Decomposition of organic chloride in alkylate using metals and alloys

Abstract

Processes for decomposing organic chloride in a hydrocarbon stream may comprise contacting a hydrocarbon stream with a dechlorination element in a dechlorination zone under dechlorination conditions to provide a dechlorinated hydrocarbon product, wherein the dechlorination element may comprise a metal or metal alloy having a high surface area configuration. Such a dechlorination element may be disposed within one or more distillation columns and/or within a separate dechlorination vessel.

What is claimed is: 
     
         1 . A dechlorination process, comprising:
 a) providing a hydrocarbon stream comprising an alkylate product in combination with an organic chloride contaminant; and   b) contacting the hydrocarbon stream under dechlorination conditions in a dechlorination zone with a dechlorination element having a surface area per unit volume in the range from 250 to 1000 m 2 ·m −3  to decompose the organic chloride and to provide a dechlorinated alkylate product, wherein the dechlorination element has a metal surface comprising a metal alloy.   
     
     
         2 . The process according to  claim 1 , wherein the dechlorination element comprises from 90 to 100 wt % of the metal alloy. 
     
     
         3 . The process according to  claim 1 , wherein:
 the metal surface of the dechlorination element is of uniform composition, and   the metal alloy is selected from the group consisting of an Fe based alloy, a Ni based alloy, and a Cu based alloy.   
     
     
         4 . The process according to  claim 1 , wherein the metal alloy comprises at least 90 wt % Fe, and an alloying element selected from the group consisting of Al, B, C, Co, Cr, Cu, Mg, Mn, Mo, N, Ni, Nb, Pb, S, Si, Ta, Ti, V, W, Zr, and combinations thereof. 
     
     
         5 . The process according to  claim 1 , wherein the metal surface of the dechlorination element consists essentially of the metal alloy. 
     
     
         6 . The process according to  claim 5 , wherein the metal alloy comprises carbon steel. 
     
     
         7 . The process according to  claim 1 , wherein the dechlorination element is configured as at least one metal sheet. 
     
     
         8 . The process according to  claim 7 , wherein said metal sheet has a configuration selected from the group consisting of folded, ridged, grooved, corrugated, perforated, embossed, and combinations thereof. 
     
     
         9 . The process according to  claim 1 , wherein the dechlorination element is disposed within a distillation column. 
     
     
         10 . The process according to  claim 9 , wherein step a) comprises:
 I) contacting an isoparaffin and an olefin with an ionic liquid catalyst in an ionic liquid alkylation zone under ionic liquid alkylation conditions, and   II) separating the hydrocarbon stream from an effluent of the ionic liquid alkylation zone, and wherein the distillation column comprises at least one of an isostripper and a debutanizer.   
     
     
         11 . The process according to  claim 1 , wherein:
 the hydrocarbon stream comprises a fraction from a distillation column, and   the dechlorination element is disposed in a dechlorination vessel external to the distillation column.   
     
     
         12 . The process according to  claim 1 , wherein:
 step b) comprises contacting the hydrocarbon stream with the dechlorination element in the substantial absence of H 2  gas, and   the decomposition of the organic chloride generates HCl.   
     
     
         13 . A dechlorination process, comprising:
 a) providing a hydrocarbon stream comprising an alkylate product in combination with an alkyl chloride contaminant; and   b) contacting the hydrocarbon stream under dechlorination conditions in a dechlorination zone, in the substantial absence of H 2  gas, with a dechlorination element comprising from 90 to 100 wt % of a metal alloy to decompose the alkyl chloride and to provide a dechlorinated alkylate product, wherein:   the dechlorination element has a metal surface of uniform composition comprising the metal alloy,   the dechlorination element has a surface area per unit volume in the range from 250 to 1000 m 2 ·m −3 , and   the metal alloy comprises from 95 to 100 wt % of an elemental metal selected from the group consisting of Al, Co, Cr, Cu, Fe, Mg, Mn, Mo, Nb, Ni, Pb, Ta, Ti, V, W, Zr, and combinations thereof.   
     
     
         14 . The process according to  claim 13 , wherein:
 the dechlorination element is disposed within a distillation column,   the dechlorination element is confined to the lower half (½) of the distillation column, and   the distillation column comprises at least one of an isostripper and a debutanizer.   
     
     
         15 . The process according to  claim 13 , wherein:
 the hydrocarbon stream comprises a bottoms fraction from a distillation column, and   the dechlorination element is housed in a dechlorination vessel external to the distillation column.   
     
     
         16 . The process according to  claim 13 , wherein:
 the dechlorination element consists essentially of the metal alloy, and   the metal alloy is selected from the group consisting of an Fe based alloy, a Ni based alloy, and a Cu based alloy.   
     
     
         17 . A dechlorination process, comprising:
 a) contacting an isoparaffin and an olefin with an ionic liquid catalyst in an ionic liquid alkylation zone under ionic liquid alkylation conditions;   b) separating a hydrocarbon stream from an effluent of the ionic liquid alkylation zone, wherein the hydrocarbon stream comprises an alkylate product in combination with an alkyl chloride contaminant;   c) feeding the hydrocarbon stream to a distillation column having a dechlorination element disposed therein; and   d) contacting the hydrocarbon stream with the dechlorination element under dechlorination conditions in a dechlorination zone within the distillation column to decompose the alkyl chloride so as to generate HCl and to provide a dechlorinated alkylate product, wherein:   the dechlorination element has a metal surface of uniform composition comprising from 95 to 100 wt % of an elemental metal selected from the group consisting of Al, Co, Cr, Cu, Fe, Mg, Mn, Mo, Nb, Ni, Pb, Ta, Ti, V, W, Zr, and combinations thereof, and   the dechlorination element has a surface area per unit volume in the range from 250 to 1000 m 2 ·m −3 .   
     
     
         18 . The process according to  claim 17 , wherein:
 the dechlorination element is confined to the lower half (½) of the distillation column, and   the dechlorination element occupies at least 50% of the cross-sectional area of the distillation column.   
     
     
         19 . The process according to  claim 18 , wherein:
 the metal surface of the dechlorination element comprises a ferrous alloy, and   the dechlorination element occupies at least 80% of the cross-sectional area of the distillation column.   
     
     
         20 . The process according to  claim 19 , wherein the distillation column comprises at least one of an isostripper and a debutanizer.