Process for producing gasoline of increased octane and hydrogen-containing co-produced stream

Abstract

The present invention is directed to a process for producing an increased yield of gasoline of increased octane rating by the integration of a membrane separation processing step into the gasoline production process. The integrated process also increases hydrogen production from the reformer.

1 . A method for producing gasoline or gasoline blending stock of increased octane rating while also producing a hydrogen stream with increased hydrogen yield comprising contacting a feed stream containing a mixture of aromatic hydrocarbons and non-aromatic hydrocarbons with a membrane in a membrane separation unit wherein the feed is separated into an aromatics-rich/saturates-lean permeate which is a gasoline or gasoline blending stock of increased octane rating and a retentate stream of reduced aromatics content/increased non-aromatics content which is used as feed stream to a reformer wherein the retentate stream is converted in the reformer into high octane reformer gasoline and a gaseous stream of co-produced hydrogen. 
   
   
       2 . The method of  claim 1  wherein the feed to the membrane separation unit is selected from virgin naphtha stream, thermal cracked naphtha stream, catalytically cracked naphtha stream, a stream boiling in the distillate to gasoline boiling range containing aromatic and non-aromatic hydrocarbons, or mixtures thereof. 
   
   
       3 . The method of  claim 2  wherein the stream is virgin naphtha, thermal cracked naphtha, catalytically cracked naphtha or mixtures thereof. 
   
   
       4 . The method of  claim 1  wherein the reformer unit is a continuous catalytic reformer or a semi-regenerated reformer. 
   
   
       5 . The method of  claim 4  wherein the stream sent to the reformer comprises the retentate stream from the membrane separation unit combined with other saturates-rich/aromatics-lean refinery streams typically used as reformer feed streams. 
   
   
       6 . The method of  claim 4  wherein the retentate sent to the reformer is a combined stream comprising retentate from the membrane separation unit and a retentate from a different membrane separation unit operating on an aromatics/non-aromatics containing feed stream previously subjected to a FCC naphtha desulfurization process. 
   
   
       7 . The method of  claim 1  wherein the feed is a naphtha feed previously subjected to hydrotreating in a catalytic naphtha hydrotreater. 
   
   
       8 . The method of  claim 1  wherein the feed to the reformer is a combined stream comprising retentate from the membrane separation unit and an effluent stream from a hydrotreater unit which has hydrotreated a feed comprising naphtha. 
   
   
       9 . The method of  claim 8  wherein the retentate from the membrane separation unit is retentate recovered from the unit operating on a feed comprising hydrocrackate, cracked naphtha or mixtures thereof. 
   
   
       10 . The method of  claim 8  wherein the naphtha feed to the hydrotreater is virgin naphtha, thermal cracked naphtha, catalytically cracked naphtha, a naphtha produced from a hydroprocessing unit, or mixtures thereof. 
   
   
       11 . The method of  claim 1 , further comprising:
 providing a second feed stream corresponding to a heavy catalytic naphtha feedstream;   hydrotreating the heavy catalytic naphtha under effective hydrotreating conditions;   contacting the hydrotreated heavy catalytic naphtha with a membrane to concentrate aromatics in the permeate and increase octane rating/quality while producing a retentate suitable for use as a diesel fuel or a jet fuel.