Method for removing single ring aromatic hydrocarbons

Patent metadata

Field	Value
Publication number	US-9981863-B2
Application number	US-201615018898-A
Country	US
Kind code	B2
Filing date	Feb 9, 2016
Priority date	Feb 9, 2016
Publication date	May 29, 2018
Grant date	May 29, 2018

Abstract

A method of removing at least one single ring aromatic hydrocarbon from a hydrocarbon contaminated fluid. The method includes contacting the hydrocarbon contaminated fluid with carbon nanotubes to adsorb the at least one single ring aromatic hydrocarbon while exposing the hydrocarbon contaminated fluid and the carbon nanotubes to UV irradiation from at least one UV light source, preferably a UV light emitting diode (LED), with a wavelength of about 315-415 nm, preferably about 365 nm, to form a treated fluid having a reduced concentration of the at least one single ring aromatic hydrocarbon relative to the hydrocarbon contaminated fluid.

First claim

The invention claimed is:

1. A method of removing at least one single ring aromatic hydrocarbon from a hydrocarbon contaminated fluid, comprising:
contacting the hydrocarbon contaminated aqueous solution with unmodified multiwalled carbon nanotubes to adsorb the at least one single ring aromatic hydrocarbon while exposing the hydrocarbon contaminated aqueous solution and the unmodified multiwalled carbon nanotubes to UV irradiation from at least one LED UV light source with a wavelength of about 315-415 nm to form a treated fluid having a reduced concentration of the at least one single ring aromatic hydrocarbon relative to the hydrocarbon contaminated aqueous solution,
wherein the at least one single ring aromatic hydrocarbon is selected from the group consisting of benzene, toluene, ethylbenzene, ortho-xylene, meta-xylene, para-xylene, cumene, and styrene.

2. The method of claim 1 ,
wherein the at least one single ring aromatic hydrocarbon is para-xylene, and
wherein the method reduces the concentration of para-xylene in the aqueous solution by at least 30% in less time than a substantially similar method without contacting the aqueous solution with the carbon nanotubes.

3. The method of claim 1 ,
wherein the at least one single ring aromatic hydrocarbon is para-xylene, and
wherein the method reduces the concentration of para-xylene in the aqueous solution by at least 30% in less time than a substantially similar method without exposing the aqueous solution and the carbon nanotubes to the UV irradiation.

4. The method of claim 1 ,
wherein the at least one single ring aromatic hydrocarbon is para-xylene, and
wherein the reduced concentration of the para-xylene in the treated fluid is at least 95% reduced relative to the hydrocarbon contaminated fluid.

5. The method of claim 1 , wherein the unmodified multiwalled carbon nanotubes have an outer diameter ranging from about 8 nm to 80 nm.

6. The method of claim 1 , wherein the amount of the unmodified multiwalled carbon nanotubes contacting the hydrocarbon contaminated aqueous solution ranges from about 0.2 g/L to 1 g/L of the hydrocarbon contaminated aqueous solution.

7. The method of claim 1 , wherein the hydrocarbon contaminated aqueous solution has a pH of about 6-8 before the contacting and the exposing.

8. The method of claim 1 , wherein the hydrocarbon contaminated aqueous solution is contacted with the unmodified multiwalled carbon nanotubes while the hydrocarbon contaminated aqueous solution and the unmodified multiwalled carbon nanotubes are exposed to the UV irradiation at a temperature of about 20-30° C. and a pressure of about 0.5-1.5 bar.

9. The method of claim 1 , wherein a plurality of the unmodified multiwalled carbon nanotubes is in a powder form.

10. The method of claim 1 , wherein the contacting forms adsorbed unmodified multiwalled carbon nanotubes comprising at least one single ring aromatic hydrocarbon and the method further comprises removing the adsorbed unmodified multiwalled carbon nanotubes from the treated fluid.

11. The method of claim 10 , further comprising regenerating the adsorption ability of the adsorbed unmodified multiwalled carbon nanotubes.

12. The method of claim 1 , wherein during the contacting the hydrocarbon contaminated aqueous solution is stirred with the unmodified multiwalled carbon nanotubes.

13. The method of claim 1 , wherein during the contacting an hydrocarbon contaminated aqueous solution comprising 100 ppm of the single ring aromatic hydrocarbon is stirred with a suspension of the unmodified multiwalled carbon nanotubes at in ratio of about (500mg unmodified multiwalled carbon nanotubes)/(1,000 ml of the contaminated aqueous solution).

14. The method of claim 1 , comprising:
contacting the hydrocarbon contaminated aqueous solution with the unmodified multiwalled carbon nanotubes for 30 minutes to form a treated fluid comprising 5 ppm or less of the single ring aromatic hydrocarbon, and
contacting the hydrocarbon contaminated aqueous solution with the unmodified multiwalled carbon nanotubes for 120 minutes to remove all of the single ring aromatic hydrocarbon.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Abussaud Basim Ahmed
• Abbas Aamir

Classifications

• C02F2101/32

  Hydrocarbons, e.g. oil · CPC title

• C02F2201/3222

  Units using UV-light emitting diodes [LED] · CPC title

• C02F1/325 Primary

  Irradiation devices or lamp constructions · CPC title

• C02F1/283

  using coal, charred products, or inorganic mixtures containing them · CPC title

• C02F2305/08

  Nanoparticles or nanotubes · CPC title