Process for preparing purified fischer-tropsch gasoil fraction

Abstract

The present invention provides a process for preparing a high purity Fischer-Tropsch gasoil fraction, comprising : a) providing a Fischer-Tropsch-derived gasoil feedstock comprising one or more contaminants; b) providing the Fischer-Tropsch-derived gasoil feedstock to a fractionation zone and fractionating the Fischer-Tropsch-derived gasoil feedstock into two or more Fischer-Tropsch gasoil fractions having a different boiling point range, wherein at least one Fischer-Tropsch gasoil fraction is a contaminant-containing Fischer- Tropsch gasoil fraction; c) providing the contaminant-containing Fischer-Tropsch gasoil fraction to an absorption zone comprising at least one absorbent material and contacting the contaminant-containing Fischer-Tropsch gasoil fraction with the absorbent material to absorb at least part of contaminant; and d) retrieving from the absorption zone a purified Fischer-Tropsch gasoil fraction, which is contaminant-depleted. The invention further provides for the use of the purified Fischer-Tropsch gasoil fraction.

1 . A process for preparing a purified Fischer-Tropsch gasoil fraction, comprising:
 a) providing a Fischer-Tropsch-derived gasoil feedstock comprising one or more contaminants, wherein said Fischer-Tropsch-derived gasoil is a fluid comprising paraffins, including isoparaffins and normal paraffins, with alkyl chain lengths in the range of from 7 to 30 carbon atoms, comprising at least 70 wt % of Fischer-Tropsch-derived paraffins having 9 to 25 carbon atoms based on the total amount of Fischer-Tropsch-derived paraffins;   b) providing the Fischer-Tropsch-derived gasoil feedstock to a fractionation zone and fractionating the Fischer-Tropsch-derived gasoil feedstock into two or more Fischer-Tropsch gasoil fractions having a different boiling point range, wherein at least one Fischer-Tropsch gasoil fraction is a contaminant-containing Fischer-Tropsch gasoil fraction;   c) providing the contaminant-containing Fischer-Tropsch gasoil fraction to an absorption zone comprising at least one absorbent material and contacting the contaminant-containing Fischer-Tropsch gasoil fraction with the absorbent material to absorb at least part of contaminant; and   d) retrieving from the absorption zone a purified Fischer-Tropsch gasoil fraction, which purified Fischer-Tropsch gasoil fraction is contaminant-depleted with respect to the contaminant-containing Fischer-Tropsch gasoil fraction.   
     
     
         2 . The process according to  claim 1 , wherein the one or more contaminants are selected from the group consisting of oxygenate compounds and aromatics. 
     
     
         3 . The process according to  claim 1 , wherein at least one absorbent material is a molecular sieve material, preferably zeolite X, zeolite 13X, zeolite Y, dealuminized zeolite Y, ultrastable Y, ZSM-12, mordenite, zeolite beta, zeolite L, zeolite omega. 
     
     
         4 . The process according to  claim 1 , wherein the absorption zone comprises two or more absorbent materials. 
     
     
         5 . The process according to  claim 1 , wherein the contaminant-containing Fischer-Tropsch gasoil fraction is contacted with the absorbent material at a temperature in the range of from 0 to 150° C. 
     
     
         6 . The process according to  claim 1 , wherein the contaminant-containing Fischer-Tropsch gasoil fraction is contacted with the absorbent material in a fixed bed reactor comprising at least one fixed bed of absorbent material. 
     
     
         7 . The process according to  claim 1 , wherein the Fischer-Tropsch-derived gasoil has a final boiling point of no more than 450° C. 
     
     
         8 . A method of using a purified Fischer-Tropsch gasoil fraction obtained in the process of  claim 1  as a solvent, diluent or functional fluid.