Carbon-based fluorescent tracers as oil reservoir nano-agents

Patent metadata

Field	Value
Publication number	US-9453159-B2
Application number	US-201514627522-A
Country	US
Kind code	B2
Filing date	Feb 20, 2015
Priority date	May 13, 2011
Publication date	Sep 27, 2016
Grant date	Sep 27, 2016

Abstract

The present invention relates to carbon-based fluorescent nano-agent tracers for analysis of oil reservoirs. The carbon-based fluorescent nano-agents may be used in the analysis of the porosity of a formation. The nanoagents are suitable for injection into a petroleum reservoir and may be recovered from the reservoir for the determination of hydrocarbon flow rates and retention times.

First claim

That which is claimed is:

1. A method for the preparation of a fluorescent nanoagent for use in a subsurface petroleum reservoir, the method comprising the steps of:
heating an aqueous mixture of citric acid and an amino alcohol at a temperature of about 70° C. to remove the majority of the water and produce a viscous solution;
heating the viscous solution at a temperature of at least about 200° C. for at least about 2 hours; and
collecting the resulting black particles products, said particles having an average diameter about 10 nm, and wherein said particles include a fluorescent group appended to the surface thereof.

2. The method of claim 1 , wherein the amino alcohol is selected from methanolamine, ethanolamine, and propanolamine.

3. The method of claim 1 , wherein the amino alcohol is ethanolamine.

4. The method of claim 1 , wherein the fluorescent nanoagent is produced from a solution comprising citric acid, an amino alcohol and deionized water reacted under conditions capable of synthesizing the fluorescent nanoagent.

5. The method of claim 1 , wherein the organic functional group is present in an amount of between about 50% and 90% by weight.

6. The method of claim 1 , wherein the fluorescent nanoagent is stable at a temperature of about 100° C. to about 200° C.

7. The method of claim 1 , wherein the fluorescent nanoagent is stable at a salinity concentration of about 75,000 ppm to about 120,000 ppm.

8. The method of claim 1 , wherein the fluorescent group can be excited at a wavelength between about 400 nm and 500 nm.

Assignees

• Saudi Arabian Oil Co
• Univ Cornell

Inventors

• Kanj Mazen Y
• Rashid Mohammad Harunar
• Giannelis Emmanuel

Classifications

• Y10S977/773

  Nanoparticle, i.e. structure having three dimensions of 100 nm or less · CPC title

• C09K2211/10

  Non-macromolecular compounds · CPC title

• E21B49/008

  by injection test; by analysing pressure variations in an injection or production test, e.g. for estimating the skin factor (measuring pressure E21B47/06) · CPC title

• C09K11/65

  containing carbon (in organic compounds C09K11/06) · CPC title

• C09K11/06 Primary

  containing organic luminescent materials · CPC title