Naphthenic acid corrosion inhibitors
AssigneeExxon Chemical Patents Inc.
InventorsPhilip R. Petersen, Frederick P. Robbins, III, William G. Winston
Life of this patent
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Abstract
Naphthenic acid corrosion in refinery distillation units is inhibited by introducing into the units effective amounts of a polysulfide corrosion inhibitor.
Claims7
A method of inhibiting naphthenic acid corrosion of crude oil in a crude oil distillation unit carried out at a temperature above 400 degrees F., said method comprising introducing into the oil an effective amount of an organic polysulfide to inhibit naphthenic acid corrosion, said polysulfide having the following formula:
- R--(S)x--R'
- where:
- R and R' are each alkyl groups having from 6 to 30 carbon atoms, or a cycloalkyl group having from 6 to 30 carbon atoms, or an aromatic group, and may be the same or different;
- and x ranges from 2 to 6.
A method of inhibiting naphthenic acid corrosion in a vacuum distillation unit which comprises continuously introducing into the vacuum distillation unit an effective amount of an organic polysulfide within the concentration range of 10 ppm to 5000 ppm based on the feed stream into the unit to substantially reduce the naphthenic acid corrosion in the unit.
A method of treating a refinery distillation tower for processing oil containing corrosive amounts of naphthenic acid and hydrogen sulfide carried out at temperatures within the range of 400 to 790 degrees F., said method comprising the step of introducing into the oil processed through the tower inhibiting amounts of an organic polysulfide having the following formula:
- R--(S)x--R'
- where:
- R is and R' are each al alkyl or cycloalkyl group containing from 6 to 30 carbon atoms;
- and x ranges from 2 to 6.
Dependencies are inferred from the claim text.