Method for removing organic dyes from aqueous solution

Patent metadata

Field	Value
Publication number	US-2025332566-A1
Application number	US-202519256788-A
Country	US
Kind code	A1
Filing date	Jul 1, 2025
Priority date	Sep 28, 2022
Publication date	Oct 30, 2025
Grant date	—

Abstract

Fe—Co core-shell nanospheres and a method for producing the Fe—Co core-shell nanospheres are disclosed. Further disclosed is a method of reducing an organic contaminant in a solution by mixing the Fe—Co core-shell nanospheres with the solution. The Fe—Co core-shell nanosphere includes a shell made of a material having a formula Co x Fe y O (x+1.5y) and a hollow core. The Fe—Co core-shell nanospheres are produced by mixing cobalt nitrate and iron nitrate in a solvent mixture to form a first mixture and mixing urea with the first mixture to form a second mixture. The solvent mixture is removed from the second mixture to form a powder. The powder is ground to form the Fe—Co core-shell nanospheres.

First claim

1 . (canceled)

2 . The method of claim 12 , wherein the Fe—Co core-shell nanosphere, the formula Co x Fe y O (x+1.5y) :
x is in the range of 1 to 5; and
y is in the range of 1 to 10.

3 . The method of claim 12 , wherein the Fe—Co core-shell nanosphere the shell is made of CoFe 2 O 4 .

4 . (canceled)

5 . The method of claim 12 , wherein the Fe—Co core-shell nanosphere the Fe—Co core-shell nanosphere has an average shell thickness of 50 to 100 nm.

6 . The method of claim 12 , wherein the Fe—Co core-shell nanosphere the Fe—Co core-shell nanosphere has a crystallite size (D) of 15 to 25 nm.

7 . The method of claim 12 , wherein the Fe—Co core-shell nanosphere the Fe—Co core-shell nanosphere has a peak at 500 to 600 cm −1 in a Fourier transform infrared spectrum with a transmittance in a range of 30 to 50%.

8 - 11 . (canceled)

12 . A method of adsorbing one or more organic dyes from an aqueous solution, the method comprising:
adjusting the pH of the aqueous solution to 10 or more; then contacting a membrane comprising a Fe—Co core-shell nanosphere with the aqueous solution, wherein the Fe—Co core-shell nanosphere comprises:
a shell made of a material having a formula Co x Fe y O (x+1.5y) , wherein:
x is in the range of 1 to 15; and
y is in the range of 1 to 25;
a hollow core;
wherein the Fe—Co core-shell nanosphere has an average particle diameter of 1.5 to 10 μm, an average shell thickness of 50 to 300 nm and a crystallite size (D) of 15 to 30 nm,
wherein the Fe—Co core-shell nanosphere has a single shell.

13 . (canceled)

14 . The method of claim 12 , wherein the organic dye is a malachite green (MG) dye or a cationic textile dye.

15 . The method of claim 12 ,
wherein the Fe—Co core-shell nanosphere is mixed with the solution for 70 to 200 minutes at 30 to 60° C.

16 . The method of claim 12 , wherein the aqueous solution comprises the organic dye at a concentration of 0.2 to 100 mg/L, and
wherein the Fe—Co core-shell nanosphere is mixed with the aqueous solution at a concentration of 0.1 to 2 mg/L and removes 80 to 99.9% of the organic dye.

17 . The method of claim 12 , wherein the aqueous solution has a water flux of 180 to 260 L/m 2 h through the membrane, and the method achieves an organic dye removal efficiency of 80 to 99%.

18 . The method of claim 12 , wherein an organic dye removal efficiency of 80 to 99% is achieved with 9 to 19% fouling resistances at a pressure of 0.02 to 0.1 bar across the membrane.

Assignees

• Univ Imam Abdulrahman Bin Faisal

Inventors

• Cevik Emre
• Bozkurt Ayhan

Classifications

• B01J8/00

  Chemical or physical processes in general, conducted in the presence of fluids and solid particles; Apparatus for such processes · CPC title

• C02F2209/02

  Temperature · CPC title

• C01G49/0018

  Mixed oxides or hydroxides, (C01G49/0009 takes precedence) · CPC title

• C01G51/40

  Complex oxides containing cobalt and at least one other metal element · CPC title

• B01J20/28011

  Other properties, e.g. density, crush strength · CPC title