Chemically modified rice husk as an effective adsorbent for removal of palladium ions.

Bio-matrix of rice husk and Mobil Composition of Matter No. 41 (MCM-41) was modified with alizarin red S for preconcentration of Pd prior flame atomic absorption spectrometric determination. The prepared bio-matrix (RH@MCM-41@ARS) was characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope, energy dispersive X-ray spectrometer (SEM/EDX) and surface area studies.

Impact of dialyzer membrane flux on metal clearance in hemodialysis patients.

Deficiency of essential trace elements (such as Cu or Zn) and accumulation of potentially toxic trace elements (as Cd or Pb) are both known to have adverse effects in hemodialysis (HD) patients. Up to our knowledge, no studies about the permeability of low and high flux polysulfone membranes on metal ions during hemodialysis are available. Therefore, the aim of the present study was to address this issue.

Mixed Micelle-mediated Extraction and Separation of Scandium from Yttrium and Some Lanthanide Ions.

A simple mixed-micelle mediated extraction was elaborated for the preconcentration and determination of scandium(III) by inductively coupled plasma optical emission spectrometry. Scandium(III) was complexed with Alizarin Red S and cetyltrimethylammonium bromide at pH 3 to form hydrophobic chelates, which could be extracted with Triton X-114 at room temperature (25°C) in the presence of KI as a salting-out electrolyte. The main parameters of the extraction procedure were investigated in regard to the extraction efficiency of scandium(III).

Determination of Cu(2+), Zn(2+) and Pb(2+) in biological and food samples by FAAS after preconcentration with hydroxyapatite nanorods originated from eggshell.

Hydroxyapatite nanorods (HAPNRs) were prepared from recycled eggshell by using precipitation method. The structure of the HAPNRs was physicochemically and morphologically characterized by X-ray diffraction, transmission electron microscopy and Fourier transform infrared spectroscopy. The resulting HAPNRs were used for solid phase extractive preconcentration of Cu(2+), Zn(2+) and Pb(2+) prior to its determination by flame atomic absorption spectrometry.

Selective preconcentration of uranyl ion by silica gel phases modified with chelating compounds as inorganic polymeric ion exchangers.

Four chemically modified chelating silica gel phases (I - IV) with ion exchange groups were tested for their potential capability to selectively bind, extract and preconcentrate uranyl ions (UO(2)(2+)) from different aqueous solutions as well as ore samples. Factors affecting such determination processes were studied and optimized. These included the pH of the contact solution, the mass of the silica gel phase extractant, the stirring time during the application of a static technique and the eluent concentration for desorption of the surface-bound uranyl ion and interfering anions and cations.