Hydrocracking process for fabricating distillate from fisher-tropsch waxes

Abstract

A method for obtaining a petroleum distillate product is provided, the method includes subjecting a Fischer-Tropsch wax to a process of hydrocraking carried out at a pressure which is substantially lower that the pressure previously used. A catalyst including a noble metal is used in this method. An apparatus for carrying out the method is also provided.

1 . A method for obtaining a petroleum distillate product comprising:
 subjecting a wax comprised of a substantially paraffin composition to hydrocracking carried out at a pressure between about 0 and about 20 Kg/cm 2  in the presence of a catalyst comprising a metal selected from a group consisting of at least one noble metal and at least one base metal; and   recovering the petroleum distillate product.   
   
   
       2 . The method of  claim 1 , wherein the wax is a Fischer-Tropsch wax. 
   
   
       3 . The method of  claim 1 , wherein the wax is a slack wax 
   
   
       4 . The method of  claim 1 , wherein the paraffin composition is comprised of at least one straight-chained paraffin and at least one branched paraffin. 
   
   
       5 . The method of  claim 4 , wherein the paraffin composition further comprises at least one cycloparaffin. 
   
   
       6 . The method of  claim 1 , wherein hydrocracking is carried out at the pressure between about 7 and about 20 Kg/cm 2 . 
   
   
       7 . The method of  claim 1 , wherein the catalyst comprises substantially spherical beads incorporating the metal. 
   
   
       8 . The method of  claim 7 , wherein the spherical beads have a diameter between about 1.5 and about 3 mm. 
   
   
       9 . The method of  claim 1 , wherein the catalyst comprises an amorphous or a zeolitic substrate and the metal is incorporated within the substrate. 
   
   
       10 . The method of  claim 1 , wherein the noble metal is selected from the group consisting of palladium, platinum, and combinations thereof. 
   
   
       11 . The method of  claim 1 , wherein the base metal is selected from the group consisting of from a group consisting of nickel, tungsten, molybdenum, and combinations thereof. 
   
   
       12 . The method of  claim 1 , wherein the petroleum distillate product comprises light ends, LPG, naphtha, kerosene, or diesel fuel. 
   
   
       13 . The method of  claim 12 , wherein between about 80 mass % and about 90 mass % of the petroleum distillate comprises a composition consisting of kerosene and diesel fuels. 
   
   
       14 . The method of  claim 1 , wherein hydrocraking includes supplying hydrogen at a rate of between about 170 and about 1,700 m 3  per 1 m 3  of the wax and/or recycled unconverted wax. 
   
   
       15 . The method of  claim 14 , wherein hydrogen is supplied at a rate of between about 675 and about 1180 m 3  per 1 m 3  of the wax and/or recycled unconverted wax. 
   
   
       16 . The method of  claim 1 , wherein hydrocracking is carried at a temperature between about 200° C. and about 425° C. 
   
   
       17 . A system for hydrocracking a wax comprised of substantially a paraffin composition, the system comprising:
 (a) a reactor ( 1 ) for hydrocracking the wax in the presence of the catalyst, the reactor generating spent catalyst and a petroleum distillate, wherein the reactor is adapted for the continuous removal of the spent catalyst;   (b) a continuous catalyst regeneration unit ( 7 ) connected to the reactor ( 1 ), wherein the continuous catalyst regeneration unit is configured for continuously accepting and regenerating the spent catalyst; and   (c) a reactor circuit in fluid communication with the reactor ( 1 ), wherein the reactor circuit is designed to maintain the pressure between about 0 and about 20 Kg/cm 2  in the reactor ( 1 ).   
   
   
       18 . The system of  claim 17 , wherein the pressure is between about 7 and about 20 Kg/cm 2 . 
   
   
       19 . The system of  claim 18 , wherein the wax is selected from a group consisting of a Fischer-Tropsch wax and a slack wax. 
   
   
       20 . The system of  claim 17 , wherein between about 80 mass % and about 90 mass % of the petroleum distillate generated in the reactor comprises a composition consisting of kerosene and diesel fuel.