Ultrafiltration TIO2 magnéli phase reactive electrochemical membranes

Patent metadata

Field	Value
Publication number	US-10364169-B2
Application number	US-201615365252-A
Country	US
Kind code	B2
Filing date	Nov 30, 2016
Priority date	Nov 30, 2015
Publication date	Jul 30, 2019
Grant date	Jul 30, 2019

Abstract

The disclosure generally relates to reactive electrochemical membranes (REMs); and in particular, to asymmetric reactive electrochemical membranes to be used for aqueous separations and membrane fouling regeneration.

First claim

What is claimed is:

1. A reactive electrochemical membrane comprising
a support layer having a median pore diameter size of 1 μm to 10 μm; and
an active layer disposed adjacent to and in contact with the support layer, and having a median pore diameter size of less than 1 μm,

wherein the median pore diameter of the support layer is at least 50% bigger than the median pore diameter of the active layer, and
wherein the support layer and the active layer independently comprise at least 80 wt % oxides of titanium, and wherein the oxides of titanium comprise at least 80 wt % of one or more of Magnéli-phase titanium oxides of the formula Ti n O 2n−1 , wherein n is an integer 4, 5, or 6.

2. The reactive electrochemical membrane of claim 1 , wherein the support layer and the active layer independently comprise at least 95 wt % oxides of titanium.

3. The reactive electrochemical membrane of claim 1 , wherein the oxides of titanium comprise at least 90 wt % of one or more of Magnéli-phase titanium oxides of the formula Ti n O 2n−1 .

4. The reactive electrochemical membrane of claim 3 , wherein n is 4.

5. The reactive electrochemical membrane of claim 1 , wherein each of the support layer and the active layer comprises of Ti 4 O 7 .

6. The reactive electrochemical membrane of claim 1 , wherein each of the support layer and the active layer consists of a mixture of Ti 4 O 7 and Ti 6 O 11 .

7. The reactive electrochemical membrane of claim 1 , wherein the active layer has a median pore diameter size of 10 nm to 1 μm.

8. The reactive electrochemical membrane of claim 1 , wherein the active layer has a thickness of 10 μm to 100 μm.

9. The reactive electrochemical membrane of claim 1 , wherein the support layer has a thickness of 50 μm to 5 mm.

10. The reactive electrochemical membrane of claim 1 having a roughness factor of at least 300 (determined based on inner surface area).

11. The reactive electrochemical membrane of claim 1 having a pressure-normalized permeate membrane flux for deionized water between 100 and 8000 L m −2 hr −1 bar −1 , as measured at temperature of 21° C., a cross flow rate of 50 L h −1 , and trans-membrane pressure of 68.9 kPa.

12. A method of preparing the reactive electrochemical membrane of claim 1 , comprising heating a TiO 2 membrane under a H 2 atmosphere to a temperature of 800 to 1500° C.

13. The method of claim 12 , wherein H 2 atmosphere is maintained at a pressure of 0.5 atm to 1.5 atm.

14. The method of claim 12 , wherein the TiO 2 membrane is an asymmetric TiO 2 ultrafiltration membrane.

15. A method of purification and filtration of water comprising
(a) providing a reactor comprising a voltage source having a first terminal and a second terminal, a counter electrode being connected to the first terminal, and the reactive electrochemical membrane of claim 1 being connected to the second terminal,
(b) passing contaminated water through the reactive electrochemical membrane such that the contaminated water is in contact with the counter electrode while applying a voltage between the counter electrode and the reactive electrochemical membrane using the voltage source to remove contaminants; and
(c) removing purified and filtered water from the reactor.

16. The method of claim 15 , wherein the pressure drop across the reactive electrochemical membrane during passing of the contaminated water is less than 2 bar.

17. The method of claim 15 , further comprising electrochemically degrading the contaminants during passing of the contaminated water through the reactor comprising the reactive electrochemical membrane.

18. The method of claim 15 , further comprising submitting the reactive electrochemical membrane to anodic or cathodic electrochemical regeneration after removing the purified and filtered water from the reactor.

19. The method of claim 15 , wherein one or more of contaminants is bacterial or viral pathogen.

20. The method of claim 15 , wherein one or more of contaminants is oxyanions.

Assignees

• Univ Illinois

Inventors

• Chaplin Brian
• Guo Yun
• Jing Yin
• NAYAK Sasmita

Classifications

• C02F2201/4613

  Inversing polarity · CPC title

• C02F2303/04

  Disinfection · CPC title

• B01D69/02

  characterised by their properties · CPC title

• C02F2305/023

  Reactive oxygen species, singlet oxygen, OH radical · CPC title

• B01D69/148

  Organic/inorganic mixed matrix membranes · CPC title