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: Environmental -> brine

Citations 21

"Preconcentration And Determination Of Calcium And Magnesium In Brine With Flow Injection Systems"
Anal. Chim. Acta 1988 Volume 214, Issue 1-2 Pages 439-445
Hiroko Wada, Heisuke Askura, Gogineni Venkata Rattaiah and Genkichi Nakagawa

Abstract: Calcium and Mg in brine were pre-concentrated on a column (5 cm x 2 mm) of Dowex A-1 resin (50 to 100 mesh), and eluted with 0.1 M HCl into a sample tube (20 cm x 0.5 mm) where the eluate was mixed with 1 M NH3 - NH4Cl buffer (pH 10.5) or with 1 M NH3 - NH4Cl buffer (pH 10.5) containing 1.04 mM Ba(II) and 1 mM EGTA (for determination of Mg). Either solution was then mixed with 50 µM-1-(2-hydroxy-4-diethylamino-1-phenylazo)-2-hydroxynaphthalene-3,6-disulfonic acid(I) solution before passing to a 300-cm reaction coil and thence to a flow cell for detection at 520 nm. The calibration graphs were rectilinear for up to 120 µg L-1 of Ca and 30 µg L-1 of Mg and detection limits were 5 and 0.6 µg l-1, respectively. Corresponding coefficient of variation were 1.8% (n = 7) and 1.4% (n = 9). The method was applied to determine Ca and Mg in commercial NaCl and KCl and results agreed with those from an AAS method. A simpler method that does not involve pre-concentration. is proposed for determination of Ca and Mg in brine from a diaphragm cell.
Calcium Magnesium Spectrophotometry Method comparison Optimization Preconcentration Tecator

"Flow Injection And Liquid Chromatographic Determination Of Aluminum Based On Its Fluorimetric Reaction With 8-hydroxyquinoline-5-sulfonic Acid In A Micellar Medium"
Anal. Chim. Acta 1989 Volume 225, Issue 2 Pages 339-350
José Ignacio Garciá Alonso, Angeles López Garciá, Alfredo Sanzmedel and Elisa Blanco Gonzales, Les Ebdon and Phil Jones

Abstract: Reaction of Al with 8-hydroxyquinoline-5-sulfonic acid (I) in cationic micelles of hexadecyltrimethylammonium bromide (II) formed a strongly fluorescent compound and allowed continuous determination of Al in flowing systems. At pH 6.3, with 0.2 mM I and 2 mM II, the detection limit for Al by flow injection analysis was 0.1 ng mL-1. The calibration graph was rectilinear for 100 ng mL-1, and the peak-height precision was 2% for 10 ng mL-1. Interference was greatly decreased compared with the batch method. The reaction was applied to the post-column detection of Al in fresh and high-salinity waters and dialysis fluid by ion chromatography, and for speciation of Al in serum after separation of proteins by ion-exchange LC.
Aluminum Fluorescence Interferences Buffer Speciation 8-hydroxyquinoline-5-sulfonic acid Dialysis Micelle

"Online Determination Of Sulfite In Brine By Flow Injection Analysis"
Anal. Chim. Acta 1990 Volume 238, Issue 1 Pages 171-175
P. MacLaurin, K. S. Parker, A. Townshend and P. J. Worsfold, N. W. Barnett, M. Crane

Abstract: The SO3- was reacted with 5,5'-dithiobis-(2-nitrobenzoic acid) at pH 11 to 12 and 70°C to 80°C in 18% KCl solution The reaction produced 2-nitro-5-mercaptobenzoic acid, and the absorbance of the solution was measured at 412 nm. The response was rectilinear up to 20 mg L-1 with coefficient of variation (n = 3) between 0.4 and 1.8%. The flow injection system and its operating costs are detailed.

"Discussion On"
Anal. Chim. Acta 1993 Volume 278, Issue 1 Pages 205-206
Wei Li and Jian Chen, Deng-Kui An*

Abstract: The cited paper (Zhu et al., Anal. Chim. Acta, 1992, 256, 97) describes an online determination of bromide ion in spent brine by combining fiber-optic techniques, continuous-flow sampling and a dual absorption cell system. Some errors have been found in the mathematical treatment of the dual cell system and the necessary corrections are presented.

"Automated Spectrophotometric Determination Of Titanium(IV) In Water And Brines By Flow Injection Based On Its Reaction With Hydrogen Peroxide"
Analyst 1990 Volume 115, Issue 3 Pages 315-318
M. Muñoz, J. Alonso, J. Bartrolí and M. Valiente

Abstract: A flow injection system is described (with diagram). Water (13 µL) in H2SO4 was injected into a 0.7 M H2SO4 carrier stream (2.2 mL min-1) and diluted in a coil (50 cm x 0.7 mm) with water (2.2 mL min-1). The stream was then mixed in a coil (1 m x 0.7 mm) with 3% (w/v) H2O2 in 0.7 M H2SO4 (2.2 mL min-1) and the absorbance was measured at 410 nm. Calibration graphs of Ti in the sample were rectilinear up to 1000 ppm at a sampling rate of 240 hmin1. Detection limit was 9 ppm, and the coefficient of variation was 0.6%. Interference from Fe, V and Mo can be avoided by selective precipitation during sample pre-treatment. A system is also described for the determination of low Ti concentration. in brine using 3.3 M Mg(NO3)2 - 1 M HCl as carrier; the calibration graph was rectilinear up to 30 ppm, coefficient of variation were 0.7% and the detection limit was 0.3 ppm.
Titanium(IV) Spectrophotometry Automation Dilution Calibration Detection limit Interferences

"Spectrophotometric Flow Injection Procedure For The Online Monitoring Of Sulfite In High-ionic-strength Brine"
Analyst 1991 Volume 116, Issue 7 Pages 701-705
Paul MacLaurin, Paul J. Worsfold, Alan Townshend, Neil W. Barnett and Michael Crane

Abstract: The effects of pH, temperature and KCl concentration. on the determination of SO32- in KCl brines by a previous method (cf. Anal. Chim. Acta., 1990, 238, 171) was investigated (details given). A modified online procedure is described, in which a stream containing brine (0.5 mL min-1), water (1.6 mL min-1) and disodium tetraborate - NaOH buffer solution (pH 9.9; 1.6 mL min-1) was mixed with water (1.6 mL min-1) containing a plug (20 µL) of 2.5 mM 2,2'-dinitro-5,5'-dithiodibenzoic acid and subsequent detection of the reaction stream at 500 nm. The calibration graph was rectilinear from 3 to 100 mg L-1 of SO32- with a coefficient of variation (n = 168) of 2.1%. Results were in good agreement with those obtained by an offline iodimetric procedure.
Sulfite Spectrophotometry Buffer pH Temperature

"Automation In Element Preconcentration With Chelating Ion Exchangers"
J. Anal. At. Spectrom. 1987 Volume 2, Issue 6 Pages 611-614
Günter Knapp, Kurt Müller, Martin Strunz and Wolfhard Wegscheider

Abstract: A microprocessor controlled pre-concentration system that permits the automated off-line pre-concentration of several samples at the same time is described. Trace elements pre-concentrated from sample volumes of up to several hundred millilitres can be eluted by 5 mL of 2 M nitric acid. It is therefore possible to achieve pre-concentration factors of up to 100. In contrast to FIA methods all ICP-AE spectrometers can be used for the measurements. Four different chelating ion-exchange materials, Chelex 100, oxine cellulose, CPPI resin and Hyphan cellulose, were compared. Trace elements were enriched from concentrated salt solutions and from NBS standard reference materials following decomposition in the High Pressure Asher. After elution the elements were measured by ICP-AES (Plasma II) and by graphite furnace AAS (HGA-500/Zeeman 5000). Under the conditions tested, Chelex 100, the oxine cellulose and the CPPI resin can be employed satisfactorily in the automated pre-concentration of a number of elements.
Cadmium Copper Lead Manganese Nickel Zinc Ion exchange Spectrophotometry Spectrophotometry Chelation Computer Preconcentration

"Determination Of Trace Metals In Concentrated Brines Using Inductively Coupled Plasma Mass Spectrometry Online Preconcentration And Matrix Elimination With Flow Injection"
J. Anal. At. Spectrom. 1993 Volume 8, Issue 7 Pages 979-981
Les Ebdon, Andrew Fisher, Howard Handley and Philip Jones

Abstract: Two chelation ion-exchange columns, an in-house (xylenol orange) one and a commercial (Metpac CC-1) one, were used for matrix elimination and online pre-concentration of the analytes (the alkaline-earth and first-row transition metals) before their determination in brines by ICP-MS with a VG Plasmaquad II instrument. Residual Na was determined by flame AAS. The method was used to determine the metals in seawater reference material NASS-3 (National Research Council of Canada). The response was linear in the range of interest (200 µg/l), and excellent agreement with the certified values was achieved. At the pH used, the in-house column retained all the alkaline-earth metals, but the transition metals were retained only slightly, so recovery was poor. The Metpac CC-1 column retained all the metals investigated and gave good precision.
Metals, trace Mass spectrometry Spectrophotometry Chelation Column Preconcentration Metpac Reference material

"Online Method For Inductively Coupled Plasma Mass-spectrometric Determination Of Rare-earth Elements In Highly Saline Brines"
J. Anal. At. Spectrom. 1996 Volume 11, Issue 9 Pages 811-814
Ludwik Halicz, Ittai Gavrieli and Ethel Dorfman

Abstract: The rare earths were pre-concentrated online, by a method based on their separation from the brine by adsorption on a microcolumn of silica-immobilized 8-hydroxyquinoline. A low pressure Perkin-Elmer FIAS 400 flow injection system was modified and was used with a Perkin-Elmer SCIEX Elan 6000 ICP-MS instrument. The rare earths were adsorbed on the column at pH 9 and eluted with a small amount of a mixture of 2 M HCl/0.8 M HNO3. The total time for a single analysis, including pre-concentration, was 9.5 min. Detection limits ranged from 0.06 ng/l for Tb and Ho to 0.6 ng/l for Ce and Nd.
Metals, rare earth Mass spectrometry 8-Hydroxyquinoline Silica FIAS-400 Preconcentration

"Application Of Adsorptive Stipping Voltammetry (AdSV) For The Analysis Of Trace Metals In Brine. II. Development And Evaluation Of A Flow Injection System"
Fresenius J. Anal. Chem. 1991 Volume 340, Issue 6 Pages 371-376
Axel Romanus, Helmut Müller and Dietmar Kirsch

Abstract: A flow system is described and illustrated for the determination of trace metals in brines by AdSV with use of the optimized conditions determined in Part I (see preceding abstract). The system comprised two low pulsation two-channel peristaltic pumps, a varible volume injection system, a programmable autosampler and a modified flow cell; automatic control was carried out by microcomputer. Limits of detection and coefficient of variation were similar to those obtained in Part I.
Metals, trace Voltammetry Automation Computer Multichannel

"Determination Of Calcium In Chlor-alkali Brine By Flow Injection Analysis"
Microchim. Acta 1985 Volume 87, Issue 5-6 Pages 393-400
H. Wada, Y. Deguchi and G. Nakagawa

Abstract: For calcium concentration of 1 mg L-1 in brine, the sample is diluted five times and injected into the flow injection system. For lower concentration, pre-concentration is achieved by passing the saturated brine, adjusted to pH 10 to 10.5 and at 60°C, through an acid- and alkali-washed column of Duolite ES-467 resin, from which Ca is eluted with 0.5 M HCl, the neutralized and diluted solution being injected for analysis. Samples enter a buffer stream (0.02 M Na2B4O7 of pH 8.0 containing 0.08 M NaCl) and react with a chromogenic solution containing 80 µM-ZnEGTA, 30 µM-3-{N-[4-(3,5-dibromo-2-pyridylazo)-3-hydroxyphenyl]-N-ethylamino}propanesulfonic acid and 0.02 M Na2B4O7 (pH 8.0). The absorbance of the resulting solution is measured at 564 nm. The calibration graph is rectilinear for 0.25 to 1.75 mg L-1 of calcium. Sample throughput is 40 h-1. Tervalent Fe, Cu(II) and Ni(II) can be masked with N-(dithiocarboxy)sarcosine, but Cd, Mn(II) and Zn interfere. The method has been applied to the determination of 20 to 80 µg L-1 of Ca in brine for the chlor-alkali process.
Calcium Spectrophotometry Interferences Resin Preconcentration

"Indirect Determination Of Iodine In Seawater And Brine By Atmospheric-pressure Helium Microwave Induced Plasma Atomic Emission-spectrometry Using Continuous-flow Cold Vapor Generation Of Mercury"
Microchem. J. 1990 Volume 41, Issue 2 Pages 148-155
Taketoshi Nakahara* and Tamotsu Wasa

Abstract: The method was based on the decrease of the Hg emission intensity in highly acidic solution due to the formation of Hg(II) - iodide complexes. The reductant, 0.02% SnCl2 in 0.1 M HCl and Hg(II) in 4 M HNO3 (10 ng mL-1) were added to the sample solution containing I- and the decrease in the Hg signal at 253.652 nm was measured. In the analysis of seawater and brine, IO3- was reduced to I- with 0.001% ascorbic acid. The response was rectilinear from 2 to 100 ng mL-1; limit of detection was 0.74 ng mL-1. The coefficient of variation (n = 100) for 50 ng mL-1 was 1.05%. Mean recoveries were >93%.
Iodine Spectrophotometry Detection limit Indirect Volatile generation Volatile generation

"Efficient Flow Injection Online Dilution System For Flame Atomic Absorption Spectrometry Based On Micro-zone Penetration"
Microchem. J. 1994 Volume 50, Issue 2 Pages 145-150
Xu S. K. and Fang Z. L.

Abstract: Combination of microsampling dilution with zone penetration produced an efficient automated dilution system for flame AAS capable of direct determination of Na, K and alkaline-earth metals in samples containing several g/l of the analytes. The highest dilution factor attained was 27 000 but values of 50 000 might be possible using updated software. Sampling frequency was 45/h and RSD were better than 2%. A drawback is that readouts have to be made manually on the recordings. The system was applied to the determination of Mg in brines used in bean curd production.
Sodium Potassium Metals, alkaline earth Magnesium Spectrophotometry Zone penetrating Dilution

"Separation Of Titanium And Iron In Brines By Solid Supported Liquid Membrane Using Tributyl Phosphate As Carrier"
Anal. Lett. 1991 Volume 24, Issue 10 Pages 1923-1934
Munoz, M.;Valiente, M.

Abstract: Use of a supported liquid membrane to separate mixtures of Ti(V) and Fe(III) in highly concentrated aqueous chloride is described. TBP was used as the extracting agent with solution containing Mg(NO3)2 and HCl as the stripping phase. The supporting liquid membrane was prepared by impregnating the microporous laminar support with the organic solution containing the extractant. The transport of Ti and Fe through the liquid membrane was monitored by online colorimetry using flow injection analysis. The effects of hydrodynamic conditions, membrane area, metal concentration, extractant concentration, pH and chloride concentration in the feed solution was investigated. A model was presented to describe the liquid membrane system.
Iron Titanium Sample preparation Extraction Liquid membrane pH Supported liquid membrane

"Gas Diffusion Flow Injection Analysis Applied To The Determination Of Sulfite And Sulfur Dioxide In Environmental Samples"
Chem. Anal. 1995 Volume 40, Issue 4 Pages 619-630
Frenzel, W.;Hillmann, B.

Abstract: To determine free sulfite, sample (300 µL) was injected into a carrier stream (1.2 ml/min) of water which merged with a stream (0.8 ml/min) of 0.2 M H2SO4 and passed through a reaction coil (60 cm x 0.7 mm i.d.). The SO2 produced was transferred to a stream (0.6 ml/min) of color reagent (50 mg 4,4'-dithiodipyridine, 10 mL ethanol and 1.02 g potassium hydrogen phthalate diluted to 250 mL with H2O) in a gas diffusion unit. It then passed through a reactor (45 cm x 0.7 mm i.d.) and the absorbance was measured at 324 nm. To determine gaseous SO2 collected in formaldehyde solution, samples (500 µL) were injected into a H2 carrier and treated with 0.45 M NaOH prior to acidification and release of SO2 (FIA manifold shown). The calibration graphs were linear for 0.25-10 and 0.5-20 mg/l free and bound sulfite, respectively, and the detection limits were 0.08 and 0.15 mg/l, respectively. The RSD were 1-3% and the sampling frequency was 20-30/h. Interferences were investigated. The methods were applied to the determination of sulfite in tap, surface and waste waters and brine, and to the determinations of SO2 in air (details given).
Sulfite Sulfur dioxide Spectrophotometry Gas diffusion Interferences

"Selective Determination Of Iodide And Iodate In Brine Waters By Atmospheric Pressure Helium Microwave-induced Plasma Atomic-emission Spectrometry With Continuous-flow Generation Of Volatile Iodine"
Chem. Express 1991 Volume 6, Issue 1 Pages 5-8
Nakahara, T.;Yamada, S.;Wasa, T.

Abstract: A method is described for the determination of iodide and iodate in brine by atmospheric pressure helium microwave-induced plasma AES. The method is based on the continuous evolution of volatile iodine by oxidation of iodide with sodium nitrate. Differentiation of iodide and iodate is achieved by pre-reduction of iodate to iodide with ascorbic acid. The detection limit is 2.3 ng mL-1 of iodine. Recoveries of added iodine were 94.2 to 103. 5%.
Iodate Iodide Spectrophotometry Selectivity

"Speciation And Determination Of Dissolved Iodide And Iodine In Environmental Aqueous Samples By Inductively Coupled Plasma Atomic-emission Spectrometry"
J. AOAC Int. 1996 Volume 79, Issue 3 Pages 751-756
Kim A. Anderson, Barbara Casey, Elmer Diaz, Peter Markowski, and Brent Wright

Abstract: Samples (5-10 ml) were filtered and diluted tenfold if the salt concentration was >1%. Iodide was determined after filtration by oxidation to I2 in situ with 5 M H2SO4/0.1 M NaNO2 in a simplified continuous-flow manifold (diagram given); a standard nebulizer separated I2 which was measured at 206.16 nm by ICP-AES with use of a Model Perkin-Elmer P-40 ICP-AES instrument with an AS-90 autosampler. I2 was determined without the use of the oxidation reagents. Samples containing both iodide and I2 were analyzed with the oxidizing reagent for the total iodine, without the oxidizing reagents for I2 and iodide was calculated by the difference of the two measurements. The method was applied to seawater, brine and fresh water. Recoveries were 86.5-118.6% with an average of 98.2%. The stability of I2 in environmental samples was briefly investigated.
Iodine Sample preparation Spectrophotometry Speciation

"Dispersion Of Matter In Turbulent Flow-through A Pipe"
Proc. Royal Soc. A 1954 Volume 223, Issue 1155 Pages 446-468
Geoffrey Taylor

Abstract: The dispersion of soluble matter introduced into a slow stream of solvent in a capillary tube can be described by means of a virtual coefficient of diffusion (Taylor 1953a) which represents the combined action of variation of velocity over the cross-section of the tube and molecluar diffusion in a radial direction. The analogous problem of dispersion in turbulent flow can be solved in the same way. In that case the virtual coefficient of diffusion K is found to be 10⋅1av* or K = 7.14aU√γ. Here a is the radius of the pipe, U is the mean flow velocity, g is the resistance coefficient and v* 'friction velocity'. Experiments are described in which brine was injected into a straight 3/8 in. pipe and the conductivity recorded at a point downstream. The theoretical prediction was verified with both smooth and very rough pipes. A small amount of curvature was found to increase the dispersion greatly. When a fluid is forced into a pipe already full of another fluid with which it can mix, the interface spreads through a length S as it passes down the pipe. When the interface has moved through a distance X, theory leads to the formula S^2 = 437aX(v*/U). Good agreement is found when this prediction is compared with experiments made in long pipe lines in America.
Theory Turbulent flow Laminar flow

"Immobilized Resins And Liquid Extractants For Potassium Extraction From Concentrated Brines"
React. Polym. 1991 Volume 14, Issue 1 Pages 81-84
S. Belfer and S. Binman, Y. Lati and S. Zolotov

Abstract: Potassium ions in concentrated chloride solution of alkali and alkaline-earth cations were extracted by solid - liquid or liquid - liquid extraction. For liquid - liquid extraction the organic phase consisted of a 10% solution of crown ether, Cyanex 301 [bis(2,4,4-trimethylpentyl)dithiophosphinic acid] or an equimolar mixture of the two, in toluene. The aqueous phase consisted of 0.2 M KCl, 2 M NaCl, 1.85 M MgCl2 and 0.5 M CaCl2. Equal volume (10 ml) of the organic and aqueous phases were equilibrated overnight and aliquots of both phases were withdrawn for anlaysis. The metal concentration. was measured by stripping the organic phase with 0.1N-HNO3. At pH 2 to 4 the main component in the organic phase is K; extraction was signifcantly improved by using the crown ether - Cyanex mixture. Solid - liquid extraction was carried out with use of a column of polystyrene resin impregnated with crown ether - Cyanex 301 (1:1). A mixture of 0.01 M NaCl and 0.01 M KCl (pH 10) was passed through the column (0.2 mL min-1) and elution was carried out with 0.1N-HNO3. Highly selective separation of K from Na was achieved in 0.01 M solution but the method is not suitable for concentrated brines due to the low capacity of the column.
Potassium Sample preparation Column Extraction Immobilized enzyme pH Resin Crown ether

"Performance Of An FIA - Flame AAS System Using An Electromagnetic Valve As Sampler"
Yankuang Ceshi 1989 Volume 8, Issue 4 Pages 300-303
Xu, P.;Hou, X.;Zhou, X.;Yan, D.

Abstract: A FIA - flame AAS apparatus with an electromagnetic valve as sampler is described. Factors influencing the dispersion and sampling frequency of the FIA as well as the precision of the whole system were investigated, e.g., the sampling volume, velocity of carrier flow and length of reaction circle. The system has been used in the determination of Li in brine by the standard-addition method and in the determination of Pd in geological samples after mercaptobenzothiazole - methylisobutyl ketone extraction.
Lithium Palladium Spectrophotometry Apparatus MIBK Precision Valve Standard additions calibration

"Automated Determination Of Sodium Chloride In Process Brines By Sodium-selective Electrode"
Zavod. Lab. 1984 Volume 50, Issue 5 Pages 3-6
Serikov, Y.A.;Bilinkis, D.L.;Komova, V.I.;Gurova, Z.I.;Belov, Y.A.

Abstract: The sample is clarified by passage through a cyclone and a settling chamber before entering a temp.-controlled chamber and a continuous-flow measuring cell. The cell contains a Na+-selective glass electrode and a silver - AgCl auxiliary electrode with a saturated KCl bridge. The potential of the electrode is measured with a high-resistance millivoltmeter. A NaCl reference solution of similar concentration. can be fed periodically into the measuring cell as a calibration check. The system can be used to determine and control the NaCl concentration. (5M) of process brines. In the 4 to 5 M range, the sensitivity is best and the equilibrium potential is reached in 5 to 15 s.
Sodium Electrode