Simultaneous determination of iron and titanium in silicate rocks by using diantipyrinylmethane with dual-wavelength spectrophotometry

The simultaneous determination of iron(III) and titanium(IV) with diantipyrinylmethane (DAPM) based on dual-wavelength spectrophotometry is described. The absorbances at 388 nm, 470, and 514.9 (A₃₈₈, A₄₇₀, A_514.9, respectively) are measured and a ratio k (= A₃₈₈/A_514.9) of 3.64 is introduced to allow simultaneous determinations of iron and titanium. The apparent molar absorptivities obtained by using the differences in absorbance, A₃₈₈—A_514.9, for titanium and A₄₇₀ × k — A₃₈₈ for iron, are 1.41 × 10⁴ and 1.13 × 10⁴ 1 mol^?1 cm^?1, respectively. The calibration graphs are linear up to 20 mg 1^?1 iron(III) oxide and 5 mg 1^?1 titanium(IV) oxide. The proposed method was applied successfully to the determination of iron and titanium in silicate rocks. The protonation equilibria of DAPM were also studied; K_a1 and K_a2 are estimated as 10^1.10 and 10^0.75, respectively.     

Extraction-Spectrophotometric or -Atomic Absorption Spectrophotometric Determination of Titanium Using Caffeic Acid and a Liquid Ion Exchanger

Abstract

A selective and sensitive method for the extraction followed by a spectrophotometric or atomic absorption spectrophotometric determination of titanium(IV) in trace amounts is described. The molar absorptivity of the caffeic acid-Aliquat 336 complex is 5.7 × 10⁴ l mol^?1 cm^?1 at 380 nm; the yellow coloured complex obeys Beer's law in the range 0.05–1.2 mg/l of titanium in the final extract. The method is applied to the preconcentration, separation and determination of titanium(IV) in steel, industrial effluents and environmental samples.     

Spectrophotometric Determination of Trace Amounts of Titanium in Geochemical and Metallurgical Samples

Abstract

The reaction between cyclohexan-1,2-dione bissalicyloylhydrazone and titanium(IV) has been studied spectrophotometrically. An orange complex (λ = 470 nm, ? = 1.49 × 10⁴ 1.mol^?1.cm^?1) is quickly formed at pH 1–2.5 in a 3+2 V/V ethanol/water medium. Interferences (more than 65 species) have been investigated. In presence of some masking agents most of metal ions do not interfere. The orange complex has been satisfactorily used for the determination of titanium in amphibolites, granites, suspended matter, Portland cement, bauxite, cast iron and duraluminium alloy. The results are compared with those obtained using AAS and ICP methods.     

New Spectrophotometric Method for the Determination of Titanium in Soil and Standard Geochemical Samples

Abstract

In the present communication a simple and rapid spectrophotometric method for the determination of titanium is described. The method is based on the reaction of Ti(IV) with a newly synthesized reagent, 6-(4-nitrophenylazo)-3,4,5-trihydroxy benzoic acid (NATHB), in ethanol medium at pH 3.2 to 4.2. The complex exhibits an absorption maximum at 495 nm and Beer's law is valid over the range of 0.04 – 1.00 μg.ml^?1 Ti. The molar absorptivity is 3.48 × 10⁴ dm³.mole^?1. cm^?1. Most of the foreign metal ions and anions do not produce any colorations with NATHB at selected conditions. Based on these results, a simple and direct spectrophotometric method with high selectivity and sensitivity was proposed. The method has been successfully applied for the determination of titanium in 5 soil and 3 standard geochemical samples.     

Catalytic Spectrophotometric Determination of Titanium(IV) Using Methylene Blue‐Ascorbic Acid Redox Reaction

A highly selective and sensitive catalytic method for the determination of trace amounts of titanium(IV) was developed. The method is based on the catalytic effect of titanium(IV) on the methylene blue‐ascorbic acid redox reaction. The reaction was followed spectrophotometrically by measuring the change in absorbance of methylene blue at 665 nm, 5 minutes after the initiation of the reaction. In this study experimental parameters were optimized and the effect of the presence of various cations and some anions on the determination of titanium(IV) was examined. The calibration graph was linear in the range of 3‐25 ng mL^?1 of titanium(IV). The relative standard deviation for the determination of 10 and 20 ng mL^?1 of titanium(IV) were 2.64% and 1.51%, respectively (n = 8). The detection limit calculated from three times of standard deviation of blank 3S_b was 0.6 ng mL^?1. The method was successfully applied to the determination of titanium(IV) in tap water and ore samples.     

Study of iron and titanium complexes with propylenediaminetetraacetic acid by differential pulse polarography : Determination of iron and titanium in Portland cements

Differential pulse polarography is used to study the iron(III) and titanium(IV) complexes with propylenediaminetetraacetic acid (PDTA). The complexes produce reduction peaks at –0.09 V and –0.32 V (vs. Ag/AgCl/3 M KCl), respectively, at pH 4.5. This is used for a simultaneous, precise determination of iron and titanium. The detection limits in aqueous solutions were 5.0 × 10^?7 M for iron and 3.0 × 10^?7 M for titanium and linear calibrations were obtained in the range 4.0 × 10^?4–6.0 × 10^?4 M in both cases. Correct results were obtained for iron trioxide (ca. 2%) and titanium dioxide (ca. 0.3%) in Portland cements, with relative standard deviations of about 3% and 6%, respectively.     

Novel Method for Selective Spectrophotometric Determination of Titanium(IV) with Water Extract of Slippery Elm Leaf as a New Reagent

Abstract

A novel spectrophotometric method for the determination of titanium(IV) by using a new reagent, water extract of slippery elm leaf is developed. In 0.05 M hydrochloric acid, titanium(IV) reacts with this reagent to form a yellow product. The formed product shows maximum absorbance at 415 nm with a molar absorptivity value of 0.68×10⁴ l mol^–1 cm^–1 and the method was linear in the 0.2–6 µg ml^?1 concentration range. The detection limit value was found to be 0.0131 µg ml^?1. The proposed method was simple, low cost, selective, and sensitive. It was applied to the analytic samples with satisfactory results.     

Reversed phase HPLC determination of titanium(IV) and iron(III) with sodium 1,2-dihydroxybenzene-3,5-disulfonic acid

A highly sensitive method has been developed for the determination of titanium(IV) and iron(III) by ion-pair reversed phase liquid chromatography using sodium 1,2-dihydroxybenzene-3,5-disulfonic acid (Tiron) as a precolumn chelating reagent. The metal - Tiron chelates were separated on a C₁₈ (ODS) column; the mobile phase was a 2:8 (v/v) mixture of acetonitrile and acetate buffer (0.04 mol/L, pH 6.2) containing 2.0 × 10^?3 mol/L Tiron, 0.04 mol/L tetrabutylammonium bromide, and 0.1 mol/L potassium nitrate. The detection limits for titanium(IV) and iron(III) are 0.5 and 2.0 μg/L, respectively. The method has been applied to the simultaneous determination of titanium(IV) and iron(III) in river water samples and has furnished highly precise results.     

Solvent extraction and spectrophotometric determination of titanium(IV) with 3-phenyl-3-methyl-2-mercaptopropenoic acid

The distribution equilibria of 3-phenyl-3-methyl-2-mercaptopropenoic acid (PhMMP) and the titanium(IV)-PhMMP complex have been studied. An extraction-photometric method for the determination of microamounts of titanium has been developed. We have investigated the influence of pH, the reagent, and the presence of electrolytes and masking agents in the aqueous phase on the equilibrium. From the slope analysis of the distribution curves the composition of the extracted species has been found to be Ti(OH)₂(HR)₂. The complex is extracted quantitatively. Beer's Law is followed over the range 0.09–3.74 μg ml^?1 of titanium(IV), the molar absorptivity is 1.65 × 10⁴ liters mol^?1 cm^?1, and the Sandell sensitivity is 2.8 ng cm^?2 at 439 nm. This method has been applied to the determination of titanium in a bauxite.     

Indirect Spectrophotometric Determination of Vanadium(IV) by Flow Injection Analysis Based on the Redox Reaction with Copper(II) in the Presence of Neocuproine

Abstract

An indirect photometric method with a continuous-flow analysis is presented for the determination of trace amounts of vanadium(IV). It is based on the redox reaction of copper(II) with vanadium(1V) in the presence of neocuproine. In the presence of neocuproine, copper(I1) is reduced easily by vanadium(I V) to a copper(1)-neocuproine complex, which shows a n absorption maximum at 454 nm. By measuring t h e absorbance of the complex at this wavelength, vanadium(1V) in t h e range 2×10^?6 - 8 × mol dm^?5 mol dm^?3 can be determined at a rate of 120 samples h^?1. The fractional determination of vanadium(1V) and iron(I1) is also studied.     

Cathodic Stripping Voltammetric Determination of Tellurium(IV) with in situ Plated Bismuth-Film Electrode

Abstract

A very sensitive and reliable method is proposed for the determination of tellurium(IV) [Te(IV)] by Osteryoung square-wave cathodic stripping voltammetry. This method is based on the reduction of Te(IV) with bismuth(III) onto an edge-plane pyrolytic graphite electrode, followed by a cathodic potential scan. The reduced Te gave a well-defined catalytic hydrogen wave at ?1200 mV vs. Ag/AgCl. The peak height of the catalytic wave was directly proportional to the initial Te(IV) concentration in the concentration ranges of 0.01–0.10 and 0.1–1.0 µg L^?1 with 30 s deposition time. A 3σ detection limit of 1.0 ng L^?1 Te(IV) was obtained with the same deposition time. The relative standard deviation was 3% on replicate runs (n = 5) for the determination of 0.1 µg L^?1 Te(IV). Analytical results of natural water samples demonstrate that the proposed method is applicable to the determination of traces of Te(IV).     

Spectrophotometric Determination of Copper(II) as the Azide Complexes,in the Presence of Iron(III) Cations

Abstract

A method for the spectrophotometrio determination of copper(II), in the presence of iron(III) cations (excess), was stablished. The masking of iron is made with sodium fluoride salt in 50 % (v/v) water/acetone medium. In the recommended conditions, absorbances for cupric complexes are measured at 435 nm where molar absorptivity is 6.00 × 10³ 1 mol^?1 cm^?1.

The stable ayetern obeys Beer's law and is suitable for the copper determination in concentration range from 2.0 to 9.0 mg 1^?l. The iron(III) ion interference (until ca. 600 mg 1^?l) can be completely suppressed. The influence of diverse ions and several others factore were studied.

The results show that copper(II) can be accurately determined by azide apectrophotometric method, if the samples were suitablely treated by the recommended procedure.     

Spectrophotometric Determination of Cobalt in Vitamin Preparations,Steel and Iron Using 2-Hydroxy- 1-Naphthaldehyde Guanylhydrazone

Abstract

A new spectrophotometric determination of cobalt with 2-hydroxy-1-naphthaldehyde guanylhydrazone in acid medium is described. The method is developed on the basis of a yellow cobalt (III) complex (molar absorptivity 1.32×10^?4 L.mol^?1.cm^?1 at 416 nm, stoichiometry 2:1). The method was applied to the determination of cobalt in vitamin preparations, steel and high-purity iron.     

Analytical applications of mixed-ligand complexes: II. Determination of hydrogen peroxide in the presence of perioxide derivatives

The mixed ligand complex TiXOH₂O₂ was found suitable for the determination of small amounts of hydrogen peroxide in the presence of peroxy acids of sulfur. The pH optimum for the determination depends on the concentrations of the reagents [titanium (IV) and xylenol orange]: for 2 × 10^?4M titanium (IV) and XO the optimum pH is 1.25. ?⁵²⁰ = 13,200 M^?1 cm^?1. The method is suitable for determination of 4–40 μM H₂O₂. Mention is made of the possible causes of the contradictions to be found in the literature concerning the ternary complex.     

Ti(IV) ion-imprinted polymer as a new selective sorbent for extraction and pre-concentration of trace amounts of titanium ions in different samples

ABSTRACT

In this paper, a novel, simple, selective and effective solid phase extraction method based on ion-imprinted polymer (IIP) technology and flame atomic absorption spectrometry (FAAS) for separation and pre-concentration of trace amounts of titanium (IV) ions was reportd?. It was obtained by precipitation polymerisation by using 2-(2,4-dihydroxyphenyl)-3,5,7-trihydroxychromen-4-one titanium (IV) complex abbrivated as Ti(IV)-(morin), as the template molecule. After polymerisation, leaching the polymer in HNO₃ (50% (v/v) solution caused formation cavities in the polymer. Characterisation studies of the ?Ti(IV)-imprinted polymer (Ti-IP) was performed by FT-IR, UV-Vis and scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDS) techniques and then, the effective factors on extraction were optimised. A sensitive response to Ti(IV) within a concentration range between 0.01 and 4.0 μg mL^?1 was achieved under the optimum conditions. A total of 10.0 ng mL^?1 and 80.0 mg g^?1 were obtained as limit of detection (LOD, 3Sb/m) and maximum adsorption capacity, respectively. The relative standard deviation (RSD) for eight replicates detections of 0.2 μg mL^?1 of Ti(IV)? was found to be 2.8%. By this method, pre-concentration factor (PF) of 100 was obtained. Successfully applying this method in the water and standard samples, reasonable results were obtained for the extraction and pre-concentration of the titanium ions.     

2-(2-Thiazolylazo)-pcresol (TAC) as a reagent for the spectrophotometric determination of titanium (IV)

The reaction between titanium(IV) and 2-(2-thiazolylazo)-p-cresol-(TAC) in aqueous methanol media at apparent pH 4.0–5.6 results in a intensely coloured complex that is stable for at least 2 h. The combining ratio is 1 1 cation TAC. Beer's law is obeyed up to 5.0 g/ml titanium(IV) at 580 nm. The apparent molar absorptivity at 580 nm is 9.82.10³ l.mole^–1.cm^–1 and the detection limit obtained was 5 ng/ml titanium (IV). A spectrophotometric method for the simultaneous determination of titanium and iron with TAC is proposed.     

Spectrophotometic Determination Of Tin In Steels With2-(5-Nltro-2-Pyridylazo)-5-[N-n-Propyl-N-(3-Sulfopropyl)Amino]phenol

ABSTRACT

A highly sensitive azo dye, 2-(5-nitro-2-pyridylazo)-5-[N-n-propyl-N-(3-sulfopropyl)amino]phenol (Nitro-PAPS), is used as a colorimetric reagent for the determination of tin(IV) content. Nitro-PAPS reacts with tin(IV) to form a water-soluble complex in 1.0 M acetic acid. Full color development is attained within 5 minutes, and maintains constant absorbance for at least 24 hours. The apparent molar absorptivity is 7.7 x 10⁴ dm³ mol^?1 cm^?1 at a maximum wavelength of 580 ran. Beer's law is obeyed for tin(IV) in the range of 0-1.2 μg ml^?1. The proposed method is successfully applied to the determination of trace amounts of tin in steels.     

Spectrophotometric extractive determination of Ti in mineral samples and aluminium alloys as a mixed-ligand Ti(IV)-salicylhydroxamic acid-thiocyanate complex

A sensitive method for the determination of titanium, based on the formation of a mixed-ligand Ti (IV)-salicylhydroxamic acid-thiocyanate complex and extraction of this into a liquid ion-exchanger phase has been developed. The extract has maximum absorbance at 400–460 nm and the apparent molar absorptivity is 1.8 × 10⁴l · mole^–1 · cm^–1 at 420 nm. The system obeys Beer's law at 420 nm in the range 0.16–3.20 mg/1 Ti, the detection limit being 0.1 mg/1. The method is found suitable for determination of titanium in aluminium alloys and silicate rocks.     

Extraction and Spectrophotometric Determination of Zirconium(IV)

Abstract

A sensitive and selective method for the extraction and spectrophotometric determination of Zr(IV) with N-p-chlorophenyl-3,4-,5-trimethoxycinnamohydroxamic acid (PTCHA) has been developed. The binary complex of Zr(IV)-PTCHA is extracted from 2–6 M HCl into chloroform, having a maximum absorbance at 385 nm; molar absorptivity 2.1 × 10⁴ 1 mol^?1 cm^?1. A ternary complex with xylenol orange (Zr-PTCHA-XO) have been studied in chloroform-ethanol media, which absorbs at 540 nm; molar absorptivity 4.3 × 10⁴ 1 mol^?1 cm^?1. The present method is applied for the analysis of zirconium in standard samples.     

Spectrophotometric Determination of Iron In Wines,Vegetables, Pharmaceutical Compounds and Minerals With Mandelohydroxamic Acid (Mha)

Abstract

A new reagent, mandelohydroxamic acid (MHA), which has an easy synthesis and an high water solubility (64.48 gL^?1) is proposed for a simple, rapid, selective and sensitive method for the spectrophotometric determination of iron based upon the formation of the MHA-Fe(III) complex and its extraction into n-butanol under optimum operating conditions. A yellow color is formed when the complex is extracted from acidic aqueous medium (Vw/Vo[dbnd]5) in the organic solvent (apparent molar absortivity 1.15 10⁴ L mol^?1 cm^?1 at a wavenlength of 430 nm). the relative error is 0.5% (2 ppm of iron) and the detection limit is 0.05 g mL^?1 of Fe(III). the method has been applied to the determination of iron in wines, vegetables, pharmaceutical compounds and minerals.