Synthesis of graphene-modified polyurethane foam membrane for separating water from an oil-water mixture

Patent metadata

Field	Value
Publication number	US-12458929-B2
Application number	US-202318312304-A
Country	US
Kind code	B2
Filing date	May 4, 2023
Priority date	May 4, 2023
Publication date	Nov 4, 2025
Grant date	Nov 4, 2025

Abstract

A method for synthesizing a hydrophilic graphene-modified polyurethane foam membrane, is described. The method includes functionalizing graphene oxide particles with tartronic acid to form a functionalized product having a hydrophilic functional group; and reacting the functionalized product with a polyurethane to form the hydrophilic graphene-modified polyurethane foam membrane. The hydrophilic graphene-modified polyurethane foam membrane has a water adsorption capacity of at least 20 g/g. The hydrophilic graphene-modified polyurethane foam membrane is adapted for a use selected from the use group consisting of oil and water separation, water treatment, desalination, and pharmaceutical filtration.

First claim

The invention claimed is:

1 . A method for synthesizing a hydrophilic graphene-modified polyurethane foam membrane, comprising:
functionalizing graphene oxide particles with tartronic acid to form a functionalized product having a hydrophilic functional group; and reacting the functionalized product with a polyurethane to form the hydrophilic graphene-modified polyurethane foam membrane, wherein the hydrophilic graphene-modified polyurethane foam membrane has a water adsorption capacity of at least 20 g/g.

2 . The method of claim 1 , wherein functionalizing graphene oxide particles with tartronic acid comprises:
sonicating graphene oxide in an alcohol/water mixture to form a first reaction mixture; mixing tartronic acid with the first reaction mixture and sonicating to form a second reaction mixture; adding a carbodiimide catalyst to the second reaction mixture and sonicating to form a third reaction mixture comprising the functionalized product; centrifuging the third reaction mixture to collect the functionalized product; and drying the functionalized product.

3 . The method of claim 2 , wherein the sonicating to form the first reaction mixture occurs for at least two hours.

4 . The method of claim 2 , wherein the carbodiimide is N,N′-dicyclohexylcarbodiimide.

5 . The method of claim 2 , wherein the drying occurs for at least twenty-four hours at 60° C. under a vacuum.

6 . The method of claim 1 , wherein the reacting the functionalized product with polyurethane comprises:
mixing the functionalized product with the polyurethane in a polar protic solvent to form a mixture; sonicating the mixture; refluxing the mixture; and drying the mixture to form the hydrophilic graphene-modified polyurethane foam membrane.

7 . The method of claim 1 , wherein the ratio of the functionalized product with the polyurethane is in the range of 1:2 to 1:5 by weight.

8 . The method of claim 1 , further comprising
synthesizing the graphene oxide particles by oxidizing a waste graphite powder, wherein at least 95% by weight of the graphite in the graphene oxide particles is from the waste graphite powder.

9 . The method of claim 1 , wherein the graphene oxide particles comprise epoxy functional groups, hydroxyl functional groups, and carboxyl functional groups.

10 . The method of claim 1 , wherein the graphene oxide particles comprises one or more carboxyl functional groups that are covalently bonded to one or more hydroxyl groups of the tartronic acid.

11 . The method of claim 1 , wherein the functionalized product has a nanosheet structure.

12 . The method of claim 1 , wherein one or more carbon atoms in the graphene oxide in the functionalized product is bonded covalently to one or more amides in the polyurethane.

13 . The method of claim 1 , wherein the hydrophilic graphene-modified polyurethane foam membrane has a porous morphology with pores ranging in size from 100 micrometers to 800 micrometers in diameter.

14 . The method of claim 1 , wherein the hydrophilic graphene-modified polyurethane foam membrane has an oil contact angle from 145° to 160°.

15 . The method of claim 1 , further comprising:
contacting the hydrophilic graphene-modified polyurethane foam membrane with an oil-water mixture to permeate the water from the oil-water mixture through the hydrophilic graphene-modified polyurethane foam membrane and block the oil from the oil-water mixture from permeating through the hydrophilic graphene-modified polyurethane foam membrane.

16 . The method of claim 15 , wherein contacting the hydrophilic graphene-modified polyurethane foam membrane with the oil-water mixture results in a separation efficiency of oil and water of at least 96%.

17 . The method of claim 15 , wherein contacting the hydrophilic graphene-modified polyurethane foam membrane with the oil-water mixture results in a flux from 30,925 L m −2 h −1 to 30,500 L m −2 h −1 in a range of 1 to 50 cycles.

18 . The method of claim 15 , further comprising:
wetting the hydrophilic graphene-modified polyurethane foam membrane with water before contacting the hydrophilic graphene-modified polyurethane foam membrane with the oil-water mixture.

19 . The method of claim 15 , wherein the oil in the oil-water mixture is one or more of toluene, cyclohexane, n-hexane, dichloromethane, and waste oil.

20 . The method of claim 1 , wherein the hydrophilic graphene-modified polyurethane foam membrane is adapted for a use selected from the use group consisting of oil and water separation, water treatment, desalination, and pharmaceutical filtration.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Saleh Tawfik Abdo

Classifications

• B01J20/265

  modified or post-treated polymers (polymer carriers or substrates subjected to further impregnating or coating B01J20/3208) · CPC title

• B01D2325/20

  Specific permeability or cut-off range · CPC title

• B01D2323/36

  Introduction of specific chemical groups · CPC title

• B01D2323/12

  Specific ratios of components used · CPC title

• B01D2323/081

  Heating · CPC title