Desalination of high chloride salt absorbed porous beads

Patent metadata

Field	Value
Publication number	US-2023321630-A1
Application number	US-202218061399-A
Country	US
Kind code	A1
Filing date	Dec 2, 2022
Priority date	Apr 8, 2022
Publication date	Oct 12, 2023
Grant date	—

Abstract

A method of recovering desalinated activated alumina (AA) beads from a composition including salt laden (high salt absorbed) activated alumna (AA) beads and free anions and free cations, comprising the step of electrodialysis of the composition to reduce salt content of the activated alumina (AA) beads to produce a stream comprising the desalinated activated alumina (AA) beads.

First claim

1 . A method of recovering desalinated activated alumina (AA) beads from a composition comprising salt laden activated alumna (AA) beads and free anions and free cations, wherein the salt of the salt laden activated alumna (AA) beads comprises a chloride salt, comprising:
electrodialysis of the composition to reduce chloride salt content of the activated alumina (AA) beads to produce a stream comprising the desalinated activated alumina (AA) beads, wherein the activated alumina (AA) beads have a D50 median particle size of 0.5 mm to 5 mm.

2 . The method of claim 1 ,
wherein the salt laden activated alumna (AA) beads may have greater than greater than 5,000 ppm, by weight chloride anion on a dry basis; and wherein the desalinated activated alumna (AA) beads may have less than 5,000 ppm, by weight chloride anion on a dry basis.

3 . The method of claim 1 ,
wherein the composition comprises a mixture of the salt laden activated alumina (AA) beads, liquid water and electrolyte, wherein the chloride salt forms the free anions and free cations in the water, wherein the cations comprise alkali metal ions and the anions comprise chloride ions and optionally potassium ions; subjecting the mixture of activated alumina, liquid water, and electrolyte to the electrodialysis in an electrodialysis device by running an electric current through the mixture of activated alumina, liquid water, and electrolyte to remove the anions and the cations from the mixture to produce the desalinated activated alumina having reduced concentration of chloride salt absorbed on the activated alumina relative to concentration of chloride salt absorbed on the salt laden activated alumina prior to the electrodialysis, wherein the electrodialysis device comprises an anode and a cathode; and separating the desalinated activated alumina beads from liquid of the mixture; optionally repeating the process to reuse the liquid to extract chloride from an additional batch of salt laden activated alumina (AA) beads.

4 . The method of claim 3 , wherein the electrodialysis device comprises a diluate chamber and a concentrate chamber between the cathode and the anode;
wherein the salt laden activated alumina are placed in the diluate chamber, wherein the water and the electrolyte are placed in the diluate chamber and the concentrate chamber.

5 . The method of claim 3 , wherein the electrodialysis device comprises a diluate chamber containing the anode and a concentrate chamber containing the cathode;
wherein the chloride salt laden activated alumina beads are placed in the diluate chamber, wherein the water and the electrolyte are placed in the diluate chamber and the concentrate chamber.

6 . The method of claim 3 ,
wherein anolyte comprising the salt laden activated alumina beads and water is added into the electrodialysis device; wherein catholyte comprising the water is added into the electrodialysis device; wherein the electrolyte, for example tetraethylammonium tetrafluoroborate, is added to the salt laden activated alumina beads and the water in the electrodialysis device.

7 . The method of claim 6 , wherein temperature in the anolyte is in a range from about 50 to about 100° C.

8 . The method of claim 1 , wherein the electrodialysis is done using an electrodialysis cell with a cation exchange membrane between an anode and a cathode.

9 . The method of claim 1 , wherein the electrodialysis is done using an electrodialysis cell without a cation exchange membrane between an anode and a cathode.

10 . The method of claim 3 , wherein the electrodialysis device comprises at least one electrodialysis cell configured so that a cation exchange membrane separates at least one anolyte product region, containing the desalinated activated alumina beads, from a catholyte region.

11 . The method of claim 1 , wherein the activated alumina beads have a volume mean diameter, or a mean length of particle size of 0.5 mm to 5 mm.

12 . The method of claim 1 , wherein the electrodialysis is performed at a current density in the range from about 1 to about 10 kA/m 2 .

13 . The method of claim 3 , wherein material of the cathode is steel, nickel, graphite, titanium, coated titanium or activated nickel.

14 . The method of claim 3 , wherein material of the anode is lead, graphite, titanium, coated titanium, lead oxides, tin oxide, tantalum or titanium, or combinations thereof.

15 . The method of claim 1 , wherein the chloride salt laden activated alumina beads are pre-wetted before the electrodialysis in water, before being added to the electrodialysis device.

16 . The method of claim 3 , wherein the alkali metal ions are collected as an alkali metal hydroxide-containing aqueous catholyte, and wherein the chloride ions form hydrochloric acid and/or chlorine gas.

17 . A method for making a gypsum board comprising:
recovering desalinated activated alumina (AA) beads from a composition comprising the salt laden activated alumna (AA) beads and free anions and free cations by the method of claim 1 ; and treating a salt-containing gypsum source comprising salt-containing gypsum powder particles with the desalinated activated alumina (AA) beads, said treating comprising: mixing the desalinated activated alumina (AA) beads, which have an absence of moisture or up to 30% free moisture, with the salt-containing gypsum powder particles, which contain 5-30 wt. % of free moisture, for a time in a range of 5 minutes to 5 hours, at a mix ratio of the chloride salt absorbing beads to the salt-containing gypsum powder particles in a range 5 to 50 parts by weight beads to 100 parts by weight salt-containing gypsum powder particles on a moisture inclusive basis, to transfer chloride salt from the salt-containing gypsum powder particles to the desalinated activated alumina (AA) beads to produce a mixture of salt laden activated alumina (AA) beads and treated gypsum powder particles, wherein the salt laden activated alumina (AA) beads are all larger in particle size than the treated gypsum powder particles; wherein the salt-containing gypsum powder particles comprise at least 80 wt. % calcium sulfate dihydrate on a dry basis, wherein the salt-containing gypsum powder particles comprise greater than 300 parts by weight chloride anion per 1,000,000 parts by weight said salt-containing gypsum powder particles on a dry basis, wherein the salt-containing gypsum powder particles have a D50 median particle size of 10 to 100 microns, wherein the desalinated activated alumina (AA) beads have a D50 median particle size of 0.5 mm to 5 mm, and after said mixing of the desalinated activated alumina (AA) beads with the salt-containing gypsum powder particles, drying the mixture of the salt laden activated alumina (AA) beads and the treated gypsum powder particles and separating the treated gypsum powder particles from the salt laden activated alumina (AA) beads to recover the treated gypsum powder particles and recover the salt laden activated alumina (AA) beads; calcining the recovered treated gypsum powder particles to make stucco comprising calcium sulfate hemihydrate; mixing the stucco with water to form an aqueous gypsum slurry comprising the calcium sulfate hemihydrate; depositing the aqueous gypsum slurry on a surface to form a layer of the aqueous gypsum slurry; allowing the deposited layer of the aqueous gypsum slurry to set to form a layer comprising set gypsum; cutting and drying the layer comprising set gypsum to make the gypsum board comprising the set gypsum as a core layer.

18 . A gypsum board made

Assignees

• United States Gypsum Co

Inventors

• Li Qinghua
• Chen Xiaoyan

Classifications

• B01J20/3441 Primary

  Regeneration or reactivation by electric current, ultrasound or irradiation, e.g. electromagnetic radiation such as X-rays, UV, light, microwaves · CPC title

• C01F7/021

  After-treatment of oxides or hydroxides · CPC title

• B01J20/3433 Primary

  of sorbents or filter aids other than those covered by B01J20/3408 - B01J20/3425 · CPC title

• B01J20/08

  comprising aluminium oxide or hydroxide; comprising bauxite · CPC title

• B01J20/28016

  Particle form · CPC title