Poly(acrylamidoxime) resin for the determination of trace metals in natural waters

Abstract

Fe(III), Mn( 11), Cu(II), Zn(II), Co(II), Ni(II), Hg(II), Pb(II), Cd( 11), and Ag( I ) were sequestered on a poly( acrylamidoxime) resin from laboratory prepared solutions. Recovery of the sequestered metals was achieved by equillbratlon of the resin matrix with either a 1:l HNO,/water mixture, a 1:1 HCVwater mixture, or a 1 M thiosulfate solutlon. Sequestered metals were at least 90 YO recovered with a standard devlatlon of 1 5 %. Regeneration of the resin was achieved by equllibration of the resin with a 3 M ",OH solution after the acid equilibration. The resin was applied for the separation and simultaneous concentration of Fe( HI), Cu( 11), Cd( 11), Pb( 11), and Zn(I1) from seawater and pond water. Metals were removed from the resin by equlllbratlng with a 1:l HCVwater mixture and their concentrations determined by atomic absorption spectrometry. Metal concentrations as determined by the resin method are in good agreement with the values determined directly on samples by either differential pulse polarography or dmerential pulse anodic stripping voltammetry.T h e determination of trace metals in natural waters is important from two different points of view. The first is the inorganic pollution of these waters in which metals have reached concentrations which may be deleterious t o aquatic life and ultimately man. The second consideration is that of micronutrient requirements for various life forms. As pointed out by Hume ( I ) , essential trace elements such as copper, molybdenum, iron, and manganese are present in seawater at very low levels. These are readily depleted resulting in large areas of the ocean which are aquatic equivalents of barren deserts.T h e trace metal content of natural waters must therefore be monitored to determine if the concentrations have reached toxic proportions or have been depleted below the micronutrient requirement levels. The determination of these nanogram-per-gram or sub-nonagram-per-gram levels of metals requires some method of concentration prior to their determinations by existing instrumental methods of analysis ( 2 ) .Metal chelating resins have found widespread application for the concentration of trace metals from natural waters. Muzzarelli and co-workers chemically modified the natural polymer, chitosan, which contains glucosamine functional groups after deacylation (3-6). Fritz et al. synthesized resins containing propylenediaminetetraacetic acid groups (7), nbutylamide groups (8), and hexylthioglycolate groups (9).Vernon and Eccles synthesized and applied N-substituted hydroxylamine (IO) and 8-hydroxyquinoline resins (11).Leyden et al. immobilized alkylamines, dithiocarbamates, and xanthates onto silica gel or controlled-pore glass beads by silylation reactions (12)(13)(14)(15).T h e iminodiacetate containing resin, Chelex-100, is one of the more commonly employed metal chelating resins. Riley and others (16-19) have characterized and applied Chelex-100. Concentration of copper, cadmium, lead, and zinc from sea-'Present address: General Electric Co., Lynn, MA 01910...

Development of Sorbers for the Recovery of Uranium from Seawater. Part 2. The Accumulation of Uranium from Seawater by Resins Containing Amidoxime and Imidoxime Functional Groups

“…Divinylbenzene cross-linked poly( acrylamidoxime) resins were successfully applied to the determination of trace metals in natural waters (18)(19)(20). A condensation polymer containing oxamidoxime functional groups was claimed to separate uranium from artificial seawater (21).…”

Synthesis and chelation properties of Mannich polymers derived from piperazine and some hydroxy benzaldoximes

“…Chelate-forming polymers have found widespread applications in the separation, recovery and monitoring of trace heavy metal ions from aqueous solutions [1][2][3][4][5][6][7][8][9][10][11][12][13]. The use of chelating polymers in radioactive nuclear waste treatment is attracting a great deal of interest.…”

Chelating Resins and Their Applications in the Analysis of Trace Metal Ions

“…Poly(acrylamidoxime) resin has been used for the separation and simultaneous concentration of Fe 3ϩ , Cu 2ϩ , Cd 2ϩ , Pb 2ϩ , and Zn 2ϩ from sea water and pond water (3,4). The resin can be regenerated by equilibrating it with 3 M NH 4 OH solution after the acid equilibration.…”

“…MBT-SG was found to be useful for the analysis of these metal ions present in river and sea water samples. This resin was also used for concentration of Hg 2ϩ , CH 3 Hg ϩ , and C 2 H 5 Hg ϩ from sea water samples at pH 4.0, 4.5, and 5.0, respectively (81). The adsorbed mercury was eluted with 25:1 acetoneHCl mixture or 1% thiourea solution in 0.1 M HCl and determined by atomic absorption spectrometry after reductive vapourization.…”

“…These metals can be eluted selectivity from the column by a ethanol-water mixture, with a mole fraction of 0.5, in the order Co 2ϩ ϳCd 2ϩ Ͼ Cu 2ϩ ϳZn 2ϩ Ͼ Hg 2ϩ . However, Hg 2ϩ was not eluted at all but can be eluted with an aqueous solution of 0.1 M HNO 3 . All the metals were quantitatively recovered with a recovery of almost 100%.…”