450 nm visible light-induced photosensitized degradation of rhodamine B molecules over BiOBr in aqueous solution

Patent metadata

Field	Value
Publication number	US-9399576-B2
Application number	US-201414154810-A
Country	US
Kind code	B2
Filing date	Jan 14, 2014
Priority date	Jan 14, 2014
Publication date	Jul 26, 2016
Grant date	Jul 26, 2016

Abstract

A method for degrading Rhodamine B including: mixing BiOBr and Rhodamine B; and irradiating the mixture with a radiation having a wavelength of from 440 nm to 554 nm. The Rhodamine B may be in an aqueous solution. The BiOBr may be added to the aqueous solution of Rhodamine B in an amount of from 0.2 to 0.5 mg/ml. The BiOBr may have a sheet-like structure with particles having a diameter of from 3 μm to 5 μm. The BiOBr may be in a pure crystal tetragonal phase.

First claim

What is claimed is:

1. A method for degrading Rhodamine B comprising:
mixing BiOBr and an aqueous solution of Rhodamine B; and
irradiating the mixture with a radiation having a wavelength of from 440 nm to 554 nm,
wherein the BiOBr is added to the aqueous solution of Rhodamine B in an amount of from 0.2 to 0.5 mg/ml, and
wherein the BiOBr has a sheet-like structure with a diameter of from 3 μm to 5 μm.

2. The method of claim 1 , wherein the aqueous solution of the Rhodamine B is free of hydroxyl radical scavengers.

3. The method of claim 1 , wherein the mixture is irradiated with a radiation having a wavelength of 450 nm.

4. The method of claim 3 , wherein the radiation is monochromatic light.

5. The method of claim 1 , wherein the mixture is irradiated at a temperature of from 5° C. to 27° C.

6. The method of claim 1 , wherein the BiOBr is in a pure crystal tetragonal phase.

7. The method of claim 1 , wherein the BiOBr has a band gap of 2.8 eV.

8. The method of claim 1 , wherein the BiOBr is synthesized from sodium bismuth oxide dihydrate and hydrobromic acid.

9. The method of claim 1 , wherein at least 80% of the Rhodamine B is degraded after the irradiation for a period of 60 minutes.

10. The method of claim 1 , wherein the Rhodamine B is photosensitized by the irradiation.

11. The method of claim 1 , wherein BiOBr is the only catalyst present in the mixture during the mixing and the irradiating.

12. The method of claim 1 , wherein the BiOBr is added to the aqueous solution of Rhodamine B in an amount of from 0.3 to 0.5 mg/ml.

13. The method of claim 1 , wherein the BiOBr is added to the aqueous solution of Rhodamine B in an amount of from 0.4 to 0.5 mg/ml.

14. The method of claim 1 , wherein an initial concentration of RhB in the RhB aqueous solution is from 5 to 10 ppm.

15. The method of claim 1 , further comprising, after the irradiating, removing BiOBr from the mixture by centrifugation.

16. The method of claim 1 , wherein the BiOBr has a sheet-like structure with a diameter of about 4 μm.

17. The method of claim 8 , wherein the BiOBr is synthesized by fully dissolving sodium bismuth oxide dihydrate in an aqueous solution of hydrobromic acid, and adding water to precipitate the BiOBr.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Gondal Muhammad Ashraf
• Shen Kai
• Chang Xiafeng
• Yamani Zain Hasan Abdallah

Classifications

• A62D2101/47

  containing oxygen, sulfur, selenium or tellurium, i.e. chalcogen · CPC title

• C01B11/20 Primary

  Oxygen compounds of bromine · CPC title

• A62D3/17 Primary

  to electromagnetic radiation, e.g. emitted by a laser · CPC title

• C01D3/10

  Bromides · CPC title

• A62D2101/45

  containing nitrogen or phosphorus · CPC title