Novel extractant impregnated resin for preconcentration and determination of uranium from environmental samples

A novel method based on impregnation of Amberlite XAD-4 with extractant isonitroso-4-methyl-2-pentanone (IMP) has been developed for U6 + extraction and determination in various samples. The prepared extractant im- pregnated resin (EIR) sorbent was characterized by the field emission scanning electron microscope. The sorbent was packed in a glass column and investigated for various parameters such as pH, eluent, sample and eluent flow rates to optimize sorption desorption conditions for U6+. U6+ is quantitatively determined at pH 4 with flow rate 2 mL/min which showed recovery of 98.9%. The sorption behaviour of U6 + by EIR was also studied using different equilibrium isotherms and kinetic models and the experimental data confirmed that it follows Freundlich iso- therm and Weber-Morris pore diffusion kinetic model. The investigation of foreign ions influence on U6+ sorp- tion showed least interference and thus, facilitated its extraction and determination in Uranmicrolite (leachate) ore tailing, synthetic mixtures and spiked water samples. The detection limit was 0.41 μg/L while the limit of quantification as 1.35 μg/L made the method quite accurate

Extractive spectrophotometric determination of nickel (II) using 4-methyl 2,3-pentanedione dioxime (H₂MPDDO)

581-584A new analytical reagent, 4-methyl 2,3-pentanedione dioxime (H2MPDDO), is proposed for the extraction and spectrophotometric determination of nickel. H2MPDDO reacts with nickel (II) to give yellow coloured complex, which can be quantitatively extracted into chloroform at pH 9.0. The organic extract shows maximum absorption at 370 nm where absorption due to a similarly prepared reagent blank is negligible. The Beer’s law is followed in the concentration range 0.5-10 mg/ml of nickel (II). The molar absorptivity and Sandell’s sensitivity of Ni (II)-(H2MPDDO)2 complex are 3.039x103 l/mol/cm and 0.0192 mg/ml/cm2, respectively. The stoichiometry of extracted species was found to be 1:2 (M:L). The proposed method is rapid, sensitive, reproducible and accurate, and has been satisfactorily applied for the determination and separation of nickel in synthetic mixtures and spent catalyst samples