Sandra Villegas

Metal ion uptake properties of acrylamide derivative resins

Completely water insoluble resins containing different ligand groups were synthesized by radical polymerization in solution. The yield was higher than 78%. The resins were characterized by FT-IR spectroscopy and thermal analysis. The retention properties at different pH were investigated by a batch method. Metal ions studied were: Cu(II), Cd(II), Zn(II), Hg(II), Pb(II), Cr(III), and U(VI). The retention properties were also tested under competitive conditions and were found to depend strongly on the pH. Elution of the metal ions was investigated in acid and basic media.

Adsorption behavior of metal ions by amidoxime chelating resin

The adsorption properties of poly(acrylamidoxime) chelating resin for Cu(II), Cd(II), Hg(II), Zn(II), Pb(II), Cr(III), and U(VI) are investigated by the batch technique. Based on the research results of the binding capacity effect of the pH value on sorption kinetic experiments, it is shown that this resin has higher binding capacity to uranyl ions, fast kinetics, and very good selectivity from binary metal ion mixtures with Cu(II) and Pb(II). The uranyl ion sorption strongly depends on the pH value of the solution. The highest value of 99% is at pH 5, but at pH 1 there is no retention. The adsorbed UO can be eluted by sulfuric acid and sodium carbonate.

REMOVAL OF METAL IONS WITH IMPACT ON THE ENVIRONMENT BY WATER-INSOLUBLE FUNCTIONAL COPOLYMERS: SYNTHESIS AND METAL ION UPTAKE PROPERTIES

The crosslinked resins poly(4-acryloylmorpholine-co-4-vinyl pyridine) P(AMo- VPy), poly(N-(3-dimethylamino)propylmethacrylamide-co-4-vinyl pyridine) P(NDAPA-VPy), and poly((3-dimethylamino)propylacrylate-co-4-vinyl pyridine) P(DAPA-VPy) were obtained by radical polymerization. The resins were completely insoluble in water. The uptake metal ion properties are studied by batch equilibrium procedure for the following metal ions: silver(I), copper(II), cadmium(II), zinc(II), lead(II), mercury(II), chromium(III), and aluminum(III). P(AMo-VPy) resin shows a lower metal ion affinity than P(DAPA-VPy), except for Hg(II) which is retained in almost 100 % at pH 2. At pH 5, the resin shows the higher affinity for Ag(I) (80%) and Cu(II) (60%) but it is very low for Zn(II) and Cr(III). The polymer ligand metal ion equilibrium is achieved during the first 20 min. By changing the pH is possible to remove between 50 % and 70 % of Cd(II) and Cu(II) ions by using (1 M, 4 M) HClO4 and (1 M, 4 M) HNO3

BINDING OF URANYL IONS BY WATER-INSOLUBLE POLYMERS CONTAINING MULTILIGAND GROUPS

ABSTRACT The crosslinked resins poly(N-(3-dimethylamino)propylmethacrylamide) P(NDAPA), poly((3-dimethylamino)propylacrylate)P(DAPA), poly(4-acryloylmorpholine-co-acrylic acid) P(AMo-AA), poly(N-(3-dimethylamino)propylmethacrylamide-co-4-vinyl pyridine) P(NDAPA-VPy) and poly((3-dimethylamino)propylacrylate-co-acrylic acid) P(DAPA-AA), poly(N-(3-dimethylamino)propylmethacrylamide-co-acrylic acid) P(NDAPA-AA) were obtained by radical polymerization. These resins were completely insoluble in water. The uptake metal ion properties were studied by batch equilibrium procedure for copper(II) and uranyl ions.Keywords: resin; radical polymerization; metal ions; polymer-metal complexesP(AMo-AA): AMo (0.04 mole, 5 mL), AA (0.043 mole, 3 mL), DVB (0.0035 mole, 0.5 mL) and AIBN (0.00039 mole, 0.0651 g) (Merck) in 8 mL of dry toluene. Yield = 95.0 %. P(NDAPA-AA): NDAPA (0.0276 mole, 5 mL), AA (0.029 mole, 2 mL), MBA (0.0021 mole, 0.3461 g) and AP (0.00027 mole, 0.0605 g) in 7 mL of water. Yield = 97.0 %.P(NDAPA-VPy): NDAPA (0.0276 mole, 5 mL), VPy (0.0278 mole, 3 mL), MBA (0.0022 mole, 0.3450 g) and AP (0.00031 mole, 0.0697 g) in 8 mL of water. Yield = 87.0 %. P(DAPA-AA): DAPA (0.0295 mols, 5 mL), AA (0.0292 mole, 2 mL), MBA (0.0023 mole, 0.3659 g) and AP (0.00027 mole, 0.0618 g) in 7 mL of water. Yield = 99.0%. The polymerization mixtures were kept under nitrogen at 70oC for 8 h (see Scheme 1). Then methanol was added and the resin was removed from the flask, filtered and washed with abundant water. The resin was dried under vacuum at 40oC and then milled and sized by screening. The fraction with mesh size in the range of 250-500 mm was chosen.Scheme 1. Synthesis and structure of the resinsResin – metal ion uptakeThe effect of the pH on the metal ion retention properties was studied by batch equilibrium procedure. These batch metal uptake experiments were carried out using the standard metal salts Cu(NO