On the Potential of a Poly(vinylidenefluoride--hexafluoropropylene) Polymer Inclusion Membrane Containing Aliquat 336 and Dibutyl Phthalate for V(V) Extraction from Sulfate Solutions.

A polymer inclusion membrane (PIM) composed of 50 wt% base polymer poly(vinylidenefluoride--hexafluoropropylene), 40 wt% extractant Aliquat 336, and 10 wt% dibutyl phthalate as plasticizer/modifier provided the efficient extraction of vanadium(V) (initial concentration 50 mg L) from 0.1 M sulfate solutions (pH 2.5).

Multivariate Optimization of a Functionalized SBA-15 Mesoporous Based Solid-Phase Extraction for U(VI) Determination in Water Samples.

A solid-phase extraction based on a functionalized SBA-15, with the Schiff base ligand, ethylenediaminepropylesalicylaldimine (SBA/EnSA), was developed for the recovery and preconcentration of trace amounts of uranium(VI) in water samples, prior to its determination spectrophotometrically using ArsenazoIII. For optimizing the parameters affecting the adsorption step (pH, adsorbent dose and adsorption time) and those influencing the desorption process (concentration and volume of eluent and desorption time), a statistical technique response surface methodology (RSM) was employed. The limit of detection and the linear dynamic range for the proposed method were 10 μg L, and 33.

Removal of uranium(VI) ions from aqueous solutions using Schiff base functionalized SBA-15 mesoporous silica materials.

Functionalized SBA-15 mesoporous silica particles, bearing N-propylsalicylaldimine and ethylenediaminepropylesalicylaldimine Schiff base ligands, abbreviated as SBA/SA and SBA/EnSA respectively, were prepared and characterized by FT-IR, elemental analysis, TGA, XRD, TEM and SEM techniques. The potentials of these adsorbents were examined by using them in solid phase extraction of U(VI) ions from water samples. It is shown that 20 mg of SBA/SA or SBA/EnSA can remove rapidly (∼15 min) and quantitatively uranium(VI) ions from 10 to 200 mL of water solutions (pH 4) containing 0.

Tetra-methyl-ammonium hydrogen terephthalate.

The asymmetric unit of the title salt, C(4)H(12)N(+)·C(8)H(5)O(4) (-), contains one half of a tetra-methyl-ammonium cation and one half of a hydrogen terephthalate monoanion. The N atom of the ammonium cation lies on a twofold rotation axis and the centre of mass of the terephthalate anion is on a centre of inversion. In the crystal, the centrosymmetric terephthalate ions are linked by a very short symmetric O-H⋯O hydrogen bond [O⋯O = 2.