Separation of selected asphaltenes from a hydrocarbon-containing feedstock

Abstract

Toluene-insoluble hydrocarbon-containing compounds are selectively separated from a hydrocarbon-containing feedstock containing at least 5 wt. % n-heptane insoluble hydrocarbon-containing materials, wherein at least 10 wt. % of the n-heptane insoluble hydrocarbon-containing materials are toluene insoluble hydrocarbon-containing materials, by contacting the hydrocarbon-containing feedstock with a porous silica adsorbent having a median pore size diameter of less than 180 Å at a temperature of from 120° C. to 300° C.

What is claimed is: 
     
         1 . A process for separating toluene insoluble compounds from a hydrocarbon-containing feedstock, comprising:
 providing a hydrocarbon-containing feedstock comprising at least 5 wt. % n-heptane insoluble hydrocarbon-containing materials, wherein at least 10 wt. % of the n-heptane insoluble hydrocarbon-containing materials are toluene insoluble hydrocarbon-containing materials, and wherein n-heptane insoluble hydrocarbon-containing materials are hydrocarbon-containing materials that precipitate from a liquid hydrocarbon-containing material in a 40:1 volume mixture of n-heptane:liquid hydrocarbon material at 25° C. and toluene insoluble hydrocarbon-containing materials are materials that precipitate from a liquid hydrocarbon-containing material in a 40:1 volume mixture of toluene:liquid hydrocarbon material at 25° C.;   contacting the hydrocarbon-containing feedstock with a porous silica adsorbent at a temperature of from 120° C. to 300° C., wherein the silica of the silica adsorbent has a pore size distribution having a median pore size diameter of less than 180 Å as determined by mercury porosimetry;   separating a hydrocarbon-containing product from the silica adsorbent, wherein the hydrocarbon-containing product contains at most 50% of the toluene-insoluble hydrocarbon-containing compounds of the hydrocarbon-containing feedstock.   
     
     
         2 . The process of  claim 1  wherein the hydrocarbon-containing product contains at least 50% less, or at least 70% less, or at least 80% less of the toluene insoluble compounds of the n-heptane insoluble compounds relative to the hydrocarbon-containing feedstock. 
     
     
         3 . The process of  claim 1  wherein the silica adsorbent is a silica gel that has not been heated to a temperature of at least 500° C. 
     
     
         4 . The process of  claim 1  wherein the pore size distribution of the silica of the silica adsorbent has a median pore size diameter of from 50 Å to 150 Å. 
     
     
         5 . The process of  claim 1  wherein the silica of the silica adsorbent has a surface area of at least 100 m 2 /g. 
     
     
         6 . The process of  claim 1  wherein the silica adsorbent has a moisture content of from 2 wt. % to 5 wt. % water. 
     
     
         7 . The process of  claim 1  wherein the hydrocarbon-containing feedstock and the silica adsorbent are contacted at a temperature of from 150° C. to 250° C. 
     
     
         8 . The process of  claim 1  further comprising the steps of:
 contacting the silica adsorbent with a solvent effective to solvate the toluene insoluble compounds after separating the hydrocarbon-containing product from the silica adsorbent; and 
 separating the solvent and at least a portion of the toluene insoluble compounds from the silica adsorbent. 
 
     
     
         9 . The process of  claim 8  wherein the solvent is selected from the group consisting of pyridine, n-pyrrolidone, dichloromethane, methanol, and a mixtures thereof. 
     
     
         10 . The process of  claim 1  further comprising cracking the separated hydrocarbon-containing product. 
     
     
         11 . The process of  claim 1  further comprising the step of blending the separated hydrocarbon-containing product with a hydrocarbon-containing liquid. 
     
     
         12 . The process of  claim 11  wherein the hydrocarbon-containing liquid with which the separated hydrocarbon-containing product is blended is comprised of at least 10 wt. % n-heptane insoluble compounds. 
     
     
         13 . The process of  claim 1  wherein the contacting temperature and time are controlled such that the hydrocarbon-containing product has a dynamic viscosity at 25° C. that is at most 50% of the dynamic viscosity of the hydrocarbon-containing feed at 25° C.