Hydrotreating supercritical solvent extracts in the presence of alkane extractants

Abstract

A process of recovering the hydrocarbon values from low organic carbon content deposits comprises the hydrotreating of hydrocarbons from those deposits in the presence of supercritical alkane-containing solvent.

I claim: 
     
       1. A process for recovering hydrocarbons from naturally-occurring low organic carbon content carbonaceous material selected from oil shale, tar sand, and mixtures thereof comprising the step of contacting said material under supercritical conditions with an added mixture of structurally analogous hydrocarbon solvents wherein at least one solvent is aromatic, at least one solvent is cycloaliphatic and is structurally analogous to the aromatic solvent, and wherein the cycloaliphatic solvent is present in an amount of 2-10% by weight based on the total solvent weight. 
     
     
       2. The process of claim 1 wherein the cycloaliphatic solvent is present in an amount of 5 to 10% by weight based on the total solvent weight. 
     
     
       3. The process of claims 1 or 2 wherein the aromatic solvent is toluene or benzene and the structurally analogous cycloaliphatic solvent is methylcyclohexane or cyclohexane. 
     
     
       4. The process of claims 1 or 2 further comprising the steps of hydrotreating the material in the presence of the solvent mixture and recovering the resultant hydrotreated product. 
     
     
       5. The process of claim 4 wherein the solvent mixture comprises toluene and methylcyclohexane. .Iadd.6. A process for recovering hydrocarbons from naturally-occurring low organic carbon content carbonaceous materials selected from oil shale, tar sand, and mixtures thereof comprising: (a) subjecting the material to solvent extraction with an alkane-containing solvent under supercritical conditions for the solvent,   (b) then hydrotreating the extract from step (a) with added hydrogen in the presence of the solvent, and   (c) recovering the resultant hydrotreated product. .Iaddend. .Iadd.7. The process of claim 6 wherein the solvent used is n-heptane. .Iaddend. .Iadd.8. The process of claim 6 wherein the solvent employed in step (a) contains a mixture of at least one alkane and at least one aromatic compound. .Iaddend. .Iadd.9. The process of claim 6 wherein the   
     
     
        carbonaceous material is oil shale. .Iaddend. .Iadd.10.  The process of claim 9 wherein the solvent used in step (a) is selected from the group consisting of: n-heptane and a mixture of toluene with methylcyclohexane. .Iaddend.