Bromide recovery from aqueous streams

Patent metadata

Field	Value
Publication number	US-9963359-B2
Application number	US-201414763700-A
Country	US
Kind code	B2
Filing date	Jan 27, 2014
Priority date	Jan 27, 2013
Publication date	May 8, 2018
Grant date	May 8, 2018

Abstract

The invention relates to a process for recovering bromide from a halide-containing aqueous stream, comprising the steps of: providing a feed of halide-containing aqueous stream; contacting an anion-exchange resin with said feed, to form halide-loaded resin; treating said halide-loaded resin with a regenerant and subsequently with a rinse to produce, in succession, a chloride-rich solution, a mixed chloride/bromide solution, a bromide-rich solution and an essentially halide-free solution; directing said mixed chloride/bromide solution to said feed; processing said bromide-rich solution to recover one or more bromide products; and utilizing said essentially halide-free solution for regenerant dilution and/or rinsing of said resin. An apparatus for carrying out the process is also disclosed.

First claim

The invention claimed is:

1. A process for recovering bromide from a halide-containing aqueous stream, comprising the steps of:
providing a feed of halide-containing aqueous stream; contacting an anion-exchange resin with said feed, to form halide-loaded resin;
treating said halide-loaded resin with a regenerant and subsequently with a rinse to produce, in succession, a chloride-rich solution, a mixed chloride/bromide solution, a bromide-rich solution and an essentially halide-free solution; directing said mixed chloride/bromide solution to said feed; processing said bromide-rich solution to recover one or more bromide products; and
utilizing said essentially halide-free solution for regenerant dilution and/or rinsing of said resin.

2. A process according to claim 1 , wherein the anion-exchange resin is a strong base anion exchange resin with a total capacity of not less than 3.00 meq/gram expressed on a dry weight basis and a selectivity constant bromide-chloride of not less than 2.5.

3. A process according to claim 1 , wherein the regenerant comprises a solution of sulfuric acid.

4. A process according to claim 3 , wherein the mixed chloride/bromide solution is treated to increase its pH and remove sulfate therefrom before said mixed chloride/bromide solution is returned to, and combined with, the feed stream.

5. A process according to claim 4 , wherein a base selected from the group consisting of calcium carbonate and calcium hydroxide is added to the mixed chloride/bromide solution, followed by the separation of calcium sulfate precipitate from said solution.

Assignees

• Bromine Compounds Ltd

Inventors

• Korngold Emanuel
• Cohen Mordechai
• Freiberg Mira Bergstein
• Rubin Sharon Krumbein

Classifications

• C02F2303/185

  The treatment agent being halogen or a halogenated compound · CPC title

• C02F1/42 Primary

  by ion-exchange (ion-exchange in general B01J) · CPC title

• C02F2303/16

  Regeneration of sorbents, filters · CPC title

• C02F2001/422

  using anionic exchangers · CPC title

• C02F2101/12

  Halogens or halogen-containing compounds · CPC title