IP Library › Granted Patent US 12,326,437
Granted Patent B2
US 12,326,437 · App. 18/335,664 · Granted Jun 10, 2025

Elemental sulfur analysis in fluids

Inventors: Jay Locklear (Houston, TX); Clinton Crowe (Houston, TX)
Assignee: CONOCOPHILLIPS COMPANY
G01N33/287G01N21/75Y10T436/109163Y10T436/188
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Quick Facts
Patent No.
US 12,326,437
App. No.
18/335,664
Granted
Jun 10, 2025
Kind
B2
Abstract

Robust methods for quantitating the amount of elemental sulfur in a fluid whereby a caustic solution is mixed with the fluid, and the elemental sulfur present in the fluid reacts to form a colored solution that can be compared to a series of standards. The methods can be performed in a laboratory or the field and allow for real time feedback. Once the concentration of the elemental sulfur is known, appropriate methods of treatment can proceed. Test kits for performing the methods in the field are also described.

Claims (24)

1. An elemental sulfur test kit comprising a storage container comprising:

a) a first container containing a solution having a known amount of a caustic chemical comprising tetrabutylammonium hydroxide;

b) a second container containing a known amount of a hydrocarbon solvent;

c) a third container containing a known amount of an alcohol;

d) a fourth container containing a known concentration of elemental sulfur; and

e) a set of instructions for mixing said caustic chemical, said hydrocarbon solvent, said alcohol, and a fluid selected from the group consisting of gasoline, jet fuel, kerosene, condensates, black oils, solid hydrocarbons solubilized in liquid hydrocarbons, produced water, and combinations thereof, and using said known concentration of elemental sulfur to determine an amount of elemental sulfur in said fluid.

2. The test kit of claim 1 , said storage container further comprising a plurality of cuvettes and a plurality of pipettes for transferring solutions into the plurality of cuvettes, wherein each cuvette of said plurality of cuvettes has a cap such that it said cuvette can be used for mixing at least two of said caustic chemical, said hydrocarbon solvent, said alcohol, and said known concentration of elemental sulfur.

3. The test kit of claim 1 , wherein:

said hydrocarbon solvent is selected from a group consisting of gasoline, diesel, kerosene, hexane, benzene, toluene, xylene, heavy aromatic naphtha, mixtures of naphtha and naphthalene, and naphthalene, and

said alcohol is selected from a group consisting of methanol, ethanol, isopropyl alcohol, and butanol.

4. The test kit of claim 1 , wherein said alcohol is a C1-C4 alcohol.

5. The test kit of claim 1 , wherein said hydrocarbon solvent is toluene.

6. An elemental sulfur test kit comprising a storage container comprising:

a) a first container containing a caustic solution having a known amount of a caustic chemical comprising tetrabutylammonium hydroxide in a known amount of an alcohol;

b) a second container containing a known amount of a hydrocarbon solvent;

c) a third container containing a known amount of elemental sulfur; and

d) a set of instructions for using said caustic solution, said hydrocarbon solvent, and said known amount of elemental sulfur to determine an amount of elemental sulfur in a fluid, said fluid selected from the group consisting of gasoline, jet fuel, kerosene, condensates, black oils, solid hydrocarbons solubilized in liquid hydrocarbons, produced water, and combinations thereof.

7. The test kit of claim 6 , said caustic solution comprising tetrabutylammonium hydroxide and C1-C4 alcohol.

8. The test kit of claim 6 , said caustic solution being comprising tetrabutylammonium hydroxide and C1-C4 alcohol and said hydrocarbon solvent being toluene.

9. An elemental sulfur test kit comprising a storage container comprising:

a) a first container containing a caustic solution, said caustic solution comprising tetrabutylammonium hydroxide, a C1-C4 alcohol and a hydrocarbon solvent;

b) a second container containing a known amount of elemental sulfur; and

c) a set of instructions for using said caustic solution and said known amount of elemental sulfur to determine an amount of elemental sulfur in a fluid, said fluid selected from the group consisting of gasoline, jet fuel, kerosene, condensates, black oils, solid hydrocarbons solubilized in liquid hydrocarbons, produced water, and combinations thereof.

10. The test kit of claim 9 , said hydrocarbon solvent being toluene.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 15, 2023
From: LOCKLEAR, JAY; CROWE, CLINTON
To: CONOCOPHILLIPS COMPANY
Reel/Frame 063965/0083 →
Continuity (3)
Division 17062281 · Oct 2, 2020
Provisional Application 62910501 · Oct 4, 2019
Related Publication 20230324361A1 · Oct 12, 2023
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