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: Waste -> water -> industrial

Citations 28

"Detection Of Tannic Acid At Trace Level In Industrial Wastewaters Using A Highly Sensitive Chemiluminescence Method"
Water Res. 2003 Volume 37, Issue 1 Pages 233-237
Chenggen Xie and Hua Cui

Abstract: A novel flow injection procedure was developed for the determination of tannic acid in industrial wastewaters based on the enhancement by tannic acid of the chemiluminescence from luminol similar to K3Fe(CN)(6)-OH- system. The method has the merits of higher sensitivity, higher selectivity, wider linear range, simpler instrumentation. It is applicable for the determination of tannic acid in the range of 3.0 x 10^-10-1.0 x 10^-7 mol/L with a detection limit of 1.0 x 10^-10 mol/L. The relative standard deviation is 2.7% for the determination of 1.0 x 10^-8 mol/L tannic acid (n = 11). The method has been successfully used to determine tannic acid at trace level in industrial wastewaters from brewery and tannery. (C) 2002 Elsevier Science Ltd. All rights reserved.
Tannic acid Chemiluminescence Optimization Interferences Method comparison

"Solid-phase Sodium Bismuthate As An Oxidant In Flow Injection Analysis: Determination Of Manganese In Effluent Streams"
Anal. Chim. Acta 2000 Volume 413, Issue 1-2 Pages 57-61
K. Kargosha and M. Noroozifar

Abstract: An alternative procedure for the flow injection spectrophotometric determination of manganese(II) using a solid-phase reactor is presented. Solid sodium bismuthate (50% m/m suspended on silica gel beads) is packed in a polyethylene column, which is then incorporated in a single-line flow system so that reagent dissolution is affected as the sample passes through the column. Mn2+ in samples injected into a carrier stream were oxidized by solid sodium bismuthate to form MnO4- which were detected spectrophotometrically at 526 nm. The linear range of the system is 1-20 mg L-1 with a 3s detection limit of 0.38 mg L-1. The proposed system is suitable for determination of manganese(II) in effluent streams with a relative standard deviation <1.35%.
Manganese Spectrophotometry Solid phase reagent

"Pervaporation-flow Injection Determination Of Ammonia In The Presence Of Surfactants"
Anal. Chim. Acta 2000 Volume 416, Issue 2 Pages 177-184
Lijuan Wang, Terence J. Cardwell, Robert W. Cattrall, M. D. Luque de Castro and Spas D. Kolev

Abstract: A pervaporation flow injection method is described for the analysis of ammonia in complex matrices (e.g. in the presence of surfactants, solid particles). The donor solution is 1.0 mol L-1 NaOH while the acceptor solution contains mixed acid-base indicators cresol red and thymol blue. The color change resulting from the ammonia entering the acceptor stream in the pervaporation unit is monitored photometrically at 590 nm. The method is characterized by a linear calibration range between 0.2 and 20 mg L-1, sampling frequency of 11 h-1 and detection limit of 0.1 mg L-1. The presence of surfactants in high concentrations (1000 mg l-1) does not affect the analytical determination. The method was applied successfully to industrial effluents containing ammonia in the presence of surfactants, other organics and suspended solids.
Ammonia Spectrophotometry Pervaporation Interferences Surfactant Teflon membrane

"Continuous Monitoring Of Heavy Metals In Industrial Waste Waters"
Anal. Chim. Acta 1980 Volume 114, Issue 1 Pages 303-310
H. Cnobloch, W. Kellermann, D. K&uuml;hl, H. Nischik, K. Pantel and H. Poppa

Abstract: A relatively simple instrument is described for the continuous screening of groups of heavy metal ions in sewage and waters. The method is based on coulometric principles after concentration by preelectrolysis. The following metals can be detected: Ag, Hg, Pb, Cu, Co, Fe, Cd, Zn and Ni. An automatic laboratory model of the heavy metal ion detector has been tested successfully for eight months at the inlet of a municipal sewage plant and for nine months at the outlet of a neutralization plant of a galvanic shop.
Metals, heavy Silver Mercury Lead Copper Cobalt Iron Cadmium Zinc Nickel Coulometry Preconcentration Silica

"Flow Injection Determination Of Traces Of Formaldehyde By The Brilliant Green - Sulfite Reaction With Spectrophotometric Detection"
Anal. Chim. Acta 1991 Volume 252, Issue 1-2 Pages 167-171
A. Safavi* and A. A. Ensafi

Abstract: Solutions of SO32- (6 µg mL-1), phosphate buffer (pH 7.0), 50 µM-brilliant green (C. I. Basic Green 1) and the analyte (100 µL) were mixed in a flow injection system (diagram given) and the absorbance was measured at 615 nm at 25°C. The calibration graph was rectilinear from 4 to 300 ng of formaldehyde with a limit of detection of 20 ng mL-1. The coefficient of variation (n = 10) were 0.4% for 0.3 µg mL-1 and 0.2% for 1 µg mL-1. The method was applied to steam distillates from melamine - formaldehyde resin and industrial waste water. Other aldehydes only interfered at concentration. >20 µg mL-1.
Formaldehyde Spectrophotometry Buffer Interferences

"Sandwich Techniques In Flow Injection Analysis. 3. Simultaneous Determination Of Chromium(VI) In Two Concentration Ranges"
Anal. Chim. Acta 1992 Volume 261, Issue 1-2 Pages 219-223
J. Alonso-Chamarro*, J. Bartrol&iacute; and R. Barber

Abstract: A diagram is shown of the manifold, equipped with an eight-port switching valve, in which the sample is 'sandwiched' between two flows of 1,5-diphenylcarbazide (I) solution of different concentration. and absorbance measurements (at 540 nm) are made at the two sample - reagent interfaces; peak height is evaluated. Reagent 1 comprises 0.25 mM I and reagent 2 contains 1 mM I, each in 0.04 M H2SO4. By this means, two calibration ranges, from 0.02 to 1.0 and from 1 to 30 ppm (curvilinear) of Cr(VI), can be covered; the corresponding detection limits are 0.01 and 0.5 µg mL-1. Sample throughput is ~45 h-1 and the coefficient of variation is 1%. The method has been applied to the output from a pilot plant used to remove Cr(VI) from leather-factory waste water. A flow injection system based on the sandwich technique is proposed for the determination of Cr(VI). Two simultaneous working ranges of concentration. are achieved by appropriate selection of the reagent composition at the two reagent-sample interfaces. The optimized system allows the determination of Cr(VI) at levels up to 1 µg mL-1 with a detection limit of 0.01 µg mL-1 for one of the interfaces. For the other, determinations up to 30 µg mL-1 with a detection limit of 0.5 µg mL-1 are possible. The sample throughput achieved was about 45 h-1 with a relative standard deviation <1% in the middle of both ranges. The method was applied to determine Cr in water.
Chromium(VI) Spectrophotometry Sandwich technique Optimization Linear dynamic range

"Simultaneous Flow Injection Analysis For Two Components With Online Dialysis And Gas Diffusion In Series. Determination Of Chloride And Ammonia-nitrogen In Industrial Effluent Water"
Anal. Chim. Acta 1992 Volume 261, Issue 1-2 Pages 453-459
Jacobus F. van Staden

Abstract: A system is described and illustrated for the simultaneous determination of Cl- and ammonia-N. The sample plug (50 µL) from a single injection, in water as carrier, is routed first to the donor channel of a dialyser, where the Cl- diffuses into H2O; the diffusate is mixed with a reagent containing Hg(SCN)2 and Fe(NO3)3 in aqueous methanolic HNO3 before absorbance measurement at 480 nm. The sample plug is then treated with 0.1 M NaOH and passed to a diffusion unit, where the liberated NH3 passes into an indicator stream containing Tecator NH3 mixed indicator buffered at pH 5.0; the absorbance of the resulting solution is measured at 590 nm. Under optimized conditions, coefficient of variation were 0.8% for Cl- and 1.0% for NH3 in samples containing 127 to 2531 and 10 to 1000 mg L-1 of the respective analytes. The sampling rate was 100 h-1. Online dialysis and gas diffusion were combined for the simultaneous determination of >1 components in a single flow injection analysis system. A fast and reliable fully automated 2-component flow injection procedure is described in which a single sample (e.g., 50 µL of industrial effluent water) is injected into a carrier stream and sequentially dialyzed for the determination of Cl- and gas diffused for the determination of NH3. The results obtained for the Cl- and NH3 in industrial effluent water at a sampling rate of 100/h compared well with those obtained by standard methods.
Chloride Ammonia Spectrophotometry Method comparison Standard method Gas diffusion Dialysis Optimization Simultaneous analysis

"Chemical Oxygen Demand Determination In Well And River Waters By Flow Injection Analysis Using A Microwave Oven During The Oxidation Step"
Anal. Chim. Acta 1992 Volume 261, Issue 1-2 Pages 295-299
M. L. Balconi, M. Borgarello and R. Ferraroli*, F. Realini

Abstract: The sample (0.25 ml) is injected into water as carrier and, after mixing, the stream is treated with oxidizing solution prepared by adding dropwise, with vigorous stirring, 10 mL of aqueous 12% K2Cr2O7 to 300 mL of concentrated H2SO4 and diluting the cooled solution to 1 l with concentrated H2SO4. The resulting solution passes through a reaction coil (10 m) enclosed by a microwave oven operated at 180 W and then through a cooling coil and a de-bubbler before absorbance measurement at 445 nm. Under optimum conditions (described), the calibration graph is rectilinear for COD up to 100 mg l-1, and the detection limit is 1.5 mg l-1. The coefficient of variation was 2.1% (n = 20) at 40 mg l-1. Results obtained on well, river and canal water, sewage and food industry waste agreed with those by a standard method. A flow injection method based on the use of a microwave oven to maximize the rate of the oxidation step is described. The flow system consists of 2 lines (water as carrier and K dichromate-H2SO4 mixture as reagent), 3 coils, of which the intermediate one (wound around a special strong microwave absorber support) acts as reaction coil, a membrane degassing unit, and a spectrophotometric detector. Optimal parameters includes the oven capacity at 180 W, application range in 0-100 mg/L COD, relative standard deviation 2.12% at 40 mg/L COD, and detection limit 1.5 mg/L COD. Preliminary applications were made to well water, river water (with low COD levels), and wastewaters. The results obtained are in good agreement with those given by the manual reference method.
Chemical oxygen demand Spectrophotometry Microwave Method comparison Optimization Standard method

"Online Flow Injection Monitoring Of Ammonia In Industrial Liquid Effluents"
Anal. Chim. Acta 1995 Volume 314, Issue 1-2 Pages 33-43
Kevin N. Andrewa, Paul J. Worsfolda,* and Michael Comberb

Abstract: A portable, automated flow injection monitor was developed for the online determination of NH3 in industrial liquid effluent streams. The monitor was based on the diffusion of gaseous NH3 from an alkaline sample stream through a PTFE membrane into a bromothymol blue indicator stream and the photometric measurement of the resulting color change using a red LED (λmax = 635 nm). The effluent stream (1.3 ml/min) was mixed with a 0.01 M NaOH stream (1.3 ml/min) and a 20 µL volume of the mixture was injected into a water carrier stream (1.2 ml/min) and passed through the gas diffusion cell. The gas diffusion cell was equipped with a PTFE membrane (thickness 8-9 µm, 24 cm x 15 mm) and had a volume of 72 µL on either side of the membrane. I diffused through the membrane into a 0.1 g/l bromothymol blue stream (1.4 ml/min) and was carried to the detection cell. Calibration was carried out using two standard solution containing 2 and 80 mg/l NH3-N. The calibration graph was linear from 1-100 mg/l NH3-N and the detection limit was 0.6 mg/l. RSD (n = 10) were 3.4 and 0.7%, respectively, for the determination of 2 and 80 mg/l NH3-N. The performance of the monitor was evaluated at two industrial sites and the results were confirmed by an indophenol blue laboratory reference method.
Ammonia Spectrophotometry Gas diffusion Light emitting diode Method comparison Teflon membrane Portable

"Determination Of Sulfate In Natural Waters And Industrial Effluents By Sequential Injection Analysis"
Anal. Chim. Acta 1996 Volume 331, Issue 3 Pages 271-280
J. F. van Staden* and R. E. Taljaard

Abstract: A sequential injection analysis method with turbidimetric detection is described for the determination of sulfate. A flow rate of 5 ml/min was used to draw the following liquids into a holding column (2.8 m x 1.02 mm i.d.): 40% EDTA in NH4Cl/NH3 buffer for 5 s; water for 15 s; 1% BaCl2 in potassium hydrogen phthalate/HCl buffer of pH 2.5 containing 0.1% thymol and 0.06% gelatine for 3 s; sample for 9 s. The direction of the pump was reversed and the liquid zones were propelled through two reaction coils (1.3 m x1.02 mm i.d. and 1 m x 0.64 mm i.d.) to the detector were the turbidity was measured at 540 nm. A linear calibration graph was obtained for 10^-200 mg/l sulfate and the RSD (n = 10) were 1.1-2.81% over the same concentration range. The sampling frequency was 26/h. The method was applied to natural waters and industrial effluents and the results were confirmed by ion chromatography and a standard procedure using an AutoAnalyser.
Sulfate Turbidimetry Sequential injection

"Flow Injection Spectrophotometric Determination Of Total Phenols Using A Crude Extract Of Sweet Potato Root As Enzymic Source"
Anal. Chim. Acta 1998 Volume 366, Issue 1-3 Pages 111-118
Iolanda da Cruz Vieira and Orlando Fatibello-Filho*

Abstract: A flow injection spectrophotometric method is proposed for the determination of total phenols in industrial wastewaters. After selection of the extraction medium (e.g., buffer-to-tissue ratio, pH, buffer concentration, protective agents and/or stabilizers) and storage conditions, crude ext. of sweet potato root (Ipomoea batatas (L.) Lam.) was used as an enzymatic source of polyphenol oxidase (PPO; EC directly in the carrier. This enzyme catalyzes the oxidation of mono-, di-, and polyhydric phenols to o-quinones which can couple to each other producing melanin-like pigments with a strong absorption at 410 nm. For the optimum extraction conditions, the enzyme activity did not vary for at least five months when stored at 4°C and decreased only 4-5% during an 8 h working period at 25°C. The results obtained for the determination of total phenols in industrial wastewaters are in good agreement with results obtained using a conventional manual method (correlation coefficient, r=0.9954). Twenty-six results were obtained per h, and the relative standard deviation (RSD) was less than 2.7% (n=6) for all samples. The detection limit (three times the signal blank/slope) was 1.0 x 10^-5 mol/L and the recovery of catechol from three samples ranged from 96.4 to 102.7% of added amt.
Phenols, total Spectrophotometry Optimization Enzyme Method comparison

"Simultaneous Determination Of Trace Amounts Of Nickel, Copper And Mercury By Liquid Chromatography Coupled With Flow Injection Online Derivatization And Preconcentration"
Anal. Chim. Acta 1998 Volume 369, Issue 3 Pages 215-223
Akbar Ali, Hong Shen and Xuefeng Yin*

Abstract: Reversed phase liquid chromatography (LC) combined with flow injection (FI) online derivatization and pre-concentration resulted in a sensitive technique for analyzes of multi-metals at trace levels. A new home-designed micro-pre-concentration column containing RP-C18 material as solid sorbent, accommodated in a pressure-tight housing of stainless steel, combined with an LC six port valve was used to interface the flow injection online derivatization and pre-concentration system to the LC equipment. This pre-concentration column, which can be used for online derivatization and pre-concentration using peristaltic pump, proved to be strong enough to bear the high pressure of the LC eluent. Based on this FI-LC system, a method for the determination of Ni(II), Cu(II), and Hg(II) in water samples as their diethyldithiocarbamate (DDC) complexes was developed. A MeOH/H2O mixture (80:20 v/v) as LC eluent and intelligent UV detector programmed in time for absorption measurement at the max. absorption wavelength of the respectively. metal-DDC complexes were used. The detection limits were (signal : noise = 3) 0.16, 0.41 and 1.1 µg L-1 for Ni, Cu and Hg, respectively.; and the relative standard deviations were 3.6, 4.5 and 3.9% for Ni(II) (0.10 mg L-1), Cu(II) (0.10 mg L-1) and Hg(II) (0.40 mg L-1) (n = 6), respectively. The developed method was successfully applied to wastewater samples from an elec. power station and a machine tool factory and the results agreed with values determined by atomic absorption spectrometry.
Nickel Copper Mercury HPLC Spectrophotometry Method comparison Preconcentration Pre-column derivatization

"Speciative Determination Of Chromium(VI) And Chromium(III) Using Flow Injection Online Preconcentration And Flame Atomic-absorption Spectrometric Detection"
Anal. Chim. Acta 1998 Volume 369, Issue 1-2 Pages 69-77
T. Prasada Rao*, S. Karthikeyan, B. Vijayalekshmy and C. S. P. Iyer

Abstract: A rapid, sensitive and selective method for the speciative determination of Cr(VI) and Cr(III) in sea-water samples by flame atomic-absorption spectrometry, using online pre-concentration. on a micro-column packed with C18 bonded silica gel, was developed. This is based on the selective formation of diethyldithiocarbamate complexes of Cr(VI) in the 1-2 pH range and Cr(III) in the 4-9 pH range in the presence of Mn(II) (which enhances the Cr(III) signal 10-fold). The pre-concentrated species desorbed by MeOH directly from the column to the nebulizer-burner system using a flow rate of 4.0 mL/min. Five hundred-fold enrichment of Cr(VI) and Cr(III) was observed with a detection limit of 0.02 µg/l for a 5 min pre-concentration. time. The effect of probable concomitant species in seawater was determined and a satisfactory recovery of 95-105% could be obtained. Linear calibration curves were obtained for both the species, Cr(VI) and Cr(III), in the 0.2-200 µg/l concentration. range. Relative standard deviations were 3.5 and 5.1% for Cr(VI) and Cr(III), respectively, in the determination of 50 µg/l of each of these species. The developed procedure is suitable for the determination of Cr(VI) and Cr(III) species (Cr(total)) in various sea-water samples of western and eastern coasts of India. Further, the developed procedure was successfully applied for the determination of Cr(VI) and Cr(III) species in tannery and plating-bath effluents.
Chromium(III) Chromium(VI) Spectrophotometry Speciation Preconcentration C18 Silica Diethyldithiocarbamate Complexation

"Incorporation Of Electrodialyzers Into The Conduits Of FIA Systems: Enhancement Of The Mass Transfer Of Chloride Anions Through Passive Neutral Membranes"
Talanta 1998 Volume 45, Issue 3 Pages 485-492
J. F. van Staden* and C. J. Hattingh

Abstract: The viability of electrodialysis for the enhancement of mass transfer through passive neutral membranes in a flow injection system was studied. A Spectrapore and Technicon type C membrane were evaluated using chloride anions as analyte. Both membranes showed an increase in mass transfer and the proposed electrodialyzer/FIA system was applied for the determination of chloride in industrial wastewater with results that compared very well with a standard titration procedure.
Chloride Dialysis Membrane Method comparison

"Sequential Injection Determination Of Chromium(VI) By Transient Oxidation Of Brucine With Spectrophotometric Detection And Inline Dilution"
Analyst 1998 Volume 123, Issue 10 Pages 2085-2090
Paulo C. C. Oliveira and Jorge C. Masini

Abstract: A sequential injection method for the determination of Cr(VI) in wastewater from electroplating baths and steels is based on monitoring the absorbance at 525 nm due to an aminochrome intermediate compound resulting from oxidation of the alkaloid brucine. The intermediate brucichrome is unstable so that its anal. use is only possible in closed flowing systems where the precise and reproducible control of time and mixing is possible. The method gave a linear calibration curve from 0.2 to 2 mg Cr(VI)/L and a detection limit of 0.045 mg Cr(VI)/L. A sampling frequency of 120/h is possible. Industrial samples from electroplating baths and residual washing waters were analyzed; in this case a sequential injection in line dilution was performed, permitting real time determination of samples with Cr(VI) concentrations ≤100 mg/L with a sampling frequency of 80/h.
Chromium(VI) Spectrophotometry Sequential injection Indirect Redox

"Trace Enrichment And Determination Of Gold By Flow Injection Inductively Coupled Plasma Spectrometry. 1. Inductively Coupled Plasma Atomic-emission Spectrometry"
J. Anal. At. Spectrom. 1993 Volume 8, Issue 3 Pages 461-465
M. M. Gomez and C. W. McLeod

Abstract: The micro-column pre-concentration of Au in a flow injection system was studied with use of a PTFE column (4 cm x 1.5 mm) of Amberlyst A-26 (216 to 250 µm diameter) or of a PTFE column (7 cm x 1.5 mm) of mercaptoacetoxycellulose for which test recoveries of Au(III) from 0.25 mL of a 1 mg mL-1 solution were 90 to 98 and 95 to 100%, respectively. Samples (10 ml) of refinery effluent waters were fed for pre-concentration at 1 mL min-1 and for a 0.25 mL eluent volume factors of 40 for Amberlyst and 50 for mercaptoacetoxycellulose were achieved. Both provided rectilinear calibration graphs for up to 100 µg L-1 of Au. For Amberlyst the detection limit was 1.7 µg L-1 and the coefficient of variation at 50 µg L-1 was 3.5%; for mercaptoacetoxycellulose the corresponding values were 0.8 µg L-1 and 1.2%.
Gold Mass spectrometry Spectrophotometry Preconcentration Mercaptoacetoxycellulose fiber

"Simultaneous Flow Injection Analysis For Two Components With A Double Online Dialyser. Determination Of Calcium And Chloride In Industrial Effluent Water"
Fresenius J. Anal. Chem. 1993 Volume 346, Issue 6-9 Pages 723-727
Jacobus F. van Staden

Abstract: Samples (50 µL) were injected into an water carrier stream (3.9 ml/min) and were transported to a dialysis cell equipped with two Technicon type C membranes. Each of the membranes permitted the analytes to diffuse into separate water streams (both 3.9 ml/min). In the chloride stream the dialysed material was mixed with Hg(SCN)2-Fe(NO3)3 reagent (2.5 ml/min) and the absorbance was measured at 480 nm. The method was suitable for 0.1-2.5 g/l of chloride. In the Ca(II) stream the dialysed material was mixed with a cresolphthalein complexon reagent (3.9 ml/min) and then with 2-amino-2-methylpropan-1-ol solution (2 ml/min) to adjust the pH to 10^-11 and the absorbance was measured at 580 nm. The method was suitable for 0.1-1.5 g/l of calcium. When the method was applied to industrial waste water the results agreed well with those obtained by standard methods. In the ranges cited the RSD were 0.9% for chloride and 1% for Ca. The sampling rate was 90 per h.
Calcium Chloride Spectrophotometry Dual detection Membrane Dialysis Method comparison Standard method

"Simultaneous Flow Injection Determination Of Ammoniacal Nitrogen And Chloride In Industrial Effluent Water With A Combined Online Gas Diffusion/dialyser Unit"
Fresenius J. Anal. Chem. 1995 Volume 351, Issue 8 Pages 758-761
Jacobus F. van Staden, Cornelius J. Hattingh and Daniel Malan

Abstract: Industrial effluent was injected into a carrier stream (2.5 ml/min) of water, the stream was mixed with a stream (1.2 ml/min) of 0.1 M NaOH in a mixing coil (100 cm x 0.76 mm i.d.). The resulting stream passed into a gas diffusion/dialyser unit. The unit has two recipient channels; the top channel is separated from the donar channel with a PTFE membrane and contains ammoniacal indicator mixture (2.5 ml/min). The bottom channel is separated from the donar channel with a dialysis membrane and contains water (2.5 ml/min). The ammonical nitrogen stream passed through a coil (200 cm x 0.76 mm i.d.) and the absorbance was measured at 590 nm. The water dialysic stream was merged with a color stream (1.2 ml/min) containing mercury(II) thiocyanate in methanol, concentrated nitric acid and iron(III) nitrate in water. The resulting mixture passed through a coil (200 cm x 0.76 mm i.d.) and the absorbance of the chloride was measured at 480 nm. Calibration graphs were linear for 0.1 g/l ammonical nitrogen and 0-2.531 g/l chloride with RSD (n = 15) of 0.16-0.98% and 0.16-0.45%, respectively.
Ammonia, nitrogen Chloride Spectrophotometry Dialysis Gas diffusion Simultaneous analysis Teflon membrane

"Tandem Online Dialysis With A Double And Single Dialyser In Flow Injection Dialysis-simultaneous Determination Of Calcium And High Chloride In Industrial Effluents"
Fresenius J. Anal. Chem. 1995 Volume 351, Issue 2-3 Pages 181-185
Jacobus F. van Staden

Abstract: A previously described online double membrane dialyser (cf. Ibid., 1993, 346, 723) was coupled in series with a single dialyser in the tandem mode in a flow injection manifold for the cited analysis (diagram given). The double online dialyser separated the analytes from interferents by dialysing a single sample plug into two different recipient streams. The resulting Ca plug was channelled to the detector immediately; the chloride plug was dialysed, and the dialysate was channelled to the detector. Details of the chromogenic reagents used are given. Detection was performed at 480 and 580 nm for chloride and Ca, respectively. A sampling rate of 90 samples/h was achieved with RSD of 1.0% for free Ca and 0.8% for high concentrations of chloride, respectively. The method was used for the analysis of industrial effluents containing 5-60 g/l of chloride and 100-1500 mg/l of Ca. Results are discussed.
Calcium Chloride Spectrophotometry Dialysis Dual membrane Interferences Chromogenic reagent

"Determination Of Organic Compounds In Aqueous Waste Streams By Online Total Organic Carbon And Flow Injection Analysis"
Am. Chem. Soc. Symp. Ser. 1992 Volume 508, Issue 1 Pages 62-78
W. W. Henslee, S. Vien, and P. D. Swaim

Abstract: Pollution Prevention in Industrial Processes. The determination of soluble organics in wastewater streams is important for efficient operation of biological treatment facilities, compliance with regulatory permits, detection of process upsets, and material balances around manufacturing units. Grab and composite samples, followed by TOC (total organic carbon) measurements in the lab. are often too slow to provide time for an appropriate response. Accuracy, precision, sensitivity and stability data are given for a commercial available TOC analyzer. In some cases, the time for a TOC measurement is too long for adequate response to a spill or process upset. Two cases are discussed in which flow injection analysis was used instead of TOC. Both involve the detection of amines in waste streams.
Amines Total organic carbon Total organic carbon Method comparison

"Chemiluminescence Reaction In Chromium(VI) - Ferrocyanide - Luminol System"
Fenxi Huaxue 1992 Volume 20, Issue 1 Pages 61-63
Lu, J.R.;Zhang, X.R.;Zhang, Z.J.

Abstract: Tapwater, river water or industrially-polluted water is applied at 5 mL min-1 to a column (20 x 2 cm) of 732 strongly-acidic cation-exchange resin. Some of the eluate is mixed with 0.5 mL of 0.1% K4Fe(CN)6, 0.5 mL of 0.1 M HCl, 0.5 mL of 1% KAl(SO4)2, 0.5 mL of 10 mM EDTA and water to 50 mL and the solution is injected into a flow injection chemiluminescence analyzer. for reaction with 2.5 mM luminol in 0.4 M NaOH followed by chemiluminescence detection. The calibration graph was rectilinear from 0.1 ng mL-1 to 6 µg mL-1 of Cr; the detection limit was 20 pg mL-1. The coefficient of variation was 2%. Only VV interfered. Results are compared with those obtained by diphenyl carbazide method.
Chromium(VI) Ion exchange Chemiluminescence Interferences Method comparison

"Application Of Kelgraph To Electrochemical Detectors For Flow Injection Analysis And High Performance Liquid Chromatography"
Gov. Rep. Announce. Index 1983 Volume 83, Issue 2 Pages 4961-4961
Weisshaar, Duane E.

Abstract: The active area of Kel-F graphite composite (Kelgraf) electrodes determined from short time chronoamperometric data agree well with the weight percent of graphite in the composite and with the percent conducting carbon on the surface determined from x-ray photoelectron spectroscopy (XPS). The performance of Kelgraf as an electrode for electrochemical detection in flowing streams is discussed, including the determination of the optimum electrode composition and the linear dynamic range of the detector. The detector was applied to the determination of phenols in groundwater and coal gasification waste water. Detection limits ranged from 3-15 pg for a variety of phenols. No fouling of the electrode was evident. Evidence based on chronoamperometry, XPS, SEM, cyclic voltammetry and capacitance measurements point to the existence of a partial thin film of Kel-F over portions of the graphite sites. The implications of the presence of such a film are also discussed.
Phenols Electrode HPLC

"Application Of Amperometric Flow-through Gold Tubular Detector Determination Of Trace Sulfide Ion By Flow Injection Analysis"
Huanjing Huaxue 1984 Volume 3, Issue 5 Pages 75-79
Ma, Huichang; Yan, Huiyu

Abstract: The amperometric detector using a Au-tubular electrode is suitable for trace sulfide determination in surface water and pulp wastewater at pH > 5-6 and applied external voltage +300 mV. The linear response covers three orders of magnitude in the ppb ppm range, the relative standard deviation is ≤3%, and the detection frequency is 60/h. Interference by phenol and cyanide is insignificant at pH 5-6.
Sulfide Amperometry Electrode Interferences

"Multi-channel Wastewater Monitoring System For Phosphorus Based On Flow Injection Analysis"
J. Flow Injection Anal. 1992 Volume 9, Issue 1 Pages 47-57
Masaya Aoyagi,Yoshiaki Yasumasa* and Tatsuo Himeo*

Abstract: Trace PO43--P was determined in wastewater by flow injection absorption spectrometry at 650 nm using 25% EtOH solution of 0.015 M (NH4)2MoO4 and 2.18 x 10^-4 M malachite green. The calibration graph was linear, and the determination limit was 5 ng/mL. The method was applied to multi-channel wastewater monitoring system for treatment of wastewater from agricultural organophosphorus chemical plant. The PO43--P concentrations in wastewater treated by the activated-sludge process and Ca(OH)2 precipitation process, and those in final effluent were 10^-30, 5-10, and 0.7-1.5 ppm, respectively, during 40 days operation. Trouble shooting and maintenance record during 8 yr operation are described.
Phosphorus Spectrophotometry Multichannel

"Evaluation Of The Operational Parameters Affecting Dispersion In Sequential Injection Analysis"
South Afr. J. Chem. 1998 Volume 51, Issue 2 Pages 100-108
Van Staden, J.F. & Botha, A.

Abstract: Sequential injection analysis (SIA) is known for its use as an analysis technique, having the advantage of reduced sample and reagent consumption compared with flow injection analysis (FIA). An important aspect that needs critical attention in the optimization of this system is the dispersion, which could have a direct effect on the zone penetration that takes place within the SIA flow conduit. The dispersion in the SIA manifold is influenced by certain operational parameters, and studies were carried out to study the effect these parameters have on dispersion. Because of a lack of information on the effect operational parameters have on the dispersion that takes place within an SIA flow conduit, it was decided to study these parameters in depth to contribute to this knowledge. A study was made on the effect mixing chamber have on dispersion within the SIA manifold. The optimized dimensions of the parameters that were studied are: pump tubing internal diameter (internal diameter), 1.85 mm; pump speed, 18.0 rpm (peristaltic pump); sample and reagent zone volumes, 600.0 and 1200.0 µL; holding coil length, (3.50 m) and internal diameter (1.60 mm); reaction coil length (1.10 m) and internal diameter (1.02 mm); and a 1.0 mL mixing chamber in the holding coil position of the SIA manifold.
Sulfate Dispersion Sequential injection Dilution Mixing chamber Optimization

"Determination Of Microamounts Of Uranium By Flow Injection Analysis"
Youkuangye 1987 Volume 6, Issue 3 Pages 33-37
Xia Buyun Liu Shaorong

Abstract: A spectrophotometric determination of uranium is presented by means of self-made Flow Injection Analysis System controlled by a microcomputer. The method uses 2-(5-bromo-2-pyridylazo)-5-diethyl-aminophenol (Br-PADAP) as chromogenic reagent of uranium at the presence of cetypyridium bromide (CPB) which makes the determination possible in aqueous solution. The common ions in the solution do not interfere the determination of uranium. The range of the determination is 0.1-2.0 mg/L (uranium). The relative standard deviation is less than 2%. About 60 samples can be analyzed per hour. The method is suitable for the analysis of microamount of uranium in waste water of uranium mills.
Uranium Spectrophotometry Computer Interferences

"Automatic And Rapid Analysis Of Micro Lead In Industrial Waste Water"
Yejin Fenxi 1998 Volume 18, Issue 4 Pages 6-8
Xu, Hongliang; Liao, Qinxian; Xu, Jinhua

Abstract: A method for the determination of µPb in industrial waste water based on the flow injection-spectrophotometry by an automatic photometric analyzer was presented. A complex was formed by Pb and 5-Br-PADAP in the presence of OP in pH 9.0 NH4OH-NH4Cl buffer solution The determining wavelength was 570 nm, the Beer's law was obeyed at 0-4.0 µg mL-1, and the molar absorptivity was 6.9 x 104. The anal. process including zeroing, sample loading and injecting, data reading, standard calibration, measurement of absorbance and results printing can be completed in 90 s. The sampling frequency was 40 samples/h. Ethylenediamine-acetylacetone-triethanolamine- K4[Fe(SCN)6] were used as masking agents. The method was applied to determine Pb in waste water at Zhuzhou Smelter with the RSD 0.31-0.34%.
Lead Spectrophotometry Complexation

"Automated Determination Of Metal Ions In Industrial Waste Waters"
Zavod. Lab. 1991 Volume 57, Issue 8 Pages 9-12
Borovkov, G.A.;Shcherbin, O.V.

Abstract: For the determination of Cu and Zn by differential pulse voltammetry, a system comprising an AZhE-11 automatic flow-through analyzer. and a stationary-Hg-drop electrode was used. Measurements were carried out from -0.2 to -1.4 V vs. Ag - AgCl in 0.5 M NH3 - 0.5 M NH4Cl as supporting electrolyte. The scan rate was 10 mV s-1, the pulse amplitude was 40 to 50 mV, and the respective peak potentials for Cu(NH3)42+ and Zn(NH3)42+ reduction were -0.43 and -1.25 V. Calibration graphs were rectilinear up to 500 mg L-1 of Cu and Zn. Trace Cd2+, Ni2+, Co2+, As(V) and Cl- did not interfere. Interfering O was masked by the addition of Na2SO3. The system was applied in the analysis of waste water from non-ferrous-metals plants.
Copper Zinc Electrode Voltammetry Automation Interferences