Method of purifying waste hydrochloric acid

Patent metadata

Field	Value
Publication number	US-2020270132-A1
Application number	US-201715774915-A
Country	US
Kind code	A1
Filing date	Oct 25, 2017
Priority date	Nov 9, 2016
Publication date	Aug 27, 2020
Grant date	—

Abstract

The present invention relates to a method of purifying waste hydrochloric acid, and more particularly, to a method of purifying waste hydrochloric acid which includes preparing an extraction solution by dissolving an extractant in an organic solvent (S1), extracting metallic components with the organic solvent by adding the extraction solution to the waste hydrochloric acid (S2), separating a waste hydrochloric acid layer and the organic solvent containing the metallic components (S3), and obtaining purified hydrochloric acid by recovering the separated (fractionated) waste hydrochloric acid layer (S4), wherein the extractant is used in an amount of 40 moles or more based on 1 mole of iron (Fe) included in the waste hydrochloric acid, and the waste hydrochloric acid and the extraction solution are mixed in a volume ratio of 1:0.1 to 1:1.

First claim

1 . A method of purifying waste hydrochloric acid, the method comprising steps of:
preparing an extraction solution by dissolving an extractant in an organic solvent (S1); extracting metallic components in waste hydrochloric acid with the organic solvent by adding the extraction solution to the waste hydrochloric acid (S2); separating a waste hydrochloric acid layer and the organic solvent containing the metallic components (S3); and obtaining purified hydrochloric acid by recovering the separated (fractionated) waste hydrochloric acid layer (S4), wherein an amount of the extractant used is 40 moles or more based on 1 mole of an iron (Fe) ion component of the metallic components contained in the waste hydrochloric acid, and the waste hydrochloric acid and the extraction solution are mixed in a volume ratio of 1:0.1 to 1:1.

2 . The method of claim 1 , further comprising a step of measuring a concentration of the iron (Fe) ion component of the metallic components contained in the waste hydrochloric acid (S0), before the preparing of the extraction solution.

3 . The method of claim 1 , wherein the organic solvent comprises at least one solvent selected from the group consisting of an aromatic hydrocarbon solvent, an aliphatic hydrocarbon solvent, and an alcohol.

4 . The method of claim 3 , wherein the aromatic hydrocarbon solvent comprises at least one selected from the group consisting of toluene and xylene,
the aliphatic hydrocarbon solvent comprises at least one alicyclic hydrocarbon solvent selected from the group consisting of methyl cyclohexane and cyclohexane, or a linear hydrocarbon solvent having 6 to 20 carbon atoms, and the alcohol comprises a monovalent alcohol having 6 to 20 carbon atoms.

5 . The method of claim 1 , wherein the extractant comprises at least one selected from the group consisting of trioctylamine, methyl isobutyl ketone, trialkylphosphine oxide, and tributyl phosphate.

6 . The method of claim 5 , wherein the extractant comprises at least one selected from the group consisting of trioctylamine and methyl isobutyl ketone.

7 . The method of claim 6 , wherein the extractant is trioctylamine.

8 . The method of claim 1 , wherein an amount of the extractant used is in a range of 40 moles to 60 moles based on 1 mole of the iron (Fe) ion component.

9 . The method of claim 8 , wherein the amount of the extractant used is in a range of 40 moles to 50 moles based on 1 mole of the iron (Fe) ion component.

10 . The method of claim 1 , wherein the extracting (S2) is performed for 20 seconds to 60 seconds at atmospheric temperature while stirring a mixed solution of the waste hydrochloric acid and the extraction solution at a speed of 200 rpm to 600 rpm.

11 . The method of claim 1 , wherein the separating (S3) is performed within 20 seconds.

12 . The method of claim 1 , after the obtaining of the purified hydrochloric acid (S4), further comprising steps of:
removing the residual metallic components in the organic solvent by adding distilled water to the separated organic solvent containing the metallic components (S5); separating a water layer and the organic solvent having the metallic components removed therefrom (S6); and recovering the separated organic solvent and water layer, respectively (S7).

13 . The method of claim 12 , wherein the organic solvent and the distilled water are mixed in a volume ratio of 1:1.

14 . The method of claim 12 , wherein the removing (S5) is performed for 20 seconds to 60 seconds at atmospheric temperature while stirring a mixed solution of the separated organic solvent and the distilled water at a speed of 200 rpm to 600 rpm.

15 . The method of claim 12 , wherein the separating (S6) is performed within 20 seconds.

Assignees

• Lg Chemical Ltd

Inventors

• Eom Hee Jun
• Lee Dong Chul
• Kim Yeon Yi
• Choi Jung Ho

Classifications

• B01D11/0492 Primary

  Applications, solvents used · CPC title

• B01D11/0292 Primary

  Treatment of the solvent · CPC title

• B01D11/0288

  Applications, solvents · CPC title

• C01P2006/80

  Compositional purity · CPC title

• B01D11/0484

  Controlling means · CPC title