Buffer-free process cycle for CO2 sequestration and carbonate production from brine waste streams with high salinity

Patent metadata

Field	Value
Publication number	US-11040898-B2
Application number	US-201916431300-A
Country	US
Kind code	B2
Filing date	Jun 4, 2019
Priority date	Jun 5, 2018
Publication date	Jun 22, 2021
Grant date	Jun 22, 2021

Abstract

A method includes: (1) using a chelating agent, extracting divalent ions from a brine solution as complexes of the chelating agent and the divalent ions; (2) using a weak acid, regenerating the chelating agent and producing a divalent ion salt solution; and (3) introducing carbon dioxide to the divalent ion salt solution to induce precipitation of the divalent ions as a carbonate salt. Another method includes: (1) combining water with carbon dioxide to produce a carbon dioxide solution; (2) introducing an ion exchanger to the carbon dioxide solution to induce exchange of alkali metal cations included in the ion exchanger with protons included in the carbon dioxide solution and to produce a bicarbonate salt solution of the alkali metal cations; and (3) introducing a brine solution to the bicarbonate salt solution to induce precipitation of divalent ions from the brine solution as a carbonate salt.

First claim

What is claimed is:

1. A method comprising:
combining water with carbon dioxide to produce a carbon dioxide solution;
introducing an ion exchanger to the carbon dioxide solution to induce exchange of alkali metal cations included in the ion exchanger with protons included in the carbon dioxide solution and to produce a bicarbonate salt solution of the alkali metal cations; and
introducing a brine solution to the bicarbonate salt solution to induce precipitation of divalent ions from the brine solution as a carbonate salt.

2. The method of claim 1 , wherein the ion exchanger is a heterogeneous ion exchanger.

3. The method of claim 2 , wherein the heterogeneous ion exchanger is a polymer-supported ion exchanger.

4. The method of claim 2 , wherein the heterogeneous ion exchanger is a silicate mineral to support ion exchange reaction.

5. The method of claim 2 , further comprising recovering the heterogeneous ion exchanger by filtration.

6. The method of claim 5 , further comprising regenerating the heterogeneous ion exchanger by exposing the heterogeneous ion exchanger to an alkali metal cation solution.

Assignees

• Univ California

Inventors

• Sant Gaurav
• Wei Zongsu
• Wang Bu
• La Plante Erika Callagon
• Simonetti Dante

Classifications

• C02F2303/16

  Regeneration of sorbents, filters · CPC title

• C02F2001/425

  using cation exchangers · CPC title

• C02F9/00

  Multistage treatment of water, waste water or sewage · CPC title

• C02F1/68

  by addition of specified substances, e.g. trace elements, for ameliorating potable water (medicinal water A61K) · CPC title

• C02F1/66

  by neutralisation; pH adjustment (for degassing C02F1/20; using ion-exchange C02F1/42; for flocculation or precipitation of suspended impurities C02F1/52; for removing dissolved compounds C02F1/58) · CPC title