University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Website: @unf

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Classification: Industrial -> metallurgical

Citations 17

"A Robust Multisyringe System For Process Flow Analysis Part II. A Multi-commuted Injection System Applied To The Photometric Determination Of Free Acidity And Iron(III) In Metallurgical Solutions"
Analyst 2000 Volume 125, Issue 12 Pages 2364-2371
Fernando Albertús, Andreu Cladera and Victor Cerda

Abstract: A new software-controlled volume-based system for sample introduction in process flow injection analysis was developed. By using a multi-syringe burette coupled with one or two additional commutation valves, the multi-commuted injection of precise sample volumes was accomplished. Characteristics and performance of the injection system were studied by injecting an indicator in a buffered carrier. Three configurations were implemented in order to achieve two different tasks: the single injection of a sample in a two- or three-channels manifold, and the dual injection into different streams. The two channel flow system using the single injection was applied to the determination of free acidity in diluted samples containing high levels of iron(iii), by employing the single point titration methodology. The precipitation of ferric hydroxide was prevented using the ammonium and sodium salts of oxalate and acetate as buffer titrant. Methyl Red was employed as indicator. The procedure allows determination of acid concentration in solutions with a Fe(iii)/H+ molar ratio up to 0.2. Samples with higher Fe(iii)/H+ molar ratios were spiked with a known strong acid at dilution. The three-channel configuration was applied to the determination of ferric ions, using, as reagent, a merging mixture of sulfuric acid and potassium thiocyanate. The double injection system was implemented in series in a single (three-channel) manifold in such a way that a different injection volume and a changed reagent were used for each analyte. It was applied to the separated or sequential determination of free acidity and ferric ions. In this configuration, iron(iii) was determined using 0.5-0.7% (w/v) sodium salicylate solution as reagent. The systems can operate at up to 100, 84 and 78 injections per hour, respectively. Determinations on synthetic and process samples compared well with the reference values and procedures. Recoveries of 95-102% with a maximum RSD value of 5.4% were found for acidity. The respective values obtained for iron determinations were 96-105% and 4.3%.
Acidity Iron(III) Spectrophotometry Multicommutation Multisyringe Computer Titrations

"Flow Injection Systems With Inductively-coupled Argon Plasma Atomic Emission Spectrometry. 2. The Generalized Standard Addition Method"
Anal. Chim. Acta 1983 Volume 145, Issue 1 Pages 169-178
E. A. G. Zagatto, A. O. Jacintho, F. J. Krug and B. F. Reis

Abstract: In multicomponent analysis by inductively-coupled argon plasma emission spectrometry, the generalized standard addition method is useful in overcoming matrix and/or spectral interferences. As this method requires many standard additions, it becomes cumbersome when done manually if many elements are to be determined. By using a flow injection system, the standard addtion manipulations required can be significantly simplified and completed within a shorter period of time with much less sample material. A flow injection system with merging zones is used to demonstrate the method for analyzes of a Ni/Cu/Zn standard and of alloys. The reproducibility of measurements of the injected sample, with or without additions of standards is always better than 99%. The results obtained compare well with those obtained by the manual procedure and also with those obtained by atomic absorption spectrometry.
Copper Nickel Zinc Spectrophotometry Merging zones Standard additions calibration

"Potential Scanning Voltammetric Detection For Flow Injection Systems"
Anal. Chim. Acta 1983 Volume 153, Issue 1 Pages 325-330
Joseph Wang and Howard D. Dewald

Abstract: The possibility was investigated of using rapid-scan differential pulse voltammetry for detection in flow injection analysis. The measurements were made with use of a flow-cell (described and illustrated) equipped with either a carbon-paste or a vitreous-carbon disc electrode, a carbon-rod auxiliary electrode and a silver - AgCl reference electrode and with potential scanning at 2 V min-1. For paracetamol, calibration graphs were rectilinear in the range 0.1 to 0.5 mM (injection volume 0.2 ml) and the limit of detection was <1 µM. At the 0.5 mM level the coefficient of variation (n = 8) was ~4%. The proposed technique permits the selective determination of several electroactive species in multi-component mixtures; as examples, the simultaneous determinations of dopamine, paracetamol and chlorpromazine and of Cu, Pb and Cd are reported.
Acetaminophen Cadmium Caffeic acid Chlorpromazine Copper Dopamine Lead Electrode Electrode Electrode Voltammetry Flowcell

"Rapid Determination Of Lead, Bismuth, Antimony, And Silver In Steels By Flame Atomic Absorption Spectrometry Combined With Flow Injection Analysis"
Anal. Chim. Acta 1983 Volume 153, Issue 1 Pages 23-31
Nangen Zhou, Wolfgang Frech and Erik Lundberg

Abstract: The sample (1 g) is dissolved in concentrated HCl (7 ml) plus concentrated HNO3 (3.5 ml), the mixture is filtered through a glass-fiber filter (Whatman GF/A), and the residue is washed with 5% HCl, with which the filtrate is then diluted to 12.5 g. A 90 µL portion of the solution is injected into a carrier stream of water (5.6 mL min-1) and introduced into an air - acetylene flame (this technique combines the advantages of pulsed nebulization with those of continuous introduction of the solvent). Calibration graphs are rectilinear for up to 1 ppm of Ag and 10 ppm of Sb, Bi or Pb in the solution, although separate calibrations are necessary for Ag, Bi and Sb in low- and high-alloy steels. Results for a variety of standard steels were generally in good agreement with certified or published values. The limits of detection for Ag, Bi, Pb and Sb are 0.3, 2.5, 2.5 and 10 µg g-1, respectively. The rate of sampling is 120 h-1
Lead Bismuth Antimony Silver Spectrophotometry Pulse nebulization Reference material

"Online Electrolytic Dissolution Of Alloys In Flow Injection Analysis. 1. Principles And Application In The Determination Of Soluble Aluminum In Steels"
Anal. Chim. Acta 1986 Volume 190, Issue 1 Pages 177-184
H. Bergamin F&deg;, F. J. Krug and E. A. G. Zagatto, E. C. Arruda and C. A. Coutinho

Abstract: Polished steel samples were dissolved by electrolysis in a special cell (details given) and the solution was passed directly to a flow injection manifold as described by Krug et al. (Ibid., 1986, 179, 103). Dissolved Al was determined spectrophotometrically at 535 nm afte reduction with Eriochrome cyanine R (C. I. Mordant Blue 3) solution containing HCl, ascorbic acid and hexamine for pH adjustment. Beer's law was not obeyed and a second-derivative equation was used. The effects of electrolysis time, c.d. and electrolyte composition and flow rate were studied.
Aluminum, soluble Spectrophotometry Optimization

"Flow Injection Sample Introduction Methods For Atomic Absorption Spectrometry"
Analyst 1983 Volume 108, Issue 1283 Pages 153-158
Julian F. Tyson, John M. H. Appleton and Ahyar B. Idris

Abstract: The essential features of flow injection analysis are described and the use of flow injection methodology for sample introduction for flame atomic-absorption spectrometry is briefly reviewed. A flow injection analogue of the standard additions method has been devised and applied to the analysis of chromium in some BCS standard steels. The results showed good agreement with the certificate values. The use of a concentration gradient forming mixing chamber to provide a novel method of rapid, single-standard calibration is described and the results of preliminary experiments with magnesium show the method to be viable. The potential usefulness of both methods is critically evaluated.
Chromium Magnesium Spectrophotometry Gradient technique Standard additions calibration Review

"Determination Of Chromium In Steel By Flame Atomic Absorption Spectrometry Using A Flow Injection Standard Additions Method"
Analyst 1984 Volume 109, Issue 1 Pages 23-26
Julian F. Tyson and Ahyar B. Idris

Abstract: The determination of Cr in steel by AAS is briefly reviewed, and the basis of the flow injection standard-additions method (in which the sample solution is used as the carrier stream) is described. The effects of Fe concentration, fuel-to-oxidant ratio and dissolution procedure were investigated, and a method that requires no releasing agents and involves use of pure Cr standard solution is described. The selection of appropriate flow injection conditions by using the single well-stirred mixing chamber model for dispersion is discussed. The procedure permits a straightforward instrument-optimizing strategy to be used and can be readily adapted to the determination of more than one element in each sample.
Chromium Spectrophotometry Mixing chamber Review Standard additions calibration Well stirred mixing chamber Optimization

"Automated Flow Injection Spectrophotometric Determination Of Zinc Using Zincon: Applications To Analysis Of Waters, Alloys, And Insulin Formulations"
Analyst 1986 Volume 111, Issue 11 Pages 1311-1315
Michael A. Koupparis and Paraskevi I. Anagnostopoulou

Abstract: Water samples were filtered (0.45 µm membrane filter) followed by adjustment of the filtrate to pH 9 with 0.5 M borate buffer. Copper alloy samples were dissolved in concentrated HNO3 (10 ml), and the solution was diluted, neutralized with 5 M NaOH to phenolphthalein, and diluted with 0.05 M borate buffer. Insulin formulations were deproteinized with 1 M HCl (1 ml) and 0.61 M trichloroacetic acid (8 ml). After centrifugation, the supernatant solution (2 ml) was neutralized with 1 M NaOH (2 ml) and diluted to 10 mL with 0.05 M borate buffer. Aliquots (300 µL) of test solution containing <10 µg mL-1 of Zn were injected into a stream of mixed reagent (0.01 M KCN - 0.1 M ascorbic acid in borate buffer solution) at pH 9. After passing through a 150-cm mixing coil, the stream was mixed with a second reagent stream (10% cyclohexanone - aqueous 0.016% zincon in borate buffer solution) at pH 9. After reaction, the absorbance was measured at 620 nm with a detection limit of 0.05 µg mL-1 of Zn. Results were in agreement with reference values for the alloys by AAS.
Zinc Clinical analysis Spectrophotometry Method comparison Reference material

"Continuous Hydride-generation System For The Determination Of Trace Amounts Of Bismuth In Metallurgical Materials By Atomic Absorption Spectrometry Using An Online Stripping-type Generator/gas-liquid Separator"
J. Anal. At. Spectrom. 1997 Volume 12, Issue 6 Pages 637-642

Abstract: Sample-solution (1 M HCl medium) preparation procedures are presented for Sn alloys, steel, bronze and brass. A diagram of the flow injection manifold is presented; the sample solution and 1% NaBH4 solution (both 50 µL) are injected simultaneously into streams (both 1.9 ml/min) of water and 1 M HCl, respectively, which subsequently merge (cf. Bergamin et al., Anal. Chim. Acta, 1978, 101, 17) before passage through a 15 cm reaction coil a nd then through a stripping-type gas-liquid reactor-separator (made of acrylic; diagram presented). The generated BiH3 is carried in a stream of N2 to a quartz atomization furnace maintained at 900°C for absorbance measurement at 223.1 nm. The calibration graph is linear up to 100 ng/ml of Bi, and the detection limit is 320 pg/ml. The RSD (n = 20) at 100 ng/ml was 1.9%, and the results for standard reference materials and other alloy samples agreed with the certified values and results obtained by ETAAS, respectively.
Bismuth Sample preparation Spectrophotometry Phase separator Method comparison Reference material Volatile generation Volatile generation

"Determination Of Beryllium In Copper-beryllium Alloys By Flow Injection Spectrophotometry"
Fresenius J. Anal. Chem. 1981 Volume 309, Issue 5 Pages 363-364
Tadashi Mochizuki and Rokuro Kuroda

Abstract: A method is described for the flow-injection spectrophotometric determination of beryllium in Cu-Be-alloys using xylenol orange as reagent. Cu, Co and Fe are masked by means of thiosulphate and EDTA. Absorbance is measured at the maximum of 493 nm. With a flow rate of 4 ml/min 60 samples can be analyzed per hour with a relative standard deviation of about 1%.
Beryllium Spectrophotometry

"Rapid Continuous Determination Of Aluminum In Copper-base Alloys By Flow Injection Spectrophotometry"
Fresenius J. Anal. Chem. 1982 Volume 311, Issue 1 Pages 11-15
Tadashi Mochizuki and Rokuro Kuroda*

Abstract: A flow-injection spectrophotometric method has been developed for the rapid, continuous determination of aluminium in copper-base alloys. The system consists of the masking of copper, zinc, iron, etc. with a combined use of thiourea, ascorbic acid and EDTA and the measurement of light absorption of aluminium-Xylenol Orange complex at 506 nm. With appropriate standardization satisfactory results are obtained in spite of sluggish reaction of aluminium and Xylenol Orange. The system allows the analysis of solutions of copper-base alloys for aluminium to be conducted at a rate of 50 determinations per hour without any carryover. The results obtained for standard brasses and aluminium bronze (Al 1.43-10.2%) agreed well with the certified values. The precision (rsd) ranges are 0.2-0.3%.
Aluminum Spectrophotometry

"Rapid Determination Of Copper In Various Copper Base Alloys By Flow Injection Analysis"
Bunseki Kagaku 1980 Volume 29, Issue 10 Pages T73-T78

Abstract: A flow injection method is described for the spectrophotometric determination of copper in various types of copper-base alloys. The system utilizes either the light absorption of aquacopper(II) ion at 805 nm or the light absorption of colored complex of copper(II) with EDTA (730 nm). Simple dissolution of alloys in nitric acid in the presence of tartaric acid suffices for sample preparation. The procedures have been applied to standard samples of copper-base alloys including several types of brasses, beryllium copper, deoxidized copper, German silver and aluminum bronze. The results obtained agree very satisfactorily with the certified values for these alloys. The precision is better than 0.5 % for the aquacopper(II) ion method. The sampling rate is 1 7 samples per hour.
Copper Spectrophotometry Method comparison Reference material

"Determination Of Nickel In Nickel/iron Alloy Thin Films By Flow Injection Analysis"
Bunseki Kagaku 1987 Volume 36, Issue 4 Pages 233-237
Shirato, F.;Okajima, Y.;Kuroishi, T.;Takata, Y.

Abstract: A 0.25 mM 4-(2-pyridylazo)resorcinol solution in sodium borate buffer (pH 9.4) containing 0.22 mM Na2H2P2O7 (to mask Fe(III)) and solution of the sample were mixed in a carrier stream of water (1 mL min-1) and fed through a reaction coil (10 m x 0.5 mm) at 65°C and a back-pressure coil (5 m x 0.25 mm) at 25°C before the absorbance was measured at 520 nm in an 18 µL flowcell. The system enabled 30 analyzes per h with a coefficient of variation at 5 ppm of Ni of 0.09%. The method was applied to analysis of Permalloy thin films for which only 0.3 mg of sample was required.
Nickel Spectrophotometry Heated reaction Interferences

"Determination Of Iron In Nickel-iron Alloy Thin Films By Flow Injection Analysis"
Bunseki Kagaku 1987 Volume 36, Issue 9 Pages 515-519
Shirato, F.;Okajima, Y.;Kuroishi, T.;Takata, Y.

Abstract: In the flow injection system described, sample solution was injected into the carrier stream (H2O; 1 ml min-1) and allowed to react with reagent solution containing 0.5 mM 4,7-diphenyl-1,10-phenanthrolinedisulfonic acid(I) and 10 mM ascorbic acid in 0.3 M Na acetate buffer (pH 4.6) in a PTFE reaction coil (10 m x 0.5 mm) at 95°C. The absorbance of the Fe - I complex formed was measured at 535 nm in a 18 µL flow cell. The calibration graph was rectilinear from 0.5 to 1.5 ppm of Fe. The coefficient of variation (n = 14) for 1 ppm of Fe was 0.08%. The sampling rate was 20 h-1. The method was applied in the determination of Fe in nickel - iron alloy.
Iron Spectrophotometry Heated reaction

"Application Of FIA For Process Control Of Wet Non-ferrous-metal Refinement"
Bunseki Kagaku 1988 Volume 37, Issue 11 Pages T171-T175
Shimizu, H.;Murakami, M.

Abstract: Flow injection analysis with spectrophotometry or fluorimetry was applied to the determination of Cd, Cu(II), Fe(III), and Ga. Sample solution (25 µL) was injected into a carrier stream (0.65 to 0.7 mL min-1) to mix with the reagent solution (same flow rate) in the reaction coil, which was connected to a flow cell (18 µL) of a spectrophotometer. The carrier and reagent solution (respectively) were : (i) for Cu(II), acetate buffer (pH 5) and 10 µM-4-methyl-5-(sulfoaminoethyl)-2-(thiazol-2-ylazo)benzoic acid, (ii) for Fe(III), water and 2 M HCl and (iii) for Cd, sodium citrate (9 g) - potassium sodium tartrate (5 g) in 500 mL of 0.2 M NaCl, and 0.5 mM cation. Lumogallion and polyoxyethylene glycol dodecyl ether were used as fluorescent reagent and sensitizer, respectively, for the determination of Ga. The absorbance of the complexes of Cu(II), Fe(III) and Cd were measured at 585, 440 and 447 nm, respectively. The fluorescent adduct of Ga was determined at 560 nm (excitation at 485 nm). Interference from Mn(II), Co(II), Cr(III), Cr(VI) and Ni(II) was observed with the determination of Cd. Bivalent Fe, Ca, As(V) and SO42- interfered in the determination of Ga, but Zn, Cd, Fe(II), In and As(III) did not interfere. Calibration graphs were rectilinear for 0 to 5 µg mL-1 of Cu(II), 0 to 10 g L-1 of Fe(III), 0 to 1 mg L-1 of Cd and 0 to 3 µg mL-1 of Ga. The results agreed well with those obtained by AAS for Cu(II) or Cd, or by titration of Fe(III) with KMnO4.
Cadmium Copper Iron Gallium Calibration Interferences Process control Process control

"Robust Photometric Detector For Process Analysis"
Process Control Qual. 1992 Volume 2, Issue 3 Pages 249-255
G.D. Marshall, M.J.C. Taylor, D.E. Barnes and S.J.S. Williams

Abstract: The instrument described and illustrated incorporates a light-emitting diode, a transmitter to modulate the light output and a receiver to detect the modulated light. Two flow cells are used; one is formed by drilling a hole (1.1 mm diameter) through the body of the diode, and the other, of Z-shaped design, has a diameter of 0.5 mm. The apparatus has been used in a flow injection arrangement for the determination of V in samples from a solvent extraction V purification plant; ascorbic acid in 1% H2SO4 is used as carrier stream to reduce V(V) to V(IV), which is determined at 760 nm. The Z-shaped cell is subject to refractive index effects, which can be overcome by matrix matching or blank subtraction. Results obtained with the analyzer agreed with those of redox titration.
Vanadium Spectrophotometry Process monitoring Light emitting diode Flowcell Refractive index Method comparison

"Flow Injection Determination Of Phosphorus Deoxidized Copper"
Sumitomo Keikinzoku Giho 1983 Volume 24, Issue 3-4 Pages 108-113
Kato, Sakae; Toyoshima, Masayasu; Washida, Michio; Sagisaka, Kiyoji (SFS)

Abstract: A method was developed for the determination of P in P-deoxidized Cu by using a flow injection system. P in the sample was oxidized with HNO3 to give H3PO4, and the P was determined by spectrophotometry with ammonium molybdate. Dispersion effect for the peak max. concentration, effect of injection volume of sample plug, and operating temperature were investigated. The best operating conditions were obtained with a limited dispersion value of ~2 and a controlled temperature of 20-50°C. The coefficient of variation was <6% for 0.025% P. (SFS)
Copper Spectrophotometry Optimization Heated reaction