Oxygenate treatment of dewaxing catalyst for greater yield of dewaxed product

Abstract

Fischer-Tropsch hydrocarbon synthesis using a cobalt catalyst is used to produce waxy fuel and lubricant oil hydrocarbons from synthesis gas derived from natural gas. The waxy hydrocarbons are hydrodewaxed, with reduced conversion to lower boiling hydrocarbons, by contacting the waxy hydrocarbons, in the presence of hydrogen, with an unsulfided 10-ring, 1-dimensional zeolite catalyst that has been reduced and then treated by contacting it with the synthesized hydrocarbons containing one or more oxygenates, including indigenous oxygenate. Tail gas from the hydrodewaxing reactor can be used for the hydrocarbon synthesis.

1 . An unsulfided hydrodewaxing catalyst comprising a Group VIII metal component and a 10-ring, 1-dimensional zeolite component, wherein said catalyst is made by reduction and then treatment with a stream containing one or more oxygenates, and wherein the Group VIII metal is Pt, Pd, or mixtures thereof  
     
     
         2 . A catalyst according to  claim 1  wherein said zeolite component is at least one of ZSM-22, ZSM-23, ZSM-35, ZSM-48, ZSM-57 or rare earth exchanged ferrierite.  
     
     
         3 . A catalyst according to  claim 2  wherein said zeolite component is ZSM-48.  
     
     
         4 . A catalyst according to  claim 3  wherein said oxygenates comprise one or more oxygen containing molecules, preferably one or more functional groups containing hydroxyl, mono and polyhydric alcohols, esters, ethers, ketones, aldehydes, carboxylic acids, and mixtures thereof.  
     
     
         5 . A catalyst according to  claim 4  wherein said one or more oxygenates are present in said stream in an amount of at least 100 wppm, measured as oxygen, preferably at least 200 wppm, measured as oxygen.  
     
     
         6 - 55 . (canceled)