Adsorption of aromatic hydrocarbons from water using metal oxide impregnated carbon nanotubes

Patent metadata

Field	Value
Publication number	US-2017057839-A1
Application number	US-201514842351-A
Country	US
Kind code	A1
Filing date	Sep 1, 2015
Priority date	Sep 1, 2015
Publication date	Mar 2, 2017
Grant date	—

Abstract

Methods and nanocomposites for the adsorptive removal of aromatic hydrocarbons such as benzene, toluene, ethyl benzene and xylene from contaminated water sources and systems are provided. The nanocomposites contain carbon nanotubes and metal oxide nanoparticles such as Al 2 O 3 , Fe 2 O 3 and ZnO impregnated on a surface and/or in pore spaces of the carbon nanotubes. Methods of preparing and characterizing the nanocomposite adsorbents are also provided.

First claim

1 . A method for removing at least one aromatic hydrocarbon from an aqueous solution, comprising;
contacting a nanocomposite comprising carbon nanotubes and metal oxide nanoparticles with the aqueous solution to adsorb the aromatic hydrocarbon from the aqueous solution, wherein the metal oxide nanoparticles are impregnated on a surface and/or in pore spaces of the carbon nanotubes.

2 . The method of claim 1 , wherein the metal oxide is at least one selected from the group consisting of aluminum oxide, zinc oxide and iron oxide.

3 . The method of claim 1 , wherein the carbon nanotubes are at least one selected from the group consisting of multi walled carbon nanotubes, single walled carbon nanotubes and hybrid nanotubes.

4 . The method of claim 1 , wherein the aromatic hydrocarbon is at least one selected from the group consisting of benzene, toluene, ethyl benzene and xylene.

5 . The method of claim 1 , wherein the carbon nanotubes are present in the nanocomposite in at least 85% by weight relative to the total weight of the nanocomposite and the metal oxide nanoparticles are present in the nanocomposite in up to 15% by weight relative to the total weight of the nanocomposite.

6 . The method of claim 1 , wherein the metal oxide nanoparticles have an average particle size of 1-50 nm.

7 . The method of claim 1 , wherein the carbon nanotubes have an average outer diameter in the range of 1-75 nm and an average inner diameter in the range of 0.5-50 nm.

8 . The method of claim 1 , wherein the nanocomposite has a BET surface area of at least 100 m 2 /g.

9 . The method of claim 1 , further comprising agitating the aqueous solution at a speed of 50-350 rpm during the contacting.

10 . The method of claim 1 , wherein at least 25% of the total mass of the aromatic hydrocarbon is removed from the aqueous solution.

11 . The method of claim 1 , wherein up to 90% of the total mass of the aromatic hydrocarbon is removed from the aqueous solution.

12 . The method of claim 11 , wherein the contacting is carried out for a time of up to 5 hours.

13 . The method of claim 1 , wherein the nanocomposite is effective at removing at least 25% of the total mass of at least one aromatic hydrocarbon from the aqueous solution in a dosage of 10-200 mg per 1 ppm of aromatic hydrocarbon.

14 . The method of claim 1 , wherein the contacting increases the adsorption of the aromatic hydrocarbon compared to substantially the same method performed under substantially the same operating conditions without the metal oxide nanoparticles.

15 . The method of claim 1 , wherein the total mass of the aromatic hydrocarbon removed increases 10-40% compared to substantially the same method performed under substantially the same operating conditions without metal oxide nanoparticles.

16 . A nanocomposite, comprising;
carbon nanotubes, which are present in at least 85% by weight relative to the total weight of the nanocomposite, and nanoparticles comprising at least one metal oxide selected from the group consisting of aluminum oxide, zinc oxide and iron oxide, which are present in up to 15% by weight relative to the total weight of the nanocomposite, wherein the metal oxide nanoparticles are impregnated on a surface and/or in pore spaces of the carbon nanotubes, and wherein contacting the nanocomposite to an aqueous solution comprising at least one aromatic hydrocarbon selected from the group consisting of benzene, toluene, ethyl benzene, and xylene results in adsorption of at least 25% of the total mass of the aromatic hydrocarbon from the aqueous solution.

17 . The nanocomposite of claim 16 , wherein the total mass of the aromatic hydrocarbon removed increases 10-40% compared to substantially the same nanocomposite without metal oxide nanoparticles.

18 . The nanocomposite of claim 16 , wherein the nanocomposite has a BET surface area of at least 100 m 2 /g.

19 . A process for forming the nanocomposite of claim 16 , comprising;
adding a solution of a metal salt to a suspension of carbon nanotubes to form a reaction mixture, sonicating the reaction mixture to form metal oxide impregnated carbon nanotubes, drying the metal oxide impregnated carbon nanotubes at a first temperature, then calcining the metal oxide impregnated carbon nanotubes at a second temperature to form the nanocomposite.

20 . The process of claim 19 , wherein the carbon nanotubes are at least one selected from the group consisting of multi walled carbon nanotubes, single walled carbon nanotubes and hybrid nanotubes and wherein the metal salt comprises at least one selected from the group consisting of aluminum nitrate, zinc nitrate and iron nitrate.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Atieh Muataz Ali
• Abbas Aamir
• Abussaud Basim Ahmed

Classifications

• C02F2101/322

  Volatile compounds, e.g. benzene · CPC title

• C02F2103/38

  Polymers · CPC title

• C02F2305/08

  Nanoparticles or nanotubes · CPC title

• B01J20/205

  Carbon nanostructures, e.g. nanotubes, nanohorns, nanocones, nanoballs (carbon nanotubes per se C01B32/15) · CPC title

• B01J20/28061

  being in the range 100-500 m2/g · CPC title