Metal ion adsorption properties of a chelating resin containing polyamine-substituted methylphosphonic acid moiety

Metal ions adsorption properties of a chelating resin containing polyamine-substituted methylphosphonic acid moiety of 1.79 mmol/g-Res. (MC-90), were examined. MC-90 showed a good adsorption ability for various metal ions such as U(VI), Cu(II), Hg(II) and Ca in aq. 28 % concentration of sodium chloride soln. in comparison with iminodiacetic acid type chelating resin. One gram of MC-90 adsorbed 1.70 mmol of Cd, Ca or mixed metal ions consisting Cu(II), Ni(II) and Cd. Selection factor (KCaM for each metal ion (M) of pH 3.0 aq. soln. on calcium salt of polyamine-substituted methylphosphonic acid moiety in MC-90 was U(VI) 31.0, Cu(II) 12.3, Hg(II) 1.3, Ca 1.0, Zn 0.5, Fe(III) 0.4, Ni(II) 0.3, Cd 0.2, Cr(III) 0.1 and Na 0.0. The quantity of U(VI) adsorbed on MC-90 at the concentration of 20 mg·dm-3 U(VI), was 0.03 mmol/g-Res. in 30 % H3PO4 aq. soln. and 0.20 mmol/g-Res. in 10 % H2SO4 aq. soln. The adsorbed U(VI) on MC-90 was eluted with an aqueous solution of 1.0 mol·dm-3 Na2S-5.0 mmol·dm-3 NaOH. (author)