Speciation of iron and manganese in dam water particles using electron spectroscopy for chemical analysis (ESCA)

Zaw, Myint; Chiswell, B.

doi:10.1016/0039-9140(94)00211-a

Cited by 18 publications

(11 citation statements)

References 19 publications

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“…The C 1s energy level is consistently centered around 284.6 eV with asymmetry in the higher binding energy side. C 1s spectra are fitted for four differently bound carbon species: (i) graphite or hydrocarbon (BE = 284.6 eV); (ii) alcohol, phenol, ether, or peroxide carbon (BE = 286.2 eV); (iii) carbonyl carbon (BE = 287.6 eV); and (iv) ester and carboxylic carbon (BE = 289.2 eV). The binding energy and full width at half-maximum (fwhm) values are given in Table .…”

Section: Resultsmentioning

confidence: 99%

Electrochemical and XPS Characterization of Glassy Carbon Electrode Surface Effects on the Preparation of a Monomeric Molybdate(VI)-Modified Electrode

Ilangovan

Pillai

1997

Langmuir

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Evaluation of electrochemical surface pretreatment methods on the preparation of monomeric molybdate(VI)-modified glassy carbon electrode (GCE) in H2SO4 is studied. The results show that the cathodically treated GCE is unusually highly activated toward Mo(VI) adsorption, but the anodized electrode does not respond, unlike the previous reports for the other adsorbed systems. The analyses of the voltammograms of Mo(VI) on a cathodized electrode show three pairs of reversible peaks with a surface excess on the order of ≅1 × 10-10 mol cm-2 for each of the peaks. The interaction parameters for the three processes are 1.14 × 109, 1.38 × 109, and −5.50 × 109 cm2 mol-1, respectively. Strong interaction between the Mo(VI) ion and cathodically reduced GCE surface groups is indicated by the formation of Mo(V) (detected by x-ray photoelectron spectroscopy (XPS) and electrochemical polarization measurements) during the course of Mo(VI) adsorption at open circuit conditions. The Mo(VI) adsorption via the mixed potential mechanism has been formulated involving Mo(VI) reduction to Mo(V) coupled with surface alcohol group oxidation to hydroperoxide. XPS analyses show that the cathodized surface contains higher amounts of >C−O− surface groups. The quantities of >C−O− surface groups correlate with the observed differences in the response of the pretreated GCE surfaces toward Mo(VI) adsorption.

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Section: Resultsmentioning

confidence: 99%

Electrochemical and XPS Characterization of Glassy Carbon Electrode Surface Effects on the Preparation of a Monomeric Molybdate(VI)-Modified Electrode

Ilangovan

Pillai

1997

Langmuir

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“…4 The speciation of iron and manganese compounds in water particles from a dam was studied by electron spectroscopy for chemical analysis (ESCA). 5 The chemical nature of Mn-containing particulates emitted from methylcyclopentadienylmanganese tricarbonyl-added gasoline engines was studied by Mn K-edge X-ray absorption fine structure spectroscopy (XAFS) and X-ray absorption near-edge structure spectroscopy (XANES). Three probable species contained in these particles were identified as Mn 2 O 3 , MnSO 4 and Mn 5 (PO 4 )[PO 3 (OH)] 2 4H 2 O.…”

Section: Introductionmentioning

confidence: 99%

Untitled

Thomassen

Ellingsen

Hetland

et al. 2001

J. Environ. Monitor.

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Workers in the Mn alloy producing industry are exposed to aerosols containing a variety of Mn compounds (MnO, MnO,, Mn2O3, Mn3O4, FeMn and SiMn). This paper reports a novel four-step chemical speciation/ fractionation procedure developed for characterisation of workroom aerosols collected in Mn alloy producing plants. The following components of the aerosol have been quantified: "water soluble" Mn dissolved in 0.01 M ammonium acetate: Mn0 and Mn2+ dissolved in 25% acetic acid; Mn3+ and Mn4+ dissolved in 0.5%) hydroxylamine hydrochloride in 25%) acetic acid; and "insoluble" Mn digested in aqua regia and hydrofluoric acid. Dissolution of pure Mn compounds with well-defined stoichiometries were essentially complete in the respective leaching steps with detectable amounts of < 1% in others. Recoveries of a mixed quality control sample were also acceptable in the range 92-97% for the different oxidation states. The levels measured in the inhalable and respirable fractions in three Mn alloy producing plants were approximately 300 and 35 microg m(-3) of total Mn, respectively. The most obvious feature of the speciation results is that none of the work areas is characterised by a single Mn contaminant. The predominant oxidation states in the inhalable aerosol fraction are Mn0 and Mn2+ independent of job functions/departments. The occurrence of insoluble Mn compounds in both the inhalable and respirable aerosol fractions is significantly higher during production of SiMn.

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“…4. Energy is given as kinetic energy (not as binding energy, generally [39]). It can be seen that the peak of the Mn2p electron binding energy is shifted in the case of the old and the treated Mn-bentonite, so it is very possible that in the case of the old Mn-bentonite there are mixed oxidation states (Mn(III) or Mn(IV)) present.…”

Section: Resultsmentioning

confidence: 99%