Use of sulfiding agents for enhancing the efficacy of phosphorus in controlling high temperature corrosion attack
AssigneeNalco/Exxon Energy Chemicals, L.P.
InventorsElizabeth Babaian-Kibala, John G. Hyatt, Theodore J. Rose
Life of this patent
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Abstract
The invention comprises a method of inhibiting naphthenic acid corrosion in a high temperature hydrocarbon system, comprising adding to the system a corrosion-inhibiting amount of a phosphate ester and a corrosion-inhibiting amount of organic polysulfide.
Claims15
A method of inhibiting naphthenic acid corrosion occurring on the metal surfaces of a high temperature hydrocarbon system in contact with a crude oil containing naphthenic acid comprising adding simultaneously to the crude oil:
- a) corrosion-inhibiting amount of a phosphate ester of the formula ##STR2## wherein R.sub.1 and R.sub.2 are each independently selected from the group consisting of hydrogen and moieties having from one to thirty carbon atoms, and R.sub.3 is a moiety having from one to thirty carbon atoms;
- and
- b) a corrosion inhibiting amount of an organic polysulfide of the formula R.sub.4 --(S).sub.x --R.sub.5 wherein R.sub.4 and R.sub.5 are selected from the group consisting of alkyl groups having from 6 to 30 carbon atoms, and cycloalkyl groups having from 6 to 30 carbon atoms and x ranges from 2 to 6, and wherein the ratio of such polysulfide to said phosphate ester ranges from 4:0.25 to 0.25:4.
A method of inhibiting naphthenic acid corrosion occurring on the metal surfaces of a high temperature hydrocarbon system in contact with a crude oil containing naphthenic acid comprising adding simultaneously to the crude oil:
- a) corrosion-inhibiting amount of a phosphate ester of the formula ##STR3## wherein R.sub.1 and R.sub.2 are each independently selected from the group consisting of hydrogen and moieties having from one to thirty carbon atoms, and R.sub.3 is a moiety having form one to thirty carbon atoms;
- and
- b) a corrosion inhibiting amount of an organic polysulfide of the formula R.sub.4 --(S).sub.x --R.sub.5 wherein R.sub.4 and R.sub.5 are selected from the group consisting of alkyl groups having from 6 to 30 carbon atoms, and cycloalkyl groups having from 6 to 30 carbon atoms and x ranges from 2 to 6, and wherein the ratio of such polysulfide to said phosphate ester ranges from 3:1 to 0.25:4.
A method of inhibiting naphthenic acid corrosion occurring on the metal surfaces of a high temperature hydrocarbon system in contact with a crude oil containing naphthenic acid comprising adding simultaneously to the crude oil:
- a) a corrosion-inhibiting amount of a phosphate ester of the formula ##STR4## where R.sub.1 and R.sub.2 are each independently selected from the group consisting of hydrogen and moieties having from one to thirty carbon atoms, and R.sub.3 is a moiety having from one to thirty carbon atoms;
- and
- b) a corrosion-inhibiting amount of an organic polysulfide of the formula R.sub.4 --(S).sub.x --R.sub.5 wherein R.sub.4 and R.sub.5 are selected from the group consisting of alkyl groups having from 6 to 30 carbon atoms, and cycloalkyl groups having from 6 to 30 carbon atoms and x ranges from 2 to 6, and wherein the ratio of said polysulfide to said phosphate ester ranges from 1:1 to 1:4.
Dependencies are inferred from the claim text.