Organic acid solutions in the chromatography of inorganic ions VIII. Cation-exchange of Mn(II), Cd(II), Co(II), Ni(II), Zn(II), Cu(II), Fe(III), Sc(III), Y(III), Eu(III), Dy(III), Ho(III), Yb(III), Ti(IV) and Nb(V) in malate media

Summary The cation-exchange behaviour of Mn(II), Cd(II), Co(II), Ni(II), Zn(II), Cu(II), Fe(III), Sc(III), Y(III), Eu(III), Dy(III), Ho(III), Yb(III), Ti(IV) and Nb(V) in malate media at various concentrations and pH, was studied with Dowex 50 WX8 resin (200–400 mesh) in the ammonium form. Separation of Fe(III)/Cu(II), Fe(III)/Cu(II)/Zn(II), Fe(III)/Co(II)/Mn(II), Cu(II)/Ni(II)/Mn(II), Fe(III)/Cu(II)/Co(II)/Mn(II), Fe(III)/Cu(II)/Ni(II)/Cd(II), Yb(III)/Eu(III), Sc(III)/Y(III),Sc(III)/Yb(III)/Dy(III) and Nb(V)/Yb(III)/Ho(III) has been achieved, among others.This work was supported by C.N.R. of Italy.     

Distribution coefficients for twelve elements in oxalic acid medium on a strong anion-exchange resin

The distribution coefficients were determined for twelve elements, namely As(III), Ce(III), Cr(III), Co(II), Cu(II), In(III), Lu(III), Mn(II), Hg(II), Mo(VI), Sc(III) and Zn(II), on a strong base anion exchanger in pure oxalic acid solutions. The K_D curves are given. A scheme was developed for the chromatographic separation of five elements, namely As(III), Mn(II), Co(II), Zn(II) and Cu(II). Ce(III) can be separated from Lu(III).     

Adsorption of metal ions on activated carbon from aqueous solutions at pH 1-13

Adsorption of microgram amounts of 20 metal species on activated carbon powder from aqueous solutions of pH 1-13 was investigated. The species examined were Cs(I), Y(III), Ce(III), Ti(IV), Zr(IV), Cr(III), Cr(VI), Mn(II), Fe(III), Co(II), Ni(II), Ru(III), Cu(II), Ag(I), Zn(II), Cd(II), Al(III), Pb(II), Sb(III) and Bi(III).     

Separation and determination of trace amounts of beryllium(II), aluminium(III) and chromium(III) with chromotrope 2C chelates by RP-HPLC

A reversed-phase high-performance liquid chromatographic separation and determination of beryllium(II), aluminium(III) and chromium(III) with chromotrope 2C chelates on a C18-bonded stationary phase is reported. Methanol-water (45:55 v/v) containing 6 x 10(-3)M tetra-n-butylammonium bromide (TBAB) and 2 x 10(-2)M acetate buffer solution (pH 6.0) as mobile phase and with spectrophotometric detection at 530 nm was applied. The method has high sensitivity, the detection limits being 0.2 ppb for beryllium(I), 1 ppb for aluminium(III) and 2 ppb for chromium(III). Under the optimum conditions, most other metal ions did not interfere, e.g. up to 2 mg of Hg(II), Sn(II, IV), Pb(II), Bi(III), Ag(I), Zn(II), Cd(II), Cu(II), 1.5 mg of Fe(II), Co(II), Ni(II), 1.2 mg of Ca(II), Mg(II), Sr(II), Ba(II), 1 mg of Ga(III), In(III), 0.5 mg of Fe(III), 1 mg of Ga(III), In(III), 0.5 mg of Fe(III), 0.4 mg of Th(IV), Zr(IV). The method can be applied to the simultaneous determination of trace amounts of beryllium(II), aluminium(III) and chromium(III), in water, rice, flour and human hair samples.     

The stability constants of some metal chelates of triethylenetetraminehexaacetic acid (ttha)

Stability constants for Al(III), Cd(II), Co(II), Cu(II), Fe(III), Hg(II), La(III), Nd(III), Er(III), Mg(II). Mn(II), Ni(II), Pb(II), Th(IV) and Zn(II) complexes of triethylenetetraminehexaacetic acid (TTHA) have been evaluated from data obtained by pH and pM measurements. The pM method based on measurements with the mercury electrode and the redox system Fe(III)/Fe(II) proved to be very useful when binuclear complexes are formed.     

Capillary gas chromatographic analysis of pyrrolidinedithiocarbamate metal chelates

Pyrrolidinedithiocarbamate (PDTC) chelates of Zn(II), Cu(II), Ni(II), Co(III), Fe(III), Mn(II), Cr(III), and VO(II) were analysed by capillary GC on a DB-1701 column (30 m x 0.25 mm id) with flame ionisation detection (FID). Linear calibrations were attained within "1-30 microg/mL" for Ni(II), Fe(III), Mn(II), Cr(III), Cu(II), and VO(II), and within "2-50 microg/mL" for Co(III) and Zn(II). The limits of detection were in the "150-500 ng/mL" range, corresponding to 15-50 pg amounts reaching the FID system. The optimised method was applied to the determination of Cu(II) and Ni(II) in coins, and that of Zn(II), Cu(II), Ni(II), Fe(III), Mn(II), Cr(III), and VO(II) in pharmaceutical preparations with relative standard deviations within 1.1-5.2%. The results obtained are in good agreement with sewage water samples and the declared values for the pharmaceutical formulations, or with the results of AAS of metal contents in coins, pharmaceutical preparations, and sewage water samples.     

Ion flotation behaviour of thirty-one metal ions in mixed hydrochloric/nitric acid solutions

The ion flotation of 31 metal ions in hydrochloric/nitric acid solution with the cationic surfactant cetylpyridinium chloride was investigated. A 25-ml portion of 0.27-2.87 x 10(-4)M metal ion and 1.8-6.0 x 10(-4)M cetylpyridinium chloride solution in 0.17-3.4M acid mixture ([HCl]:[HNO(3)] = 2.4:1) was subjected to flotation in a cell, 22.5 cm high and 4.0 cm in diameter, for 5 min, with nitrogen bubbles. Ir(IV), Pt(IV), Ge(IV), Sn(IV), Bi(III), Au(III), Tl(III), Pd(II) and Sn(II) were floated from solution in 95-100% yield; Ru(III), Rh(III), Ir(III), Hg(II), Ag(I) and Tl(I) were partly floated, while Cr(VI), Ti(IV), Zr(IV), Ga(III), In(III), Fe(III), Sb(III), Al(III), Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II), CD(II) and Pb(II) were floated with less than 20% yield. The flotation behaviour of these metal ions in the mixed acid system was compared with that in hydrochloric acid. The flotation is more efficient in the mixed acid system.     

Metal complexes of isonicotinic acid hydrazide

Complexes of platinum(IV), ruthenium(III), rhodium(III), iridium(III), gold(III), dioxouranium(II), zinc(II), cadmium(II), mercury(II) and manganese(II) with isonicotinic acid hydrazide were prepared and characterized on the basis of analytical, conductometric, magnetic susceptibility and spectral data. Platinum(IV) ruthenium(III), rhodium(III), iridium(III), dioxouranium(II) and manganese(II) form six-coordinate complexes while gold(III), zinc(II), cadmium(II) and mercury(II) form four coordinate complexes.     

Thermal analysis of some metal benzohydroxamates

The preparation and thermal analysis of metal chelates of benzohydroxarnic acid (BHA) with Al(III), Cd(II), Co(II), Cu(II) (two compounds), Fe(III), La(III), Pb(II), Mn(II), Ni(II), U(VI) and Zn(II) is discussed. The Al(III), La(III), Pb(II) and Mn(II) chelates are new compounds. DTA and TGA curves of the chelates and of BHA are presented, and the heats of decomposition of the chelates are estimated.     

Extraction behavior of Tm(III), Dy(III) and Sm(III) lanthanide with N-benzoyl-N-phenylhydroxalamine

The extraction of Sm(III), Dy(III) and Tm(III) with N-benzoyl-N-phenylhydroxalamine (BPHA) in benzene at pH range (1–10) has been studied. Quantitative separation was found in borate media at pH 8. The slope analysis showed that the extracted complex was M(BPHA)₃, where M=Sm(III), Dy(III) and Tm(III). The effect of various masking agents indicated that EDTA, oxalate, fluoride, phosphate and citrate, interfered in this study. Decontamination study showed that Cu(II), Zn(II), Ni(II), Co(II), Cr(III), Sc(III) and Fe(III) had very poor separation factors, whereas Sn(II), Cd(II), In(III), Ru(II), Hg(II), Ag(I), Ta(V) and Hf(IV) had very large separation factor. The effect of different diluents showed that carbontetrachloride, chloroform, benzene, toluene, nitrobenzene dichloromethane, MIBK and cyclohexanone were equally good for extraction except TBP due to ion association.     

Polarographic analytical determination of Hg(II), Cu(II), Cd(II), As(III), Sb(III), Ti(IV) and U(VI) in the presence of Fe(III)

The analytical determination of Hg(II), Cu(II), Cd(II), As(III), Sb(III), Ti(IV) and U(VI) in the presence of Fe(III) and 1 M H₂SO₄ are investigated using the polarographic technique. The wave corresponding to the reduction of Fe(III) to Fe(II) was found to be completely suppressed by the addition of 1% pyrogallol. Thus, different mixtures of these elements, viz. Hg(II), Cu(II), Cd(II), As(III) and Fe(III)-mixture (A), Cu(II), Cd(II), Sb(III), As(III) and Fe(III)-mixture (B), and Cu(II), Cd(II), Ti(IV), U(VI) and Fe(III)-mixture (C), were quantitatively determined using 1% pyrogallol and 1 M H₂SO₄ as supporting electrolyte. The i₁/c results give excellent correlations in each case, as indicated from the results of leastsquares regression analysis.     

Separation and gravimetric determination of barium using sulfadimethoxin salicylaldimine

Sulfadimethoxin salicylaldimine (SUDMSA) has been found to be a wide spectrum precipitant of a number of metal ions. The chelates are granular, stable, and quantitatively formed. SUDMSA has been utilized for the gravimetric determination of barium in the presence of Ca(II), Sr(II), Fe(III), As(III), Sb(III), Cr(III), Ag(I), Cu(II), Ni(II), Co(II), Mn(II), Cd(II), Zn(II), Hg(II), Pd(II), Mg(II), Tl(I), ZrO(II), Sn(IV). The St. of the chelate was confirmed by elemental analysis and IR data.     

Organic acid solutions in the chromatography of inorganic ions-IV: cation-exchange of Mn(II), Cd(II), Co(II), Ni(II), Cu(II), Al(III) and Fe(III) in tartrate media

The cation-exchange behaviour of Mn(II), Cd(II), Co(II), Ni(II), Cu(II), Al(III) and Fe(III), in tartaric acid media was studied. Separations of Fe(III), Cu(II), Ni(II), Co(II), Cd(II) and Mn(II) on Dowex 50W X8 have been achieved.     

Selective Complexation of Hydrazone Based Ketimine with 3d, 4d,and 5d Metals: Synthesis,Characterization, and Biological Activity

Russian Journal of General Chemistry - The hydrazone derived ketimine of dehydroacetic acid and its metal {Cu(II), Ni(II), Zn(II), Fe(III), Cd(II), Pd(II), La(III), Nd(III), Ce(III)} complexes are...     

Using silica modified by Tiron for metal preconcentration and determination in natural waters by inductively coupled plasma atomic emission spectrometry

A new adsorbent is synthesized on the basis of silica consecutively modified by polyhexamethylene guanidine and 4,5-dihydroxy-1,3-benzenedisulfonic acid (Tiron) for the group preconcentration of Fe(III), Al(III), Cu(II), Pb(II), Zn(II), and Mn(II) followed by determination by inductively coupled plasma atomic emission spectrometry. The adsorbent in the batch mode quantitatively (recovery 98?99%) extracts Fe(III), Al(III) and Cu(II) ions at pH 4.0 and Fe(III), Al(III), Cu(II), Pb(II), Zn(II), and Mn(II) ions at pH 7.0; the time of attainment of an adsorption equilibrium does not exceed 10 min. Consecutive preconcentration at pH 4.0 and 7.0 in the batch and dynamic modes ensures the quantitative separation of Fe(III), Al(III), and Cu(II) from Pb(II), Zn(II), and Mn(II) and their separate determination. The quantitative desorption of metals was attained with 0.5?1.0 M HNO₃ (5 or 10 mL). In preconcentration from 200 mL of solution with 5 mL of a desorbing solution, the preconcentration coefficient was equal to 40. The developed procedure was used for the determination of metal ions in river waters of Krasnoyarsk Krai. The results obtained were verified by the added?found method.     

the extraction of some metallic bromides from aqueous solutions with methyl ethyl ketone and methyl iso-butyl ketone

The extraction of the following metals from aqueous solutions containing excess bromide with methyl ethyl ketone (MEK), and methyl isobutyl ketone MIBK has been investigated:—Cu(I), Cu(II), Zn(II), Ni(II), Co(II), Fe(II), Fe(III), Al(III), Mn(II), Sn(II) and Sn(IV). The use of MEK was found to be strictly limited by its solubility in acidic aqueous solutions. Determinations of the formulae of the extracted compounds were attempted in two cases but were found to be not wholly satisfactory and were discontinued. An interesting reaction between the cupric bromide complex and the solvents was noticed. Separations of Fe(IIl) from Mn(II), Fe(III) from Al(III), Fe(III) from Co(Il) and Fe(III) from Ni(II) could be achieved under suitable conditions.     

TRENDS IN THE OPTICAL ROTATORY DISPERSION SPECTRA OF R-(−)-1,2-PROPYLENEDIAMINETETRAACETATO COMPLEXES OF GROUPS IIA,IIB,IIIA,IIIB,IVB AND SOME HEAVY METALS

Abstract

A general periodic trend was observed in the optical rotatory dispersion spectra of the R-(?)-1,2-propylenediamine-tetraacetato (R(?)PDTA) complexes of Group IIA metals: magnesium(II), calcium(II), strontium(II), and barium(II); Group IIIB metals: scandium(III), yttrium(III), and lanthanum(III); Group IVB metals: titanium(IV), zirconium(IV), and thorium(IV); Group IIB metals: zinc(II), cadmium(II), and mercury(II); Group IIIA metals: aluminum(III), indium(III), and thallium(III); and the heavy metals: mercury(II), thallium(III), lead(II), and bismuth(III). The periodic trend was related to the ionic potential of the metals within each group, in that as the ionic potential increases within a group, the molecular rotations decrease from a positive to a negative value at any given wavelength outside of a region of anomalous optical rotatory dispersion. Comparing the heavy metal, mercury(II), lead(II), thallium(III), and bismuth(III), complexes of R(?)PDTA, outside of the region of anomalous rotatory dispersion, the metal with the same charge but smaller ionic potential has the greater positive molecular rotation at any given wavelength.     

Preparation, characterization and metal sorption studies of a Chrome-Azurol-S-loaded anion-exchange resin

Chrome Azurol S (CS) was mobilized on an strongly basic anion-exchange resin (Dowex 2 x 4, in Cl(-) form) by batch equilibration. The modified resin was stable in acetate buffer solution and in 0.1 M HCl and H(2)SO(4), but it was readily degraded with 2-6 M HCl and HNO(3). Retention of Ba(II), Sr(II), Ca(II), Mg(II), Al(III), Cr(III), Zn(II), Fe(III), Ti(IV), Mn(II), Co(II), Ni(II), Cu(II), Cd(II) and Pb(II) was studied using the batch equilibration method. The uptake and recovery yields were determined by using inductively-coupled plasma atomic emission spectroscopy (for Mg, Al, Cr, Ti, Fe, Mn, Ni, Zn, Cu, Cd and Pb) and atomic absorption spectrophotometry (for Ba, Sr, Ca and Co). The optimum pH value was established for performing a selective separation of Al(III) from the other metal ions. The sorption capacities of the CS-loaded resing for Al(III), Cr(III), Mg(II) (at pH 6), Fe(III) (at pH 5) and Ti(IV) (at pH 4) were 14, 2.9, 0.3, 3 and 3.9 mumoles g(-1) respectively. On this basis a method for separating Al(III) from other cations was established.     

Spectroscopic studies of transition metal complexes with a N-donor tetradentate(N4) 12-membered macrocylic ligand

Chromium(III), manganese(II), iron(III), cobalt(II), nickel(II), copper(II), ruthenium(III), iridium(III), palladium(II) and platinum(II) complexes were synthesized with a 12-membered 1,4,7,10-tetraazadodeca-5,6,11,12-tetraene macrocylic ligand (L) and characterized by elemental analysis, molar conductance, magnetic susceptibility, IR, electronic, EPR and M?ssbauer [Fe(III)] spectral studies. The molar conductance measurements of all the complexes in DMF solution correspond to non-electrolytic nature for M(L)Cl2 complexes [where M=Mn(II), Co(II), Ni(II), Cu(II)], 1:1 electrolytes for M'(L)Cl3 complexes [where M'=Cr(III), Fe(III), Ru(III) and Ir(III)] and 1:2 electrolytes for M'(L)Cl2 complexes [where M'=Pd(II) and Pt(II)]. Thus, the complexes may be formulated as [M(L)C1(2)], [M'(L)C1(2)]C1 and [M'(L)]C1(2), respectively [where L=ligand]. All complexes were of the high-spin type and found to have six-coordinate octahedral geometry except the Pd(II) and Pt(II) complexes which were four coordinate, square planar and diamagnetic.