Powder-based adsorbents having high adsorption capacities for recovering dissolved metals and methods thereof

Patent metadata

Field	Value
Publication number	US-9327267-B2
Application number	US-201514697711-A
Country	US
Kind code	B2
Filing date	Apr 28, 2015
Priority date	Jul 22, 2011
Publication date	May 3, 2016
Grant date	May 3, 2016

Abstract

A powder-based adsorbent and a related method of manufacture are provided. The powder-based adsorbent includes polymer powder with grafted side chains and an increased surface area per unit weight to increase the adsorption of dissolved metals, for example uranium, from aqueous solutions. A method for forming the powder-based adsorbent includes irradiating polymer powder, grafting with polymerizable reactive monomers, reacting with hydroxylamine, and conditioning with an alkaline solution. Powder-based adsorbents formed according to the present method demonstrated a significantly improved uranium adsorption capacity per unit weight over existing adsorbents.

First claim

The invention claimed is:

1. A method for forming a powder-based adsorbent for the recovery of metal ions from an aqueous solution, the method comprising:
exposing a polymer fiber to ionizing radiation, the polymer fiber defining a mean diameter of less than 15 microns;
co-grafting polymerizable monomers containing nitrile and hydrophilic groups onto the irradiated polymer fiber to form grafted side chains;
reacting the nitrile groups in the grafted side chains with a reagent to convert the nitrile groups into amidoxime groups;
conditioning the polymer fiber with an alkaline solution; and
grinding the co-grafted polymer fiber into polymer granules to form a powder-based adsorbent having grafted side chains with amidoxime groups.

2. The method according to claim 1 wherein the polymer granules have a mean diameter of less than approximately 5 microns.

3. The method according to claim 1 wherein the polymer fibers are polyethylene, polypropylene, or polyacrylonitrile.

4. The method according to claim 1 wherein the reagent is selected from the group consisting of hydroxylamine, hydroxylamine derivatives, hydrazine, hydrazine derivatives, N-methylhydroxylamine, acetohydroxamic acid, N-benzylhydroxylamine hydrochloride, hydroxyurea, tert-butyl n-hydroxycarbamate, sym-diphenylhydrazine, methylhydrazine sulfate, and phenylhydrazine hydrochloride.

5. The method according to claim 1 wherein the polymer fiber includes a non-circular morphology for increasing the fiber surface area.

6. The method according to claim 5 wherein the non-circular morphology includes a trilobial-shaped, gear-shaped, or flower-shaped cross-section.

Assignees

• Ut Battelle Llc

Inventors

• Janke Christopher J
• Dai Sheng
• Oyola Yatsandra

Classifications

• B01J20/28023 Primary

  Fibres or filaments (fibres or filaments in the form of membranes B01J20/28038; B01J20/28007 takes precedence) · CPC title

• C08J9/36

  After-treatment (C08J9/22 takes precedence) · CPC title

• D06M15/31

  of unsaturated nitriles · CPC title

• C08J2433/18

  Homopolymers or copolymers of nitriles · CPC title

• D06M2101/20

  Polyalkenes, polymers or copolymers of compounds with alkenyl groups bonded to aromatic groups · CPC title