Contaminant removal from hydrocarbon streams with ionic liquids

Abstract

A process for removing sulfur and nitrogen contaminants from a hydrocarbon stream using a Brønsted acid or an ionic liquid and a Brønsted acid is described. The process includes contacting the hydrocarbon stream comprising the contaminant with a Brønsted acid or a hydrocarbon-immiscible ionic liquid and the Brønsted acid to produce a mixture comprising the hydrocarbon and the Brønsted acid comprising at least a portion of the removed contaminant or a hydrocarbon-immiscible ionic liquid comprising at least a portion of the removed contaminant; and separating the mixture to produce a hydrocarbon effluent having a reduced level of the contaminant and a Brønsted acid effluent comprising the Brønsted acid comprising at least the portion of the removed contaminant or a hydrocarbon-immiscible ionic liquid effluent comprising the hydrocarbon-immiscible ionic liquid comprising at least the portion of the removed contaminant.

What is claimed is: 
     
         1 . A process for removing a contaminant comprising at least one of sulfur and nitrogen from a hydrocarbon stream comprising:
 contacting the hydrocarbon stream comprising the contaminant with a Brønsted acid, or a hydrocarbon-immiscible ionic liquid and a Brønsted acid under contacting conditions so that the Brønsted acid, or the hydrocarbon-immiscible ionic liquid and the Brønsted acid are in a liquid state to produce a mixture comprising the hydrocarbon and the Brønsted acid comprising at least a portion of the removed contaminant or a hydrocarbon-immiscible ionic liquid comprising at least a portion of the removed contaminant; and   separating the mixture to produce a hydrocarbon effluent having a reduced level of the contaminant and a Brønsted acid effluent comprising the Brønsted acid comprising at least the portion of the removed contaminant or a hydrocarbon-immiscible ionic liquid effluent comprising the hydrocarbon-immiscible ionic liquid comprising at least the portion of the removed contaminant.   
     
     
         2 . The process of  claim 1  wherein the hydrocarbon-immiscible ionic liquid comprises at least one of nitrogen containing ionic liquids and phosphorus containing ionic liquids. 
     
     
         3 . The process of  claim 1  wherein the Brønsted acid comprises sulfonic acid, derivatives of sulfonic acid, sulfuric acid, phosphoric acid, derivatives of phosphoric acid, phosphonic acid, derivatives of phosphonic acid, hydrochloric acid, hydrobromic acid, nitric acid, sulfurous acid, carboxylic acids having from 1 to 8 carbons, and combinations thereof. 
     
     
         4 . The process of  claim 1  wherein a ratio of the Brønsted acid to the hydrocarbon-immiscible ionic liquid is in a range of about to about 0.01:1 to about 0.5:1. 
     
     
         5 . The process of  claim 1  wherein the hydrocarbon stream has a boiling point in a range of about 30° C. to about 525° C. 
     
     
         6 . The process of  claim 1  wherein the contacting step is conducted at a temperature in a range of about 20° C. to about 150° C., and a pressure in a range of about 100 kPa (g) to about 3 MPa(g). 
     
     
         7 . The process of  claim 1  further comprising passing at least a portion of the hydrocarbon effluent to a hydrocarbon conversion process. 
     
     
         8 . The process of  claim 1  further comprising:
 regenerating the hydrocarbon-immiscible ionic liquid effluent; and 
 recycling the regenerated hydrocarbon-immiscible based ionic liquid effluent to the contacting step. 
 
     
     
         9 . The process of  claim 1  wherein a ratio of the hydrocarbon to the hydrocarbon-immiscible ionic liquid is in a range of about 1:1,000 to about 1,000:1. 
     
     
         10 . The process of  claim 1  further comprising contacting the hydrocarbon-immiscible ionic liquid effluent with a regeneration solvent to form an extract stream comprising the contaminant and a stream of regenerated hydrocarbon-immiscible ionic liquid. 
     
     
         11 . The process of  claim 10  wherein the regeneration solvent comprises water, naphtha, gasoline, diesel, light cycle oil, light coker gas oil, alcohols, aldehydes, ketones, ether, and combinations thereof. 
     
     
         12 . The process of  claim 10  further comprising separating the stream of regenerated hydrocarbon-immiscible ionic liquid from the regeneration solvent. 
     
     
         13 . The process of  claim 12  further comprising recycling the stream of regenerated hydrocarbon-immiscible ionic liquid to the contacting step. 
     
     
         14 . The process of  claim 1  wherein the ionic liquid comprises an imidazolium ionic liquid, an ammonium ionic liquid, a pyridinium ionic liquid, a phosphonium ionic liquid, a lactamium ionic liquid, a pyrrolidinium ionic liquid, or combinations thereof. 
     
     
         15 . The process of  claim 1  wherein the hydrocarbon effluent contains less than 25 ppm hydrocarbon-immiscible ionic liquid. 
     
     
         16 . A process for removing a contaminant comprising at least one of sulfur and nitrogen from a hydrocarbon stream comprising:
 contacting the hydrocarbon stream comprising the contaminant with a hydrocarbon-immiscible ionic liquid and a Brønsted acid under contacting conditions so that the hydrocarbon-immiscible ionic liquid and the Brønsted acid are in a liquid state to produce a mixture comprising the hydrocarbon and a hydrocarbon-immiscible ionic liquid comprising at least a portion of the removed contaminant, wherein the hydrocarbon stream has a boiling point in a range of about 30° C. to about 525° C., wherein the hydrocarbon-immiscible ionic liquid comprises an imidazolium ionic liquid, an ammonium ionic liquid, a pyridinium ionic liquid, a phosphonium ionic liquid, a lactamium ionic liquid, a pyrrolidinium ionic liquid, or combinations thereof, and wherein the Brønsted acid comprises sulfonic acid, derivatives of sulfonic acid, sulfuric acid, phosphoric acid, derivatives of phosphoric acid, phosphonic acids, derivatives of phosphonic acid, hydrochloric acid, hydrobromic acid, nitric acid, sulfurous acid, carboxylic acids having from 1 to 8 carbons, and combinations thereof, and wherein a ratio of the Brønsted acid to the hydrocarbon-immiscible ionic liquid is in a range of about to about 0.01:1 to about 0.5:1; and   separating the mixture to produce a hydrocarbon effluent having a reduced level of the contaminant and a hydrocarbon-immiscible ionic liquid effluent comprising the hydrocarbon-immiscible ionic liquid comprising at least the portion of the removed contaminant, wherein the hydrocarbon effluent contains less than 25 ppm hydrocarbon-immiscible ionic liquid.   
     
     
         17 . The process of  claim 16  wherein the contacting step is conducted at a temperature in a range of about 20° C. to about 150° C. 
     
     
         18 . The process of  claim 18  further comprising:
 regenerating the hydrocarbon-immiscible ionic liquid effluent; and 
 recycling the regenerated hydrocarbon-immiscible based ionic liquid effluent to the contacting step. 
 
     
     
         19 . The process of  claim 1  wherein the hydrocarbon-immiscible ionic liquid effluent is regenerated by contacting the hydrocarbon-immiscible ionic liquid effluent with a regeneration solvent to form an extract stream comprising the contaminant and a stream of regenerated hydrocarbon-immiscible ionic liquid, and further comprising:
 separating the stream of regenerated hydrocarbon-immiscible ionic liquid from the regeneration solvent. 
 
     
     
         20 . The process of  claim 19  wherein the regeneration solvent comprises water, naphtha, gasoline, diesel, light cycle oil, light coker gas oil, alcohols, aldehydes, ketones, ether, and combinations thereof.