Compressor Lubricant Compositions and Preparation Thereof

Abstract

A compressor lubricant composition providing energy savings and exhibiting excellent oxidation stability is provided. The composition comprises (i) 80 to 99.999 weight percent of an isomerized base oil; and (ii) 0.001-20 weight percent of at least an additive selected from an additive package, oxidation inhibitors, pour point depressants, metal deactivators, metal passivators, anti-foaming agents, friction modifiers, anti-wear agents, and mixtures thereof; wherein the isomerized base oil has consecutive numbers of carbon atoms, less than 0.05 wt. % aromatics, a ratio of molecules with monocycloparaffinic functionality to molecules with multicyloparaffinic functionality greater than 2. In one embodiment, compressors employing the lubricant composition with isomerized base oil consumes at least 1% less power than compressors employing the lubricant compositions of the prior art.

1 . A compressor lubricant composition, comprising: (i) 80 to 99.999 weight percent of an isomerized base oil; and (ii) 0.001-20 weight percent of at least an additive selected from an additive package, oxidation inhibitors, pour point depressants, metal deactivators, metal passivators, anti-foaming agents, friction modifiers, anti-wear agents, and mixtures thereof; wherein
 the isomerized base oil has consecutive numbers of carbon atoms, less than 0.05 wt. % aromatics, a ratio of molecules with monocycloparaffinic functionality to molecules with multicyloparaffinic functionality greater than 2, and   wherein the weight percents of (i) and (ii) are relative to the total weight of the composition.   
     
     
         2 . The compressor lubricant composition of  claim 1 , wherein a compressor that employs the composition consumes at least 2% less power than a compressor employing a lubricant composition without the isomerized base oil. 
     
     
         3 . The compressor lubricant composition of  claim 1 , wherein a compressor that employs the composition consumes at least 5% less power than a compressor employing a lubricant composition without the isomerized base oil. 
     
     
         4 . The compressor lubricant composition of  claim 1 , wherein a compressor that employs the composition consumes at least 10% less power than a compressor employing a lubricant composition without the isomerized base oil. 
     
     
         5 . The compressor lubricant composition of  claim 1 , wherein the isomerized base oil has a viscosity index (VI) of at least 140. 
     
     
         6 . The compressor lubricant composition of  claim 1 , wherein the isomerized base oil has a VI of at least 160. 
     
     
         7 . The compressor lubricant composition of  claim 1 , wherein the isomerized base oil has a flash point of at least 250° C. 
     
     
         8 . The compressor lubricant composition of  claim 1 , wherein the composition has a RPVOT as measured according to ASTM D2272-02 of greater than 600 minutes. 
     
     
         9 . The compressor lubricant composition of  claim 8 , wherein the composition has a RPVOT as measured according to ASTM D2272-02 of greater than 1000 minutes. 
     
     
         10 . The compressor lubricant composition of  claim 1 , wherein the composition meets at least one of German standard DIN 51 506 class VDL, ISO/DP 6521-L-DAB and ISO 6743-3A-DAC. 
     
     
         11 . The compressor lubricant composition of  claim 1 , wherein the composition has an evaporation loss of less than 1% per MIP-48 Oxidation Test (24 hrs.). 
     
     
         12 . The compressor lubricant composition of  claim 1 , wherein the composition has an evaporation loss of less than 0.75% per MIP-48 Oxidation Test (24 hrs.). 
     
     
         13 . The compressor lubricant composition of  claim 1 , wherein the composition has a RPVOT of greater than 300 minutes according to ASTM D2272-02. 
     
     
         14 . The compressor lubricant composition of  claim 1 , wherein the composition has a RPVOT of greater than 600 minutes according to ASTM D2272-02. 
     
     
         15 . The compressor lubricant composition of  claim 1 , wherein the composition separates from water in less than 60 minutes as measured according to ASTM D-1401-2002. 
     
     
         16 . The compressor lubricant composition of  claim 1 , further comprising 5 to 20 weight percent based on the total weight of the composition, at least a lubricant base oil selected from vegetable oils and Group I, II, III, IV, and V lubricant base oils as defined in the API Interchange Guidelines, and mixtures thereof. 
     
     
         17 . The compressor lubricant composition of  claim 1 , wherein the isomerized base oil has an auto-ignition temperature of at least 360° C. 
     
     
         18 . The compressor lubricant composition of  claim 1 , wherein the isomerized base oil is a Fischer-Tropsch base oil. 
     
     
         19 . The compressor lubricant composition of  claim 1 , wherein the composition comprises at least isomerized base oil having a kinematic viscosity at 100° C. between 6.5 and 16 mm 2 /s and a kinematic viscosity at 40° C. between 25 mm 2 /s and 120 mm 2 /s. 
     
     
         20 . The compressor lubricant composition of  claim 1 , wherein the isomerized base oil has an Oxidator BN of 15 to 50 hours; and a Noack volatility in wt. % of 0.5 to 5 as measured by ASTM D5800-05 Procedure B. 
     
     
         21 . The compressor lubricant composition of  claim 1 , wherein the isomerized base oil has a pour point in the range of −10 and −30° C. 
     
     
         22 . The compressor lubricant composition of  claim 1 , wherein the isomerized base oil is a Fischer-Tropsch base oil having less than 0.05 wt. % aromatics and a molecular weight of 500 to 800 by ASTM D 2503-92 (Reapproved 2002). 
     
     
         23 . A method for operating a compressor, the method comprising using a compressor lubricant composition comprising: (i) 80 to 99.999 weight percent of an isomerized base oil; and (ii) 0.001-20 weight percent of at least an additive selected from an additive package, oxidation inhibitors, pour point depressants, metal deactivators, metal passivators, anti-foaming agents, friction modifiers, anti-wear agents, and mixtures thereof; wherein the isomerized base oil has consecutive numbers of carbon atoms, less than 0.05 wt. % aromatics, a ratio of molecules with monocycloparaffinic functionality to molecules with multicyloparaffinic functionality greater than 2, and wherein the weight percents of (i) and (ii) are relative to the total weight of the composition;
 wherein the compressor lubricant composition consumes at least 2% less power than the compressor employing a lubricant composition without the isomerized base oil.   
     
     
         24 . The method of  claim 23 , wherein the compressor using the composition comprising: (i) 80 to 99.999 weight percent of an isomerized base oil consumes at least 5% less power than the compressor employing a lubricant composition without the isomerized base oil. 
     
     
         25 . The method of  claim 23 , wherein the compressor using the composition comprising: (i) 80 to 99.999 weight percent of an isomerized base oil consumes at least 10% less power than the compressor employing a lubricant composition without the isomerized base oil.