Prodcution of polymer/food grade solvents from paraffin rich low value streams employing hydroprocessing

Abstract

The present invention relates to the process for the preparation of Polymer/Food grade hydrocarbon solvents of naphtha range essentially free from olefins less than 20 ppm of aromatics and less than 1 ppm of sulfur from paraffinic-rich low value streams such as raffinate from the solvent extraction units in crude oil refineries employed for recovery of aromatics from reformate by hydrogenation in the presence of a nickel based catalyst.

1 . A process for preparing polymer/food grade hydrocarbon solvents of naphtha range containing very low aromatics, especially bezene less than 20 ppm from naphtha range petroleum stock, said process comprising: 
 a. heating the naphtha range petroleum feed to a temperature in the range of 70°-180° C.;    b. adding stoichiometric amount of hydrogen to the naphtha range petroleum feed at a pressure between about 5 to 30 bar;    c. passing the mixture of feed and hydrogen through a reactor having a nickel based catalyst;    d. removing any excess hydrogen to obtain the polymer/food grade hydrocarbon solvents of naphtha range containing very low aromatics.    
   
   
       2 . A process as claimed in  claim 1 , wherein the naphtha range petroleum feed is preferably raffinate from the solvent extraction units employed for recovery of aromatics from reformate.  
   
   
       3 . A process as claimed in  claim 1 , wherein the raffinate feed has sulfur<50 ppm, preferably <5 ppm and most preferably <1 ppm.  
   
   
       4 . A process as claimed in  claim 1 , wherein the raffinate feed has aromatics<20% by wt and preferably <10% by wt.  
   
   
       5 . A process as claimed in  claim 1 , wherein the raffinate feed has benzene<20% by wt and preferably <10% by wt.  
   
   
       6 . A process as claimed in  claim 1 , wherein the raffinate feed has boiling point in the range of C 5  to 110° C.  
   
   
       7 . A process as claimed in  claim 1 , wherein the raffinate feed has boiling point in the range of 63°-70° C.  
   
   
       8 . A process as claimed in  claim 1 , wherein the raffinate stream has about 4-7% by wt benzene.  
   
   
       9 . A process as claimed in  claim 1 , wherein the catalyst is nickel supported on alumina catalyst.  
   
   
       10 . A process as claimed in  claim 1 , wherein the nickel loading is about 10 to 70% by wt. and preferably is about 30 to 60% by wt.  
   
   
       11 . A process as claimed in  claim 1 , wherein the metal surface area of the nickel-alumina catalyst is about 10-20 m 2 /g.  
   
   
       12 . A process as claimed in  claim 1 , wherein the physical surface area of the nickel-alumina catalyst is about 120-200 m 2 /g and the pore volume of the catalyst is about 0.2-0.3.  
   
   
       13 . A process for producing polymer/food grade solvents of naphtha range from paraffin rich hydrocarbon streams through hydroprocessing.  
   
   
       14 . A process according to  claim 1  where in the product solvent contains nil olefins, Sulfur less than 1 ppm and aromatics, especially, Benzene less than 20 ppm.  
   
   
       15 . A process according to  claim 1  where in the Feed is low value raffinate from BTX extraction column e.g. Udex unit.  
   
   
       16 . A process according to  claim 1  where in the feed has maximum 20 wt % aromatics and 10 wt % Benzene.  
   
   
       17 . A process according to  claim 1  where in process is carried out under hydrogen environment preferably at 80-150° C., and 10 to 20 bar.  
   
   
       18 . A process according to  claim 1  where in Metals of Group. VIII supported on Inert material, preferably Ni (30-60 wt %) supported on alumina are used.  
   
   
       19 . A process according to  claim 9  where in Oxided Ni catalyst is pre-reduced before loading into the reactor.  
   
   
       20 . A process for preparing polymer/food grade hydrocarbon solvents of naphtha range containing very low aromatics such as herein described with reference to the accompanying examples.