Ultrafiltration tio2 magnéli phase reactive electrochemical membranes

Patent metadata

Field	Value
Publication number	US-2017152163-A1
Application number	US-201615365252-A
Country	US
Kind code	A1
Filing date	Nov 30, 2016
Priority date	Nov 30, 2015
Publication date	Jun 1, 2017
Grant date	—

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 about 1 μm to about 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 about 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 about 80 wt % oxides of titanium, and wherein the oxides of titanium comprise at least about 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 about 95 wt % oxides of titanium.

3 . The reactive electrochemical membrane of claim 1 , wherein the oxides of titanium comprise at least about 85 wt %, or at least about 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 consists essentially of Ti 4 O 7 .

6 . The reactive electrochemical membrane of claim 1 , wherein each of the support layer and the active layer consists essentially 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 about 10 nm to about 1 μm.

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

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

10 . The reactive electrochemical membrane of claim 1 having a roughness factor of at least about 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 about 800 to about 1500° C.

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

• C02F2303/16

  Regeneration of sorbents, filters · CPC title

• C02F2101/163

  Nitrates · CPC title

• C02F1/4608 Primary

  using electrical discharges · CPC title

• C02F2303/04

  Disinfection · CPC title

• B01D69/108

  Inorganic support material · CPC title