Elemental sulfur analysis in fluids

Patent metadata

Field	Value
Publication number	US-11719684-B2
Application number	US-202017062281-A
Country	US
Kind code	B2
Filing date	Oct 2, 2020
Priority date	Oct 4, 2019
Publication date	Aug 8, 2023
Grant date	Aug 8, 2023

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.

First claim

The invention claimed is:

1. A method of determining an amount of elemental sulfur S8 in a fluid, said method comprising adding tetrabutylammonium hydroxide 30-hydrate in an organic solvent to said fluid to obtain a colored solution; measuring absorbance of said colored solution at a wavelength between 190-750 nm; comparing said measured absorbance of said colored solution with an absorbance of a standard solutions of elemental sulfur S8 of known concentrations to determine a concentration of elemental sulfur S8 in said fluid.

2. The method of claim 1 , wherein a concentration of said tetrabutylammonium hydroxide 30-hydrate in the organic solvent is between about 0.01 and 0.1 M.

3. The method of claim 1 , wherein said organic solvent is an alcohol.

4. The method of claim 1 , wherein a volume ratio of said tetrabutylammonium hydroxide 30-hydrate in organic solvent to said fluid is 5:1.

5. The method of claim 1 , wherein 10 mL of a tetrabutylammonium hydroxide 30-hydrate solution is added to about 0.5 mL of said fluid.

6. The method of claim 1 , wherein the fluid is selected from a group consisting of gasoline, jet fuel, kerosene, condensates, black oils, solid hydrocarbons solubilized in liquid hydrocarbons, produced water, and combinations thereof.

Assignees

• Conocophillips Co

Inventors

• Locklear Jay
• Crowe Clinton

Classifications

• G01N33/287 Primary

  Sulfur content · CPC title

• G01N21/75

  Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated (systems in which material is burnt in a flame or plasma G01N21/72, G01N21/73) · CPC title

• Y10T436/109163

  Inorganic standards or controls · CPC title

• Y10T436/188

  Total or elemental sulfur · CPC title

• G01N21/78

  producing a change of colour · CPC title