Rice-husk derived silicon carbide membrane sorbent for oil removal

Patent metadata

Field	Value
Publication number	US-2021237003-A1
Application number	US-202016782662-A
Country	US
Kind code	A1
Filing date	Feb 5, 2020
Priority date	Feb 5, 2020
Publication date	Aug 5, 2021
Grant date	—

Abstract

A membrane sorbent is described, which comprises 1-6 wt % silicon carbide nanoparticles dispersed in a polymer matrix. The polymer matrix may comprise polysulfone and polyvinylpyrrolidone. The membrane sorbent is used for separating oil from a contaminated water mixture. The silicon carbide nanoparticles of the membrane sorbent may be made from rice husk ash.

First claim

1 . A membrane sorbent, comprising:
silicon carbide nanoparticles dispersed in a polymer matrix, the polymer matrix comprising: a polysulfone polymer, and a second polymer; wherein the membrane sorbent comprises the silicon carbide nanoparticles at a weight percentage in a range of 1-6 wt % relative to the total weight of the membrane sorbent.

2 . The membrane sorbent of claim 1 , wherein a weight ratio of the polysulfone polymer to the second polymer is in a range of 1.0-5.0.

3 . The membrane sorbent of claim 1 , which has a porosity in a range of 55-70%.

4 . The membrane sorbent of claim 1 , wherein the silicon carbide nanoparticles have a surface area in a range of 80 to 180 m 2 /g.

5 . The membrane sorbent of claim 1 , wherein the silicon carbide nanoparticles have an average pore size in a range of 2.7 to 3.5 nm and a pore volume in a range of 0.15 to 0.35 cm 3 /g.

6 . The membrane sorbent of claim 1 , wherein the second polymer is at least one selected from the group consisting of polyvinylpyrrolidone, polyethylene, polypropylene, polyisobutylene, polystyrene, polyvinylchloride, and ethylene vinyl acetate copolymer.

7 . The membrane sorbent of claim 6 , wherein the second polymer is polyvinylpyrrolidone.

8 . The membrane sorbent of claim 7 , consisting essentially of the silicon carbide nanoparticles and the polymer matrix, and
wherein the polymer matrix consists essentially of the polysulfone polymer and polyvinylpyrrolidone.

9 . The membrane sorbent of claim 1 , wherein the membrane sorbent is hydrophilic, having an exterior surface with a water drop contact angle in a range of 30°-45°.

10 . A method for separating oil from a contaminated water mixture with the membrane sorbent of claim 1 , the method comprising:
contacting the contaminated water mixture comprising oil with a feed side of a vessel comprising the membrane sorbent, wherein the membrane sorbent divides the vessel into a feed side and a permeate side, and wherein at least a portion of the contaminated water mixture permeates through to the permeate side of the vessel, and recovering from the permeate side a filtered water product depleted in oil compared with the contaminated water mixture.

11 . The method of claim 10 , wherein the filtered water product has a total organic carbon content by mass that is 88-100% less than a total organic carbon content of the contaminated water mixture.

12 . The method of claim 10 , wherein a pressure difference between the feed side and the permeate side is in a range of 0.5-8.0 bar.

13 . The method of claim 12 , wherein a flux of the contaminated water mixture through a feed side of the membrane sorbent is in a range of 65-150 L·m −2 ·h −1 .

14 . The method of claim 10 , wherein the contaminated water mixture is an oil-in-water emulsion, and the oil is a petroleum product.

15 . The method of claim 10 , wherein the contaminated water mixture further comprises sodium dodecyl sulfate.

16 . The method of claim 10 , having an oil rejection that is at least 10% greater than a substantially similar membrane sorbent that does not comprise silicon carbide.

17 . A method of making the membrane sorbent of claim 1 , comprising
mixing silicon carbide nanoparticles, the polysulfone polymer, and the second polymer in a solvent to produce a mixture, casting a film from the mixture, and contacting the film with water to produce the membrane sorbent.

18 . The method of claim 17 , wherein the nSiC is produced from rice husk ash by mixing the rice husk ash with a polysiloxane and a solvent to form a reaction mixture,
heating the reaction mixture to a temperature in a range of 750 to 1250° C. to produce a bulk silicon carbide, and milling the bulk silicon carbide to produce the silicon carbide nanoparticles.

19 . The method of claim 17 , wherein the solvent is dimethylacetamide.

20 . The method of claim 17 , wherein the film is cast to a thickness in a range of 50-200 μm.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Aljundi Isam H
• Basheer Chanbasha
• Bakdash Rashed Saed

Classifications

• B01D2325/02831

  less than 1 nm · CPC title

• B01D67/00113

  Pretreatment of the casting solutions, e.g. thermal treatment or ageing · CPC title

• B01D67/0013

  Casting processes · CPC title

• B01D71/441

  Polyvinylpyrrolidone · CPC title

• B01D69/14111

  with nanoscale dispersed material, e.g. nanoparticles · CPC title