Separation of metal ions using a polymeric reversed-phase column and a Methylthymol Blue containing mobile phase

Separation behavior of U(VI) and Th(IV) on a cation exchange column using 2,6‐pyridine dicarboxylic acid as a complexing agent and its application for the rapid separation and determination of U and Th by ion chromatography

“…Using 2,6‐pyridine dicarboxylic acid (PDCA) as a chelating substrate, many high‐performance chelation ion chromatography (HPCIC) methods were also reported for the determination of uranium in various samples including seawater and sediment matrices 8–11. Th(IV), Fe(III) and REE were eluted together at the void volume peak while stronger U(VI)‐PDCA complex was retained on the column.…”

Chemical Processes in Marine Environments

“…The barium separation and determination at mg rl concentration in 1600 mg rl Ca samples with neutral hydrophobic resin (PS-DVB), precedingly impregnated with methylthymol blue (3,Ndi(carboxymethyl)aminomethyllthymol-sulfonephthalein) coupled with an acid elution (0.5 M KN03 + 0.5 M lactic acid) and UV detection by post-column reaction (4-(2-pyridylazo)-resorcinol + ZnEDTA) (Paull et al 1994a) was successfully achieved showing a detection limit of 3 flg rl for Ba and Sr, as well as Sr and Ca separation was optimized in milk powder analysis with a phthalein purple (0-cresolphthalein-3',3"bis-methyleneiminodiacetic acid) impregnated column (Jones et al1994). Finally Haddad et al developed the dynamic chelating chromatography (Paull et al 1998) by studying a procedure where a polymeric reversed-phase was dynamically coated with the methylthymol blue (MTB) ligand. The stationary phase enables Ca and Mg removal during the sample oncolumn pre concentration at pH 6 and the separation and determination of Zn, Pb, Ni and Cu with a step-gradient pH elution.…”

Chelation ion chromatography of metal ions using an ODS reversed-phase column and a mobile phase containing methylthymol blue

“…Preliminary results from investigations into the use of a methylthymol blue (MTB) containing mobile phase used with a polystyrene±divinylbenzene (PS±DVB) based reversed-phase column, for the chelation ion chromatography of certain transition and heavy metals have recently been reported [10]. The method was applied to the separation of Mn(II), Zn(II), Cd(II) and Pb(II) in the presence of excess concentrations of matrix metals.…”