Materials and methods for the selective recovery of multivalent products

Patent metadata

Field	Value
Publication number	US-9878321-B2
Application number	US-201615094930-A
Country	US
Kind code	B2
Filing date	Apr 8, 2016
Priority date	Apr 8, 2015
Publication date	Jan 30, 2018
Grant date	Jan 30, 2018

Abstract

Described herein are processes and apparatus for the high purity and high concentration recovery of multivalent products via continuous ion exchange from aqueous solutions for further down-stream purification.

First claim

What is claimed is:

1. A method of recovering multivalent products from aqueous solutions using continuous ion exchange comprising:
(a) adsorbing the multivalent product comprising diamine chosen from putrescine, cadaverine, hexamethylenediamine, and heptamethylenediamine, principally as a divalent species onto an ion exchange resin;
(b) converting the adsorbed multivalent product to principally the monovalent valence state;
(c) concentrating the multivalent product through re-adsorption onto the ion exchange resin; and
(d) eluting the multivalent product.

2. The method of claim 1 , wherein (1) impurities are selectively desorbed and (2) the adsorbed multivalent product is converted to principally the monovalent state by feeding a base or an acid at a concentration that allows the pH of the aqueous solution discharged from the resin to be approximately the pK a2 for cationic divalent products and to be approximately the pK a1 for anionic divalent products.

3. The method of claim 2 , wherein the multivalent product at a pH of approximately a first equivalence point is recycled to the ion exchange resin and concentrated through re-adsorption.

4. The method of claim 1 , wherein (1) impurities are selectively desorbed and (2) the adsorbed multivalent product is converted to principally the monovalent state by recycling the multivalent product in principally the zero valence state, concentrating the multivalent product though re-adsorption.

5. The method of claim 1 , wherein the multivalent product is eluted from the ion exchange resin with ammonia, ammonium bicarbonate and/or ammonium carbonate.

6. The method of claim 3 or claim 5 , where the eluted multivalent product is fed to a steam stripper, adjusting the pH of the multivalent product to approximately the first equivalence point.

7. The method of claim 4 or claim 5 , where the eluted multivalent product is fed to a steam stripper, adjusting the pH of the multivalent product to where the multivalent product is principally in the zero valence state.

8. The method of claim 6 , where a fraction of the multivalent product recovered from the steam stripper is recycled to the ion exchange resin and concentrated through re-adsorption.

9. The method of claim 1 , further comprising at least one wash step after one or more of steps (a), (b), (c), and (d) using an aqueous solution.

10. The method of claim 7 , where a fraction of the multivalent product recovered from the steam stripper is recycled to the ion exchange resin and concentrated through re-adsorption.

Assignees

• Invista North America Sarl
• Invista North America S Á R L

Inventors

• Kamionka Mariusz
• Conradie Alex

Classifications

• B01J49/60

  Cleaning or rinsing ion-exchange beds · CPC title

• C02F2101/38

  containing nitrogen · CPC title

• B01J49/05 Primary

  of fixed beds · CPC title

• B01J39/05

  in the strongly acidic form · CPC title

• C07C209/86

  Separation · CPC title