Formulating a sealant fluid using gas to liquid base stocks

Abstract

It has been determined that sealant fluid formulations comprising a lubricant oil derived from Fischer-Tropsch waxes demonstrate performance comparable to sealant fluid comprising lubricants derived from polyalphaolefins (PAO's). The sealant fluids of the current invention can provide excellent performance properties similar to those provided by PAO based sealant fluids, but at lower cost.

What is claimed is: 
     
         1 .- 18 . (canceled) 
     
     
         19 . A process for making a sealant fluid, comprising:
 a. selecting a waxy feed having:
 i. greater than 75 wt % n-paraffins; and 
 ii. less than 25 ppm total combined nitrogen and sulfur; 
   b. hydroisomerization dewaxing the waxy feed to produce a lubricant base oil;   c. fractionating the lubricant base oil into one or more fractions;   d. selecting one or more of the fractions having:
 i. an average molecular weight greater than or equal to 320; 
 ii. a viscosity index greater than or equal to 118; 
 iii. a weight percent olefins less than 25; and 
   e. blending the one or more selected fractions with an additive package comprising a thickener to produce a barrier fluid having a VI of at least 120.   
     
     
         20 . The process of  claim 19 , wherein the sealant fluid is a barrier fluid or a buffer fluid.