Manufacture of xylenes using reformate
AssigneeExxonMobil Chemical Patents Inc.
InventorsLarry L. Iaccino, Jeevan S. Abichandani, John Scott Buchanan, Robert A. Crane, Jihad M. Dakka, Xiaobing Feng, Shifang L. Luo, Gary D. Mohr
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Abstract
A process is provided for the production of xylenes from reformate. The process is carried out by methylating under conditions effective for the methylation, the benzene/toluene present in the reformate outside the reforming loop, to produce a resulting product having a higher xylenes content than the reformate. Greater than equilibrium amounts of para-xylene can be produced by the process.
Claims26
An process for producing xylenes from naphtha, which process comprises the steps of:
- (a) aromatizing naphtha in an aromatization zone under aromatization conditions and the presence of a first catalyst effective for the aromatization of the naphtha to produce a reformate containing hydrogen, C1-C5 hydrocarbons, C6-C7 hydrocarbons comprising benzene, toluene or mixtures thereof, and C8+ hydrocarbons;
- (b) removing at least a portion of said hydrogen from said reformate to produce a first product having less hydrogen content than said reformate;
- (c) removing at least a portion of said C1-C5 hydrocarbons from said first product in a C1-C5 hydrocarbon separation zone to produce a second product having less C1-C5 hydrocarbon content than said first product;
- (d) removing at least a portion of said C8+ hydrocarbons from said second product in a C8+ hydrocarbon separation zone to produce a third product having less C8+ hydrocarbon content than said second product;
- (e) transferring at least a portion of said third product to a methylation reaction zone;
- and
- (f) methylating in said methylation reaction zone at least a portion of the benzene, toluene, or mixtures thereof present in said third product with a methylating agent under vapor phase conditions effective for the methylation and in the presence of a second catalyst effective for the methylation to produce a fourth product having a higher xylenes content than said reformate, wherein said second catalyst comprises a zeolite-bound-zeolite catalyst, a selectivated zeolite, ZSM-23, or a mixture thereof, and wherein said zeolite in said zeolite-bound-zeolite catalyst or said selectivated zeolite comprises ZSM-5.
An integrated process for producing xylenes from naphtha which process comprises the steps of:
- (a) aromatizing naphtha in an aromatization zone under aromatization conditions and the presence of a first catalyst effective for the aromatization of the naphtha to produce a reformate containing hydrogen, C1-C5 hydrocarbons, C6-C7 hydrocarbons comprising benzene, toluene or mixtures thereof, and C8+ hydrocarbons;
- (b) removing at least a portion of said hydrogen from said reformate to produce a first product having less hydrogen content than said reformate;
- (c) removing at least a portion of said C8+ hydrocarbons from said first product in a C8+ hydrocarbon separation zone to produce a second product having less C8+ hydrocarbon content than said first product;
- (d) transferring at least a portion of said second product to a methylation reaction zone;
- and,
- (e) methylating in said methylation reaction zone at least a portion of the benzene, toluene, or mixtures thereof present in said second with a methylating agent under conditions effective for the methylation and in the presence of a second catalyst effective for the methylation to produce a third product having a higher xylenes content than said reformate, wherein said second catalyst comprises a zeolite-bound-zeolite catalyst, a selectivated zeolite, ZSM-23, or a mixture thereof, and wherein said zeolite in said zeolite-bound-zeolite catalyst or said selectivated zeolite comprises ZSM-5.
Dependencies are inferred from the claim text.