System and method for producing un-hydrogenated and hydrogenated c9+ compounds

Abstract

A system and method for processing pyrolysis gasoline is disclosed. The system and method involves separating a pyrolysis gasoline stream to produce a first stream comprising primarily un-hydrogenated C9+ compounds. The separating of the pyrolysis e gasoline occurs without hydrogenation being carried out on the pyrolysis gasoline before the separating.

1 . A method of processing pyrolysis gasoline, the method comprising:
 separating a pyrolysis gasoline stream to produce a first stream comprising primarily un-hydrogenated C 9+  compounds.   
     
     
         2 . The method of  claim 1  wherein the first stream comprises 98 to 100 wt. % C 9+  compounds. 
     
     
         3 . The method of  claim 1  further comprising:
 hydrogenating a portion of the first stream to produce a second stream comprising hydrogenated C 9+  hydrogenated compounds. 
 
     
     
         4 . The method of  claim 3 , wherein the hydrogenating of the first portion of the first stream is carried out under reaction conditions comprising a temperature in a range of 100° C. to 200° C., a pressure in a range of 10 bar to 30 bar, a WHSV of 2 h −1  to 8 h −1 , and in the presence of a catalyst comprising Ni/Al 2 O 3  to Pd/Al 2 O 3 . 
     
     
         5 . The method of  claim 3  further comprising:
 separating the second stream to produce a third stream comprising hydrogenated wash oil and a fourth stream comprising hydrogenated C 9+  residue. 
 
     
     
         6 . The method of  claim 5  wherein third stream comprises 0 to 90 wt. % wash oil and the fourth stream comprises 10 to 100 wt. % hydrogenated C 9+  compounds. 
     
     
         7 . The method of  claim 5 , further comprising:
 subjecting the third stream to reaction conditions to hydrogenate the third stream.   
     
     
         8 . The method of  claim 1 , wherein the separating of the pyrolysis gasoline stream comprises:
 distilling the pyrolysis gas stream in a depentanizer column to produce a fifth stream comprising primarily C 4+  compounds and a sixth stream comprising primarily C 6+  compounds.   
     
     
         9 . The method of  claim 8  wherein the separating of the pyrolysis gasoline stream further comprises:
 distilling the sixth stream in a deoctanizer column to produce a seventh stream comprising primarily C 6  to C 8  compounds and the first stream. 
 
     
     
         10 . The method of  claim 9  comprising:
 hydrogenating the seventh stream to produce an eighth stream comprising benzene, toluene, and xylene. 
 
     
     
         11 . The method of  claim 10 , wherein the hydrogenating of the seventh stream is carried out under reaction conditions comprising a temperature in a range of 100° C. to 200° C., a pressure in a range of 10 bar to 30 bar, a WHSV of 2 h −1  to 8 h −1 , and in presence of a catalyst comprising Ni/Al 2 O 3  to Pd/Al 2 O 3 . 
     
     
         12 . The method of  claim 8  further comprising:
 processing the fifth stream in a stabilizer to produce a ninth stream comprising fuel gas and a tenth stream comprising primarily C 4  and C 5  compounds. 
 
     
     
         13 . The method of  claim 12  further comprising:
 hydrogenating the tenth stream to produce an eleventh stream comprising primarily C 4  and C 5  compounds. 
 
     
     
         14 . The method of  claim 13 , wherein the hydrogenating of the tenth stream is carried out under reaction conditions comprising a temperature in a range of 40° C. to 140° C., a pressure in a range of 20 bar to 40 bar, a WHSV of 10 h −1  to 16 h −1 , and in presence of a catalyst comprising Ni/Al 2 O 3  to Pd/Al 2 O 3 . 
     
     
         15 . The method of  claim 13  further comprising subjecting the eleventh stream to cracking conditions to form C 2  to C 4  light olefins, LPG, and H 2 . 
     
     
         16 . A method of processing pyrolysis gasoline, the method comprising:
 concurrently producing (1) a first stream comprising primarily un-hydrogenated C 9+  compounds and (2) a second stream comprising hydrogenated C 9+  hydrogenated compounds, wherein the producing comprises separating a pyrolysis gasoline stream to produce the first stream comprising primarily un-hydrogenated C 9+  compounds and hydrogenating a portion of the first stream to produce the second stream comprising hydrogenated C 9+  hydrogenated compounds.   
     
     
         17 . The method of  claim 16  further comprising:
 producing a stream comprising primarily un-hydrogenated C 4+  compounds. 
 
     
     
         18 . A method of processing pyrolysis gasoline, the method comprising:
 separating a pyrolysis gasoline stream to produce a first stream comprising primarily un-hydrogenated C 9+  compounds;   hydrogenating a portion of the first stream to produce a second stream comprising hydrogenated C 9+  compounds;   separating the second stream to produce a third stream comprising hydrogenated wash oil and a fourth stream comprising hydrogenated C 9+  residue, wherein the separating of the pyrolysis gasoline stream comprises:
 distilling the pyrolysis gas stream in a depentanizer column to produce a fifth stream comprising primarily C 4+  compounds and a sixth stream comprising primarily C 6+  compounds; 
 distilling the sixth stream in a deoctanizer column to produce a seventh stream comprising primarily C 6  to C 8  compounds and the first stream; 
   processing the fifth stream in a stabilizer to produce a ninth stream comprising fuel gas and a tenth stream comprising primarily C 4  and C 5  compounds;   and   combining the third stream, the seventh stream, and the tenth stream to form a combined stream and flowing the combined stream to a reactor.   
     
     
         19 . The method of  claim 18 , further comprising:
 subjecting the combined stream to reaction conditions sufficient to form a reactor effluent.   
     
     
         20 . The method of  claim 19  further comprising:
 processing the reactor effluent to produce a BTX stream, a stream comprising primarily hydrogenated wash oil, a fuel gas stream and a stream comprising primarily C 5  compounds.