SORBENT FOR BINDING METALS AND PRODUCTION THEREOF
The present invention relates to a sorbent which is suitable for binding metals from solutions, the production of a corresponding sorbent as well as the use of the sorbent for binding metals from solutions.
1 . Sorbent, comprising a porous support material coated with an amino group-containing polymer, wherein the concentration of the amino groups of the sorbent determined by titration is at least 600 μmol/mL, based on the total volume of the sorbent.
2 . Sorbent according to claim 1 , wherein the ratio of the mass of the amino group-containing polymer to the total volume of the pores of the porous support material is greater than or equal to 0.1 g/mL.
3 . Sorbent according to claim 1 , wherein the pore volume of the porous support material lies in the range from 30 to 90 vol. %, based on the total volume of the porous support material.
4 . Sorbent according to claim 1 , wherein the porous support material has an average pore size in the range from 6 nm to 400 nm.
5 . Sorbent according to claim 1 , wherein the porous support material comprises an organic polymer, an inorganic material or a composite material of organic polymer and inorganic material.
6 . Sorbent according to claim 1 , wherein the amino group-containing polymer is a polyalkylamine.
7 . Sorbent according to claim 1 , wherein the amino group-containing polymer is a crosslinked polymer and/or is present not covalently linked with the porous support material.
8 . Process for the production of a sorbent, which comprises the following steps:
(a) providing a porous support material;
(b) applying an amino group-containing polymer onto the porous support material by a pore filling method;
(c) removing solvent used in the pore filling method;
(d) repeating steps (b) and (c); and
(e) crosslinking of the amino group-containing polymer.
9 . Process according to claim 8 , wherein the steps (b) and (c) are repeated before the step (e) sufficiently often that the concentration of the amino groups of the sorbent determined after step (e) by titration is at least 600 μmol/mL, based on the total volume of the sorbent.
10 . Process according to claim 8 , wherein the ratio of the mass of the amino group-containing polymer to the total volume of the pores of the porous support material after step (d) is greater than or equal to 0.1 g/mL.
11 . Process according to claim 8 , wherein step (c) is performed at a temperature in the range from 40 to 80° C. and/or a pressure in the range from 0.01 bar to 1 bar.
12 . Process according to claim 8 , wherein the concentration of the amino group-containing polymer in the solvent used for the pore filling method in step (b) lies in the range from 5 g/L to 200 g/L.
13 . Process according to claim 8 , wherein in a step (f) an organic residue which has the nature of a Lewis base is bound onto the amino group-containing polymer.
14 . Sorbent which is obtainable according to a process of claim 8 .
15 . A process for binding metals from solutions, comprising contacting a solution containing metal with a sorbent, wherein the sorbent is a porous support material coated with an amino group-containing polymer, wherein the concentration of the amino groups of the sorbent determined by titration is at least 300 μmol/mL.