Adsorbent precipitated on a carrier, method for producing said adsorbent, and use of said adsorbent

Patent metadata

Field	Value
Publication number	US-9416028-B2
Application number	US-201214239167-A
Country	US
Kind code	B2
Filing date	Aug 2, 2012
Priority date	Aug 17, 2011
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

Abstract

The invention relates to an adsorbent precipitated on a carrier and to a method for producing said adsorbent. The carrier comprises a polymer-based spherical activated charcoal. The adsorbent comprises an inorganic precipitate capable of adsorbing a metal cation or a mixture of metal cations from a liquid, preferably aqueous, medium. The adsorbent precipitated on a carrier is used to remove, for example, Cs + from water containing Cs + , in particular from water contaminated with radiotoxic 137 Cs + .

First claim

The invention claimed is:

1. A method of producing an adsorbent precipitated on a support, which method comprises precipitating an inorganic adsorbent capable of Cs + adsorption from a liquid medium onto a polymer-based spherical activated carbon serving as the support,
wherein the polymer-based spherical activated carbon has been produced from a synthetic polymer and wherein the polymer-based spherical activated carbon has the following characteristics:
a Gurvich total pore volume of not less than 0.5 cm 3 /g, with not less than 50% of the total pore volume being formed by micropores having a pore diameter of not more than 20 Å,
an average pore diameter of not more than 40 Å, and
a BET surface area of not less than 1000 m 2 /g;
wherein the method comprises the following steps:
a) providing the polymer-based spherical activated carbon as the support;
then either steps b1) and c1):
b1) impregnating the support with an aqueous solution containing
(i) hexacyanoferrate(II) or hexacyano-ferrate(III) anions, and
(ii) NH 4 + , Li + , Na + , K + or Rb + ; then

c1) admixing the impregnated support with an aqueous solution of a salt of a di-, tri- or tetravalent metal cation,
so as to obtain the inorganic adsorbent in the form of a complexed hexacyanoferrate(II) or a complexed hexacyanoferrate(III) and precipitated on the support;
or alternatively steps b2) and c2):
b2) impregnating the support with an aqueous solution of a salt of a di-, tri- or tetravalent metal cation,
c2) admixing the impregnated support with an aqueous solution containing
(i) hexacyanoferrate(II) or hexacyano ferrate(III) anions, and
(ii) NH 4 + , Li + , Na + , K + or Rb + ; then

so as to obtain the inorganic adsorbent in the form of a complexed hexacyanoferrate(II) or a complexed hexacyanoferrate(III) and precipitated on the support;

then followed by:
d) washing the support containing the precipitated adsorbent,
e) drying the washed support resulting from step d) and containing the precipitated adsorbent.

2. The method as claimed in claim 1 , wherein the polymer-based spherical activated carbon is a porous polymer-based activated carbon having pores with a minimum average pore diameter of not less than 5 Å.

3. The method as claimed in claim 1 , wherein the divalent metal cation is Cd 2+ , Co 2+ , Cu 2+ , Ni 2+ , Zn 2+ , Sn 2+ or Fe 2+ .

4. The method as claimed in claim 1 , wherein the trivalent metal cation is Cr 3+ or Fe 3+ .

5. The method as claimed in claim 1 , wherein the tetravalent metal cation is Sn 4+ , Ti 4+ or Zr 4+ .

6. A support-precipitated adsorbent obtained by a method as claimed in claim 1 .

7. A method of removing a metal cation or a mixture of metal cations from water, wherein the metal cation or the mixture of metal cations is removed by the support-precipitated adsorbent as claimed in claim 6 .

8. A method of removing Cs + from Cs + -containing water, wherein Cs + is removed by the support-precipitated adsorbent as claimed in claim 6 .

9. A method of producing an adsorbent precipitated on a support, which method comprises precipitating an inorganic adsorbent capable of Cs + adsorption from a liquid medium onto a polymer-based spherical activated carbon serving as the support,
wherein the polymer-based spherical activated carbon has been produced from a synthetic polymer and wherein the polymer-based spherical activated carbon has the following characteristics:
a Gurvich total pore volume of not less than 0.5 cm 3 /g, with not less than 50% of the total pore volume being formed by micropores having a pore diameter of not more than 20 Å,
an average pore diameter of not more than 40 Å, and
a BET surface area of not less than 1000 m 2 /g;
wherein the method comprises the following steps:

a) providing the polymer-based spherical activated carbon as the support;
then either steps b1) and c1):
b1) impregnating the support with an aqueous solution containing
(i) hexacyanoferrate(II) or hexacyano-ferrate(III) anions, and
(ii) NH 4 + , Li + , Na + , K + or Rb + ; then

c1) admixing the impregnated support with an aqueous solution of a salt of a di-, tri- or tetravalent metal cation,
so as to obtain the inorganic adsorbent in the form of a complexed hexacyanoferrate(II) or a complexed hexacyanoferrate(III) and precipitated on the support;
wherein the divalent metal cation is Cd 2+ , Co 2+ , Cu 2+ , Ni 2+ , Zn 2+ , Sn 2+ , or Fe 2+ , wherein the trivalent metal cation is Cr 3+ or Fe 3+ and wherein the tetravalent metal cation is Sn 4+ , Ti 4+ , or Zr 4+ ;
or alternatively steps b2) and c2):
b2) impregnating the support with an aqueous solution of a salt of a di-, tri- or tetravalent metal cation,
c2) admixing the impregnated support with an aqueous solution containing
(i) hexacyanoferrate(II) or hexacyano ferrate(III) anions, and
(ii) NH 4 + , Li + , Na + , K + or Rb + ; then

so as to obtain the inorganic adsorbent in the form of a complexed hexacyanoferrate(II) or a complexed hexacyanoferrate(III) and precipitated on the support;
wherein the divalent metal cation is Cd 2+ , Co 2+ , Cu 2+ , Ni 2+ , Zn 2+ , Sn 2+ , or Fe 2+ , wherein the trivalent metal cation is Cr 3+ or Fe 3+ and wherein the tetravalent metal cation is Sn 4+ , Ti 4+ , or Zr 4+ ;

then followed by:
d) washing the support containing the precipitated adsorbent,
e) drying the washed support resulting from step d) and containing the precipitated adsorbent.

Assignees

• Schrage Christian
• Giebelhausen Jann-Michael
• Fichtner Sven
• Bluecher Gmbh

Inventors

• Schrage Christian
• Giebelhausen Jann-Michael
• Fichtner Sven

Classifications

• B01J20/0292

  Phosphates of compounds other than those provided for in B01J20/048 · CPC title

• B01J20/3071

  Washing or leaching · CPC title

• G21F9/12

  by absorption; by adsorption; by ion-exchange · CPC title

• B05D1/36

  Successively applying liquids or other fluent materials, e.g. without intermediate treatment · CPC title

• B01J20/0211

  Compounds of Ti, Zr, Hf · CPC title