Polynuclear compounds derived from an organic solution

Abstract

Polynuclear compounds dissolved and contained within an organic solvent are separated from the organic solvent by rendering the organic compounds insoluble within the organic solvent. Accordingly this invention removes polynuclear compounds from a saturated organic solvent. The polynuclear compounds are derived from black liquor obtained from kraft digestion. Whereby polynuclear compounds, substantially free of an organic solvent, are obtained from the organic solvent.

What is claimed is:  
     
         1 . A method to derive polynuclear compounds dissolved in an organic solvent, which comprises: 
 providing an organic solvent containing dissolved polynuclear compounds, and    separating said polynuclear compounds from said organic solvent, and    recycling the heretofore separated organic solvent, whereby polynuclear compounds substantially free of an organic solvent, are obtained from an organic solvent.    
     
     
         2 . The method as described in  claim 1  wherein said polynuclear compounds are derived from black liquor obtained from kraft digestion.  
     
     
         3 . The method as described in  claim 1  wherein said polynuclear compounds, substantially free of said organic solvent, are subjected to delignification of wood chips within kraft digestion.  
     
     
         4 . The method as described in  claim 1  wherein said polynuclear compounds are selected from the group of anthraquinone, 2-methyl-anthraquinone including an individual or a combination thereof.  
     
     
         5 . The method as described in  claim 1  wherein said organic solvent is selected from the group of hydrocarbons, organic halogens and alcohols including an individual or a combination thereof.  
     
     
         6 . The method as described in  claim 1  wherein said organic solvent containing dissolved polynuclear compounds is subjected to cooling to provide phases of polynuclear compounds and a phase of organic solvent saturated with polynuclear compounds.  
     
     
         7 . The method as described in  claim 6  wherein the phases are subjected to a centrifuge to separate phases by differences in density to obtain organic solvent for recycle, and polynuclear compounds substantially devoid of the organic solvent.  
     
     
         8 . The method as described in  claim 1  wherein said polynuclear compounds are supplied from kraft pulping digestion.  
     
     
         9 . The method as described in  claim 1  wherein said polynuclear compounds are supplied from soda pulping digestion.