Process to prepare paraffin wax

Abstract

The present invention provides a paraffin wax having a congealing point according to ASTM D938 of at least 75° C. and a Saybolt colour according to ASTM D156 of at least 25 cm.

1 . A paraffin wax having a congealing point according to ASTM D938 of at least 75° C. and a Saybolt colour according to ASTM D156 of at least 25 cm. 
     
     
         2 . A paraffin wax according to  claim 1 , having a congealing point according to ASTM D938 in the range of from 75 to 85° C. 
     
     
         3 . A paraffin wax according to  claim 1 , having a congealing point according to ASTM D938 of at least 80° C. 
     
     
         4 . A paraffin wax according to  claim 1 , having a Saybolt colour according to ASTM D156 of at least 30 cm. 
     
     
         5 . A paraffin wax according to  claim 1 , having an oil content according to ASTM D721 of less than 0.5 wt. %. 
     
     
         6 . A paraffin wax according to  claim 1 , wherein the paraffin wax is a Fischer-Tropsch derived paraffin wax. 
     
     
         7 . A process to prepare a Fischer-Tropsch derived paraffin wax, the process at least comprising the following steps:
 (a) providing a Fischer-Tropsch product stream comprising paraffins having from 10 to 300 carbon atoms;   (b) separating the Fischer-Tropsch product stream of step (a), thereby obtaining at least a fraction comprising 10 to 17 carbon atoms and a fraction comprising 18 to 300 carbon atoms;   (c) subjecting the fraction comprising 18 to 300 carbon atoms of step (b) to a hydrogenation step, thereby obtaining a hydrogenated fraction comprising 18 to 300 carbon atoms;   (d) separating the hydrogenated fraction comprising 18 to 300 carbon atoms of step (c), thereby obtaining one or more first light waxes having a congealing point in the range of 30 to 75° C. and a second heavy wax having a congealing point according to ASTM D938 in the range of 75 to 120° C.;   (e) separating the heavy wax of step (d) to obtain a distillate wax fraction having a congealing point of at least 75° C.;   (f) hydrofinishing the distillate wax fraction of step (e) thereby obtaining a hydrofinished wax fraction having a congealing point according to ASTM D938 of at least 75° C. and a Saybolt colour according to ASTM D156 of at least 25 cm.   
     
     
         8 . A process according to  claim 7 , wherein the heavy wax of step is separated in step (e) by short path distillation at a pressure between 0.05 mbar and 0.5 mbar. 
     
     
         9 . A process according to  claim 7 , wherein the heavy wax of step is separated in step (e) by short path distillation at a pressure between 0.1 and 0.3 mbar. 
     
     
         10 . A process according to  claim 7 , wherein the hydrofinished wax fraction has a congealing point according to ASTM D938 in the range of from 75 to 85° C. 
     
     
         11 . A process according to  claim 7 , wherein the hydrofinished wax fraction has a congealing point according to ASTM D938 of at least 80° C. 
     
     
         12 . A process according to  claim 7 , wherein the hydrofinished wax fraction has a Saybolt colour according to ASTM D156 of at least 30 cm. 
     
     
         13 . A process according to  claim 7 , wherein the hydrofinished wax fraction has an oil content according to ASTM D721 of less than 0.5 wt. %. 
     
     
         14 . A process according to  claim 7 , wherein the hydrofinished wax fraction has an oil content according to ASTM D721 of less than 0.45 wt. %. 
     
     
         15 . A paraffin wax according to  claim 1 , having an oil content according to ASTM D721 of less than 0.45 wt. %.