Processing of stabilised compositions comprising olefins

Abstract

A composition stabilized against premature polymerization contains a) a hydrocarbon stream having a diene value of at least 0.5 g I2/100 g as measured according to UOP 326, a bromine number of at least 5 g Br2/100 g as measured according to ASTM D1159, and containing at least 2 wt % of plastic liquefaction oil which contains contaminants, wherein said contaminants include constituents which are not boiling below 700° C., preferably not below 600° C., such as gums in the form of plastic oligomers and residues of liquefaction of plastic, optionally metals and optionally solids, the remaining part of said hydrocarbon stream being a diluent, b) at least one additive capable to reduce gums formation or buildup, c) optionally at least one additive which is a dispersant agent, d) optionally at least one other additive which is a metal passivator and/or a metal chelating agent.

1 .- 15 . (canceled) 
     
     
         16 . Composition stabilized against premature polymerization comprising:
 a) a hydrocarbon stream having a diene value of at least 0.5 g I 2 /100 g as measured according to UOP 326, a bromine number of at least 5 g Br 2 /100 g as measured according to ASTM D1159, and containing at least 1 wt % of plastic liquefied oil which is containing contaminants, wherein said contaminants comprise constituents which are not boiling below 700° C., preferably not below 600° C., such as gums in the form of plastic oligomers and residues of liquefaction of plastic, optionally metals and optionally solids, the remaining part of said hydrocarbon stream being a diluent,   b) at least one additive capable to reduce gums formation or buildup selected from hindered phenols including metal salts thereof and c) at least one additive which is a dispersant agent selected from alkylbenzene sulfonates in which the alkyl group contains 8-18 carbons, metal sulfonates and alkenyl succinimides,   d) optionally at least one other additive which is a metal passivator and/or a metal chelating agent.   
     
     
         17 . Composition according to  claim 16 , wherein the additive capable to reduce gums formation or buildup is a hindered phenol and the dispersant agent is a polyisobutylene succinimide. 
     
     
         18 . Composition according to  claim 17 , wherein the additive capable to reduce gums formation or buildup is selected from 4-tert butylcatechol, 2,6-di tertbutylphenol and butylated hydroxyltoluene and the at least one dispersant agent is a polyisobutylene succinimide, in particular of CAS n° 84605-20-9. 
     
     
         19 . Composition stabilized against premature polymerization consisting of:
 a) a hydrocarbon stream having a diene value of at least 0.5 g I 2 /100 g as measured according to UOP 326, a bromine number of at least 5 g Br 2 /100 g as measured according to ASTM D1159, and containing at least 1 wt % of plastic liquefied oil which is containing contaminants, wherein said contaminants comprise constituents which are not boiling below 700° C., preferably not below 600° C., such as gums in the form of plastic oligomers and residues of liquefaction of plastic, optionally metals and optionally solids, the remaining part of said hydrocarbon stream being a diluent,   b) at least one additive capable to reduce gums formation or buildup which is the product of tall oil fatty acids reacted with a polyamine, and optionally c) at least one additive which is a dispersant agent,   d) optionally at least one other additive which is a metal passivator and/or a metal chelating agent.   
     
     
         20 . Composition according to  claim 19 , wherein the additive capable to reduce gums formation or buildup is the product of tall oil fatty acids reacted with a polyalkylene polyamine, optionally selected from diethylenetriamine, triethylenetetramine, or tetraethylenepentamine. 
     
     
         21 . Composition according to  claim 16 , wherein the proportion of b) with reference to a) is from 20 to 5000 wppm, preferably from 50 to 3000 wppm, more preferably from 100 to 1500 wppm. 
     
     
         22 . Composition according to  claim 16 , wherein the proportion of c) with reference to a) is from 20 to 5000 wppm, preferably from 50 to 3000 wppm, more preferably from 100 to 1500 wppm. 
     
     
         23 . Process for preparing a composition stabilized against premature polymerization, comprising:
 (a) providing a hydrocarbon stream having a diene value of at least 0.5 g I 2 /100 g as measured according to UOP 326, a bromine number of at least 5 g Br 2 /100 g as measured according to ASTM D1159, and containing at least 1 wt % of plastic liquefaction oil which is containing contaminants, wherein said contaminants comprise constituents which are not boiling below 700° C., preferably not below 600° C., such as gums in the form of plastic oligomers and residues of liquefaction of plastic, optionally metals and optionally solids, the remaining part of said hydrocarbon stream being a diluent,   (b) adding to the hydrocarbon stream provided in step (a) at least one additive capable to reduce gums formation or buildup selected from hindered phenols including metal salts thereof and (c) adding at least one additive which is a dispersant agent selected from alkylbenzene sulfonates in which the alkyl group contains 8-18 carbons, metal sulfonates and alkenyl succinimides,   (d) optionally adding to the hydrocarbon stream provided in step (a) at least one other additive which is a metal passivator and/or a metal chelating agent.   
     
     
         24 . Process for preparing a composition stabilized against premature polymerization, consisting of:
 (a) providing a hydrocarbon stream having a diene value of at least 0.5 g I 2 /100 g as measured according to UOP 326, a bromine number of at least 5 g Br 2 /100 g as measured according to ASTM D1159, and containing at least 1 wt % of plastic liquefaction oil which is containing contaminants, wherein said contaminants comprise constituents which are not boiling below 700° C., preferably not below 600° C., such as gums in the form of plastic oligomers and residues of liquefaction of plastic, optionally metals and optionally solids, the remaining part of said hydrocarbon stream being a diluent,   (b) adding to the hydrocarbon stream provided in step (a) at least one additive capable to reduce gums formation or buildup which is the product of tall oil fatty acids reacted with a polyamine, and optionally (c) adding to the hydrocarbon stream provided in step (a) at least one additive which is a dispersant agent,   (d) optionally adding to the hydrocarbon stream provided in step (a) at least one other additive which is a metal passivator and/or a metal chelating agent.   
     
     
         25 . Process according to  claim 23 , wherein step (a) comprises:
 (i) providing at least one plastic liquefaction oil by liquefaction of plastic waste,   (ii) optionally providing a diluent,   (iii) preparing a hydrocarbon stream having a diene value of at least 0.5 g I 2 /100 g as measured according to UOP 326, a bromine number of at least 5 g Br 2 /100 g as measured according to ASTM D1159 by mixing said at least one plastic liquefaction oil provided in step (i) with the diluent provided in step (ii) when present, said composition comprising at least 1 wt % of plastic liquefaction oil, the remaining part of said hydrocarbon stream being a diluent.   
     
     
         26 . Process according to  claim 25 , wherein in step (b), said at least one additive capable to reduce gums formation or buildup is added to said at least one plastic liquefaction oil provided by step (i), prior to step (iii). 
     
     
         27 . Process according to  claim 25 , wherein in step (c), said at least one additive is added to said at least one plastic liquefaction oil provided by step (i), prior to step (iii). 
     
     
         28 . Process for the processing of a composition stabilized against premature polymerization, comprising:
 (a) providing a composition stabilized against premature polymerization as claimed in  claim 16 ,   (b) optionally submitting the composition provided in step (a) to an evaporation step under operating conditions efficient to obtain a composition containing a reduced amount of additives,   (c) the stabilized composition provided in step (a) or the composition containing a reduced amount of additives provided in step (b) is (i) processed in a steamcracker, (ii) processed in a fluid catalytic cracker, (iii) processed in a hydroprocessing unit, (iv) processed in an isomerisation unit and/or (v) separated into usable streams for the preparation of fuels such as LPG, naphtha, gas oil, heavy fuel oil and/or for the preparation of lubricants.   
     
     
         29 . The process according to  claim 28 , wherein the stabilized composition provided in step (a) or the composition containing a reduced amount of additives provided in step (b) is, prior to step (c), mixed with naphtha, gasoil or any crude oil refining product to have a liquefied plastic oil concentration ranging from 0.01 wt % to at most 90 wt %; preferably 0.1 wt % to 75 wt % even more preferably 1 wt % to 50 wt %. 
     
     
         30 . The process according to  claim 28 , comprising one of the following features:
 prior to step (b) or prior to step (c), the stabilized composition provided in step (a) is submitted to a purification step to trap silicon and/or metals and/or phosphorous and/or halogenates over at least one trap to obtain a purified stabilized composition,   the hydroprocessing unit includes at least one guard bed to strap solid particles,   step (c) is performed at temperatures of 200° C. or more, or includes at least one treatment performed at a temperature of 200° C. or more.   
     
     
         31 . The process according to  claim 28 , wherein step (c) comprises one of the following features:
 (i) the processing in a steamcracker is performed at temperatures from 800° C. to 1200° C.;   (ii) the processing in a fluid catalytic cracker is performed at temperatures from 500° C. to 550° C.,   (iii) the processing in a hydroprocessing unit is performed at temperatures from 100° C. to 500° C.,   (iv) the processing in the isomerization unit is performed at temperatures from 250 to 400° C.,   (v) the separation into usable streams is performed by distillation.