A membrane process for the removal of sulfur species from a naphtha feed, in particular, a FCC light cat naphtha, without a substantial loss of olefin yield is disclosed. The process involves contacting a naphtha feed stream with a membrane having sufficient flux and selectivity to separate a sulfur deficient retentate fraction from a sulfur enriched permeate fraction, preferably, under pervaporation conditions. Sulfur deficient retentate fractions are useful directly into the gasoline pool. Sulfur-enriched permeate fractions are rich in sulfur containing aromatic and nonaromatic hydrocarbons and are further treated with conventional sulfur removal technologies, e.g. hydrotreating, to reduce sulfur content. The process of the invention provides high quality naphtha products having a reduced sulfur content and a high content of olefin compounds.

Claims

60 · 3 independent · depth 4

60 granted claims

›1.independentA method for lowering the sulfur content of a naphtha hydrocarbon feed stream while substantially maintaining the yield of olefin compounds in the fee…+19

›2.↳ 1The method of claim 1 wherein the membrane is one having a sulfur enrichment factor of greater than 1.5.d2+2

›3.↳ 1The method of claim 1 wherein the sulfur content of the sulfur deficient retentate fraction is less than 100 ppm.d2+2

›6.↳ 1The method of claim 1 wherein the naphtha feed stream is a cracked naphtha.d2+2

›9.↳ 1The method of claim 1 wherein the naphtha is a coker naphtha.d2

›10.↳ 1The method of claim 1 wherein the naphtha is a straight run naphtha.d2

›11.↳ 1The method of claim 1 wherein the sulfur deficient retentate fraction comprises at least 50 wt % of the total feed.d2+1

›13.↳ 1The method of claim 1 wherein the non-membrane process of step (iii) comprises a hydrotreating process.d2

›14.↳ 1The method of claim 1 wherein the non-membrane process of step (iii) comprises an adsorption process.d2

›15.↳ 1The method of claim 1 wherein the non-membrane process of step (iii) comprises a catalytic distillation process.d2

›18.↳ 1The method of claim 1 wherein the sulfur deficient retentate fraction contains from about 50 to about 90 wt % of olefin compounds present in the initi…d2

›19.↳ 1The method of claim 1 further comprising combining the sulfur deficient retentate product stream and the reduced sulfur permeate product stream.d2

›20.↳ 1The method of claim 1 wherein the total amount of olefin compounds present in the retentate product stream and the permeate product stream is at least…d2

›21.independentA method for lowering the sulfur content of a naphtha hydrocarbon feed stream while substantially maintaining the yield of olefin compounds in the fee…+19

›22.↳ 21The method of claim 21 wherein the membrane is one having a sulfur enrichment factor of greater than 1.5.d2+1

›23.↳ 21The method of claim 21 wherein the sulfur content of the sulfur deficient retentate fraction is less than 100 ppm.d2+2

›26.↳ 21The method of claim 21 wherein the naphtha feed stream is a cracked naphtha.d2+2

›29.↳ 21The method of claim 21 wherein the naphtha is a coker naphtha.d2

›30.↳ 21The method of claim 21 wherein the naphtha is a straight run naphtha.d2

›31.↳ 21The method of claim 21 wherein the sulfur deficient retentate fraction comprises at least 50 wt % of the total feed.d2

›32.↳ 21The method of claim 21 wherein the sulfur deficient retentate fraction comprises at least 70 wt % of the total feed.d2

›33.↳ 21The method of claim 21 wherein the non-membrane process of step (iii) comprises a hydrotreating process.d2

›34.↳ 21The method of claim 21 wherein the non-membrane process of step (iii) comprises an adsorption process.d2

›35.↳ 21The method of claim 21 wherein the non-membrane process of step (iii) comprises a catalytic distillation process.d2

›36.↳ 21The method of claim 21 wherein the membrane has a sulfur enrichment factor of greater than 2.d2

›38.↳ 21The method of claim 21 wherein the sulfur deficient retentate fraction contains from about 50 to about 90 wt % of olefin compounds present in the init…d2

›39.↳ 21The method of claim 21 further comprising combining the sulfur deficient retentate product stream and the reduced sulfur permeate product stream.d2

›40.↳ 21The method of claim 21 wherein the total amount of olefin compounds present in the retentate product stream and the permeate product stream is at leas…d2

›41.independentA method for lowering the sulfur content of a naphtha hydrocarbon feed stream while substantially maintaining the yield of olefin compounds in the fee…+19

›42.↳ 41The method of claim 41 wherein the membrane is one having a sulfur enrichment factor of greater than 1.5.d2

›43.↳ 41The method of claim 41 wherein the sulfur content of the sulfur deficient retentate fraction is less than 100 ppm.d2+2

›46.↳ 41The method of claim 41 wherein the naphtha feed stream is a cracked naphtha.d2+2

›49.↳ 41The method of claim 41 wherein the naphtha is a coker naphtha.d2

›50.↳ 41The method of claim 41 wherein the naphtha is a straight run naphtha.d2

›51.↳ 41The method of claim 41 wherein the sulfur deficient retentate fraction comprises at least 50 wt % of the total feed.d2+1

›53.↳ 41The method of claim 41 wherein the non-membrane process of step (iii) comprises a hydrotreating process.d2

›54.↳ 41The method of claim 41 the non-membrane process of step (iii) comprises an adsorption process.d2

›55.↳ 41The method of claim 41 wherein the non-membrane process of step (iii) comprises a catalytic distillation process.d2

›56.↳ 41The method of claim 41 wherein the membrane has a sulfur enrichment factor of greater than 2.d2+1

›58.↳ 41The method of claim 41 wherein the sulfur deficient retentate fraction contains from about 50 to about 90 wt % of olefin compounds present in the init…d2

›59.↳ 41The method of claim 41 further comprising combining the sulfur deficient retentate product stream and the reduced sulfur permeate product stream.d2

›60.↳ 41The method of claim 41 wherein the total amount of olefin compounds present in the retentate product stream and the permeate product stream is at leas…d2

Classifications

5 codes

IPC · International Patent Classification

Section C — Chemistry; metallurgy

C10G3/100

USPC · US Patent Classification

208/208.R208/211585/818210/649

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Type	Document	Date
related publication	US 20020153284 A1	24 Oct 2002

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