Process for Dechlorination of Hydrocarbon Streams and Pyrolysis Oils

Abstract

A process for dechlorination of a hydrocarbon stream includes contacting the hydrocarbon stream with a hydroprocessing catalyst in the presence of hydrogen to yield a hydrocarbon product which meets steam cracker requirements for chloride content, and in additional embodiments, requirements for olefin content.

What is claimed is: 
     
         1 . A process for dechlorination of a hydrocarbon stream comprising:
 contacting the hydrocarbon stream with a hydroprocessing catalyst in the presence of hydrogen to yield a hydrocarbon product, wherein the hydrocarbon stream comprises one or more chloride compounds in a concentration of 5 ppm or more based on a total weight of the hydrocarbon stream; and   recovering a treated hydrocarbon stream from the hydrocarbon product, wherein the treated hydrocarbon stream comprises the one or more chloride compounds in a concentration of less than 5 ppm based on a total weight of the treated hydrocarbon stream.   
     
     
         2 . The process of  claim 1 , wherein the treated hydrocarbon stream comprises the one or more chloride compounds in a concentration of less than 1 ppm based on the total weight of the treated hydrocarbon stream. 
     
     
         3 . The process of  claim 1 , wherein the hydrocarbon stream comprises the one or more chloride compounds in a concentration of greater than 200 ppm based on a total weight of the hydrocarbon stream. 
     
     
         4 . The process of  claim 1 , wherein the hydrocarbon stream further comprises one or more olefins, wherein the treated hydrocarbon stream further comprises the one or more olefins in a concentration of less than 1 wt % based on the total weight of the treated hydrocarbon stream. 
     
     
         5 . The process of  claim 4 , wherein the one or more olefins are present in the hydrocarbon stream in a concentration of 20 wt % or more based on the total weight of the hydrocarbon stream. 
     
     
         6 . The process of  claim 1 , wherein the hydrocarbon stream further comprises paraffins. 
     
     
         7 . The process of  claim 6 , wherein the hydrocarbon stream further comprises one or more olefins, wherein the treated hydrocarbon stream further comprises the paraffins and the one or more olefins, wherein the one or more olefins of the treated hydrocarbon stream are present in a concentration of less than 1 wt % based on the total weight of the treated hydrocarbon stream. 
     
     
         8 . The process of  claim 1 , wherein the hydrocarbon stream further comprises one or more sulphides, wherein the one or more sulphides of the hydrocarbon stream are present in an amount such that a sulphur content of the hydrocarbon stream is about 0.5 wt % to about 5 wt % based on the total weight of the hydrocarbon stream. 
     
     
         9 . The process of  claim 1 , wherein the hydroprocessing catalyst comprises cobalt and molybdenum on an alumina support, nickel and molybdenum on an alumina support, or nickel and molybdenum sulphides, wherein contacting the hydrocarbon stream with the hydroprocessing catalyst comprises:
 contacting one or more sulphides contained in or added to the hydrocarbon stream with the hydroprocessing catalyst, and wherein the one or more sulphides are contained in or added to the hydrocarbon stream in an amount such that a sulphur content of the hydrocarbon stream is about 2 wt % based on the total weight of the hydrocarbon stream.   
     
     
         10 . The process of  claim 1 , wherein the step of contacting is performed at a temperature of 100° C. to 450° C. 
     
     
         11 . The process of  claim 1 , wherein the step of contacting is performed at a weight hourly space velocity of 0.1 to 10 hr −1 , at a hydrogen to hydrocarbon ratio of 10 to 3,000 NL/L, and at a pressure of 1 to 200 barg. 
     
     
         12 . The process of  claim 1 , wherein the treated hydrocarbon stream comprises the one or more chloride compounds in a concentration of less than 3 ppm based on a total weight of the treated hydrocarbon, the process further comprising:
 feeding the treated hydrocarbon stream to a steam cracker.   
     
     
         13 . The process of  claim 1 , further comprising:
 blending the treated hydrocarbon stream with a non-chlorinated hydrocarbon stream to yield a blended hydrocarbon stream comprising the one or more chloride compounds in a concentration of less than 3 ppm based on a total weight of the blended hydrocarbon stream; and   feeding the blended hydrocarbon stream to a steam cracker.   
     
     
         14 . The process of  claim 1 , wherein recovering a treated hydrocarbon stream from the hydrocarbon product comprises:
 separating a treated product from a chlorine-containing gas in a separator; and   flowing the treated product in the treated hydrocarbon stream from the separator.   
     
     
         15 . The process of  claim 1 , wherein no hydrogen halides and no halogenated organic compounds are recycled to the hydroprocessing reactor. 
     
     
         16 . The process of  claim 1 , wherein the step of contacting is performed without use of chlorine sorbents. 
     
     
         17 . The process of  claim 1 , wherein the step of contacting is performed without the presence of Na 2 CO 3  in an effective amount to function as a dechlorinating agent. 
     
     
         18 . The process of  claim 1 , wherein the hydroprocessing reactor is configured to operate in the slurry phase. 
     
     
         19 . The process of  claim 1 , wherein the step of contacting includes simultaneous dechlorination and hydrogenation of the hydrocarbon stream such that the treated hydrocarbon stream comprises the one or more chloride compounds in a concentration less than 1 ppm and one or more olefins in a concentration less than 1 wt % based on the total weight of the treated hydrocarbon stream. 
     
     
         20 . The process of  claim 1 , wherein the one or more chloride compounds include 1-chlorohexane, 2-chloropentane, 3-chloro-3-methyl pentane, (2-chloroethyl) benzene, chlorobenzene, or combinations thereof.