Gazoline upgrading process

Abstract

The present invention relates to a process allowing the tuning of the gasoline/diesel balance by converting an initial feedstock containing olefins from 4 to 20 carbon atoms using a crystalline catalyst with reduced diffusional limitations. The process comprises: processing a feedstock stream containing olefins from 4 to 20 carbon atoms with or without the presence of an aromatic containing stream, contacting said stream(s) with a catalyst at conditions effective to oligomerize a least a portion of the olefins and eventually alkylate at least a portion of the aromatics, wherein the catalyst is a crystalline compound with micro/mesoporous structure chosen among crystalline aluminosilicates, crystalline aluminophosphates, crystalline silico-aluminophosphates, crystalline zeolites, or the catalyst is a composite material comprising at least 20% wt of at least one of the above mentioned crystalline compounds, and wherein the mesoporous volume of the crystalline compound is at least 0.22 ml/g.

1 . Process for the manufacture of middle distillates from a gasoline stream, said process comprising:
 processing a feedstock stream containing olefins Cn from 4 to 20 carbon atoms with or without the presence of an aromatic containing stream,   contacting said stream(s) with a catalyst at conditions effective to oligomerize a least a portion of the olefins and eventually alkylate at least a portion of the aromatics,   
       wherein the catalyst is a crystalline compound with micro/mesoporous structure chosen among crystalline aluminosilicates, crystalline aluminophosphates, crystalline silico-aluminophosphates, crystalline zeolites, or the catalyst is a composite material comprising at least 20% wt of at least one of the above mentioned crystalline compounds, and wherein the mesoporous volume of the crystalline compound is at least 0.22 ml/g, preferably at least 0.25 ml/g, and most preferably at least 0.30 ml/g, and wherein the catalyst is subjected to a treatment in an alkaline medium before use. 
     
     
         2 . Process according to  claim 1 , characterised in that the crystalline compound presents a structure of the zeolite type, preferably of the ZSM-5 type. 
     
     
         3 . Process according to  claim 1 , characterised in that the alkaline medium is a NaOH solution of concentration from 0.1 to 2 M. 
     
     
         4 . Process according to  claim 1 , characterised in that the olefin conversion is conducted at a temperature from 125 to 300° C. 
     
     
         5 . Process according to  claim 1 , characterised in that the weight hour space velocity (WHSV) of the olefin conversion is conducted from 0.5 h −1  to 5 h −1 . 
     
     
         6 . Process according to  claim 1 , characterised in that the pressure of the olefin conversion is conducted from atmospheric pressure to 200 barg. 
     
     
         7 . Process according to  claim 1 , characterised in that the feedstock is chosen among gasolines containing olefins with boiling points in the range of 30 to 100° C. or a mixture of olefins and aromatics with boiling points in the range of 30 to 170° C.