Hydrogenation Process

Abstract

A process for the production of a fuel composition comprising hydrocarbons derived from carboxylic acids and/or carboxylic acid esters, which process comprises feeding hydrogen and a hydrocarbon-containing stream to a first reactor to reduce levels of olefins and/or heteroatom-containing compounds in the hydrocarbon-containing stream, and feeding the so-treated hydrocarbon-containing stream to a second reactor together with hydrogen and a carboxylic acid and/or ester to produce a second hydrocarbon-containing stream in which at least some of the hydrocarbons are derived from the carboxylic acid and/or ester.

1 . A process for the production of a fuel composition comprising hydrocarbons derived from carboxylic acids and/or carboxylic acid esters, which process comprises the steps of;
 (a) feeding hydrogen and a first hydrocarbon-containing process stream to a first reactor;   (b) maintaining conditions within the first reactor sufficient to produce a first hydrocarbon-containing product stream with a reduced concentration of heteroatom-containing organic compounds and/or olefins compared to the first hydrocarbon-containing process stream;   (c) removing the first hydrocarbon-containing product stream from the first reactor; characterised by the process additionally comprising the steps of;   (d) feeding hydrogen, a carboxylic acid and/or carboxylic acid ester, and at least a 15 portion of the first hydrocarbon-containing product stream to a second reactor;   (e) maintaining conditions within the second reactor sufficient to convert at least some of the carboxylic acid and/or carboxylic acid ester to one or more hydrocarbons;   (f) removing a second hydrocarbon-containing product stream from the second 20 reactor, in which at least a portion of the hydrocarbons are derived from the carboxylic acid and/or carboxylic acid ester.   
   
   
       2 . A process as claimed in  claim 1 , in which the fuel composition is a diesel fuel. 
   
   
       3 . A process as claimed in  claim 1 , in which carboxylic acid and/or carboxylic acid ester is a fatty acid and/or ester. 
   
   
       4 . A process as claimed in  claim 1 , in which the carboxylic acid and/or carboxylic acid ester is derived from plant or animal fat or oil. 
   
   
       5 . A process as claimed in  claim 1 , in which the first hydrocarbon containing process stream comprises middle distillate hydrocarbons from a crude oil refinery. 
   
   
       6 . A process as claimed in  claim 5 , in which the hydrocarbons comprise both straight-run middle distillate hydrocarbons, and hydrocarbons derived from other refinery process with a similar boiling range to that of the straight-run fraction. 
   
   
       7 . A process as claimed in  claim 1 , in which the first hydrocarbon-containing process stream has a sulphur concentration of 200 ppm or more, expressed as elemental sulphur. 
   
   
       8 . A process as claimed in  claim 1 , in which the first hydrocarbon containing product stream comprises less than 200 ppm sulphur expressed as elemental sulphur. 
   
   
       9 . A process as claimed in  claim 1 , in which the first reactor is maintained at a temperature in the range of from 250 to 430° C. and a pressure in the range of from 20 to 200 bara (2 to 20 MPa). 
   
   
       10 . A process as claimed in  claim 1 , in which the second reactor is maintained at a temperature in the range of from 200 to 410° C. and a pressure in the range of from 20 to 200 bara (2 to 20 MPa). 
   
   
       11 . A process as claimed in  claim 1 , in which additional hydrocarbons are fed to the second reactor.