Hydrogen sulphide and mercaptans scavenging compositions

Abstract

The present invention relates to a composition for scavenging hydrogen sulphide and/or mercaptans in hydrocarbon streams, the composition comprising an oxazolidine compound and a synergistic additive.

1 - 15 . (canceled) 
     
     
         16 . A composition for scavenging hydrogen sulphide and mercaptans in hydrocarbon streams, said composition comprising an oxazolidine compound and an additive, said additive being a modified alkylphenol-aldehyde resin obtainable by a Mannich reaction of an alkylphenol-aldehyde condensation resin,
 with at least one aldehyde and/or one ketone having 1 to 8 carbon atoms; and   at least one hydrocarbon compound having at least one alkylmonoamine or alkylpolyamine group having from 2 to 30 carbon atoms,   optionally with at least one alkylene oxide;   said alkylphenol-aldehyde condensation resin being obtainable by condensation;   of at least one alkylphenol substituted by at least one linear or branched alkyl group having 1 to 30 carbon atoms; and   at least one aldehyde and/or one ketone having 1 to 8 carbon atoms.   
     
     
         17 . The composition according to  claim 16 , wherein the alkylphenol substituted by at least one linear or branched alkyl group having 1 to 30 carbon atoms is substituted in para position. 
     
     
         18 . The composition according to  claim 16 , wherein aldehyde and/or a ketone is chosen from formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, 2-ethyl hexanal, benzaldehyde, or acetone. 
     
     
         19 . The composition according to  claim 16 , wherein the hydrocarbon compound having at least one alkylmonoamine or alkylpolyamine group having from 2 to 30 carbon atoms is selected from alkylamines having at least one primary amine group. 
     
     
         20 . The composition according to  claim 16 , wherein the modified alkylphenol-aldehyde resin is obtainable from p-nonylphenol, formaldehyde and at least one hydrocarbon compound having at least one alkylmonoamine or alkylpolyamine group having from 2 to 30 carbon atoms having at least one primary amine group, and optionally with alkylene oxide selected from ethylene oxide and propylene oxide. 
     
     
         21 . The composition according to  claim 16 , wherein the oxazolidine compound is a selected from bisoxazolidines. 
     
     
         22 . The composition according to  claim 16 , wherein the composition comprises from 19 to 99% wt of oxazolidine compound(s) and from 1 to 50% wt of said additive(s), based on the total weight of the composition. 
     
     
         23 . The composition according to  claim 16 , wherein the weight ratio of oxazolidine compound(s) to said additive(s) ranges from 1 to 100. 
     
     
         24 . The composition according to  claim 16 , further comprising a solvent. 
     
     
         25 . The composition according to  claim 16 , comprising:
 From 19 to 80% wt of oxazolidine compound(s),   From 1 to 30% wt of said additive(s), and   From 1 to 80% wt of solvent(s),   based on the total weight of the composition.   
     
     
         26 . Process for improving the efficiency of an oxazolidine compound for scavenging hydrogen sulphide and/or mercaptans in hydrocarbon streams, the process comprising a step of adding the additive defined in  claim 16  in an oxazolidine compound. 
     
     
         27 . Hydrocarbon stream comprising hydrocarbons and a composition according to  claim 16 . 
     
     
         28 . Hydrocarbon streams according to  claim 27 , wherein the hydrocarbons are selected from crude oil, fuel oil, fuel, Light Petroleum Gas and natural gas. 
     
     
         29 . A method for scavenging hydrogen sulphide and/or mercaptan in a hydrocarbon stream, comprising contacting the hydrocarbon stream with the composition according to  claim 16 . 
     
     
         30 . The method according to  claim 29 , wherein the weight ratio between hydrogen sulphide contained in the hydrocarbon stream before the step of contacting and the composition ranges from 1:2 to 1:0.05. 
     
     
         31 . The composition according to  claim 16 , wherein the alkylphenol substituted by at least one linear or branched alkyl group having 1 to 30 carbon atoms is p-nonylphenol. 
     
     
         32 . The composition according to  claim 16 , wherein the hydrocarbon compound having at least one alkylmonoamine or alkylpolyamine group having from 2 to 30 carbon atoms is selected from hydrocarbon compounds compound, all the amine groups of which are primary amines. 
     
     
         33 . The composition according to  claim 24 , wherein the solvent is present in an amount ranging from 1 to 80% wt, based on the total weight of the composition.