least two steps in series} - C07C 7/12: by adsorption, i.e. purification or separation of hydrocarbons with the aid of solids, e.g. with ion-exchangers - C07C 7/148: by treatment giving rise to a chemical modification of at least one compound - B01J 2219/00006: Large-scale industrial plants - C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS ## Abstract A process for separating para-xylene from a plurality of aromatic compounds, wherein the process introduces a mixed xylene feed stream comprising a plurality of xylene isomers into a first separation assembly to produce a first para-xylene enriched stream and a first raffinate stream. The process further feeds the raffinate stream into an isomerization unit to convert the raffinate stream into an isomerization reactor product stream, and introduces the isomerization reactor product stream into to a second para-xylene adsorptive separation unit to produce a second para-xylene enriched stream and a second raffinate stream. ## Claims ### Claim 1 A process for separating para-xylene from a plurality of aromatic compounds, the process comprising: introducing a mixed xylene stream comprising a plurality of xylene isomers into a first separation assembly and producing a first para-xylene enriched stream and a first raffinate stream; feeding said first raffinate stream into an isomerization unit to convert said first raffinate stream into an isomerization reactor product stream; and introducing the isomerization reactor product stream into a second separation assembly and producing a second para-xylene enriched stream and a second raffinate stream. ### Claim 2 (depends on 1) The process of claim 1, wherein: said introducing a mixed xylene stream comprises introducing the mixed xylene feed stream and a first desorbent stream into a first adsorptive separation unit disposed within the first separation assembly; and said introducing the isomerization reactor product stream comprises introducing an isomerization reactor product stream and a second desorbent stream into a second adsorptive separation unit disposed within the second separation assembly. ### Claim 3 (depends on 2) The process of claim 2, wherein the first desorbent stream differs from the second desorbent stream. ### Claim 4 (depends on 3) The process of claim 3, wherein: the first desorbent stream comprises a desorbent selected from the group consisting of para-diethylbenzene, para-diisopropylbenzene, and tetralin; and the second desorbent stream comprises toluene. ### Claim 5 (depends on 1) The process of claim 1, further comprising feeding a first mixed aromatic feed stream comprising a plurality of aromatic compounds into a xylene fractionation unit to produce said mixed xylene stream. ### Claim 6 (depends on 5) The process of claim 5, wherein the isomerization reactor product stream is not introduced into the xylene fractionation unit. ### Claim 7 (depends on 5) The process of claim 5, further comprising introducing the second para-xylene enriched stream into the first separation assembly. ### Claim 8 (depends on 7) The process of claim 7, wherein introducing the second para-xylene enriched stream comprises introducing the second para-xylene enriched stream into the first adsorptive separation unit. ### Claim 9 (depends on 5) The process of claim 5, further comprising introducing a drag stream derived from the second raffinate stream into the xylene fractionation unit. ### Claim 10 (depends on 5) The process of claim 5, further comprising: introducing a drag stream derived from the second raffinate stream into an aromatic conversion unit and producing a second mixed aromatic stream; and introducing the second mixed aromatic stream into the xylene fractionation unit. ### Claim 11 An apparatus for separating para-xylene from a plurality of aromatic compounds, comprising: a first separation assembly comprising a first adsorptive separation unit; a second separation assembly comprising a second adsorptive separation unit; and an isomerization unit in fluid communication with both said first separation assembly and said second separation assembly. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein: said first separation assembly comprises a finishing column; and said second separation assembly does not comprise a finishing column. ### Claim 13 (depends on 11) The apparatus of claim 11, further comprising a xylene fractionation column in fluid communication with the first separation assembly. ### Claim 14 (depends on 13) The apparatus of claim 13, further comprising a drag line, wherein the drag line places the second separation assembly in fluid communication with the xylene fractionation unit. ### Claim 15 (depends on 13) The apparatus of claim 13, further comprising an aromatic conversion unit in fluid communication with the xylene fractionation column and the second separation assembly. ### Claim 16 (depends on 11) The apparatus of claim 11, wherein the first separation assembly further comprises: a first raffinate column in fluid communication with the first adsorptive separation unit; and a first extract column in fluid communication with both the first adsorptive separation unit and the finishing column. ### Claim 17 (depends on 16) The apparatus of claim 16, wherein the second separation assembly further comprises a second raffinate column and a second extract column, each in fluid communication the second adsorptive separation unit. ### Claim 18 (depends on 11) The apparatus of claim 11, wherein the first separation assembly further comprises a first desorbent loop. ### Claim 19 (depends on 18) The apparatus of claim 18, wherein the second separation assembly further comprises a second desorbent loop. ### Claim 20 (depends on 19) The apparatus of claim 19, wherein the first desorbent loop transfers para-diethlybenzene and the second desorbent loop transfers toluene.