Iron flow injection analysis

Eirod et al. [352] determined sub-nanomolar levels of iron (II) and total dissolved iron in seawater by flow injection analysis with chemiluminescent detection in amounts down to 0.45 nmol/1. 

Some coupled systems allow measurement of the main N and P forms (nitrate, ammonia and orthophosphates) [22,27,29], among which is a system based on membrane technology in combination with semi-micro continuous-flow analysis (pCFA) with classical colorimetry. With the same principle (classical colorimetry), another system [30] proposes the measurement of phosphate, iron and sulphate by flow-injection analysis (FIA). These systems are derived from laboratory procedures, as in a recent work [31] where capillary electrophoresis (CE) was used for the separation of inorganic and organic ions from waters in a pulp and paper process. Chloride, thiosulphate, sulphate, oxalate,... 

Gas-diffusion flow injection analysis is capable of detecting very low concentrations of chlorine dioxide in water (i.e., detection limit is 5 ppb). A chemiluminescence flow-through detector cell is used to measure the concentration chlorine dioxide as a function of chemiluminescence intensity. A gas diffusion membrane separates the donor stream from the detecting stream and removes ionic interferences from iron and manganese compounds, as well as from other oxychlorinated compounds, such as chlorate and chlorite (Hollowell et al. 1986 Saksa and Smart 1985). 

Mortatti et al. [16] has described a method for the determination of total iron in extracts of perchloric acid-nitric acid digests of plant materials. Their method involves flow injection analysis of the 1 10 phenanthroline complex. 

Pullin, M. J., and S. E. Cabaniss. 2001. Colorimetric flow-injection analysis of dissolved iron (II) and total iron in natural waters containing dissolved organic matter. Water Research 35 363-372. 

Spectrophotometric techniques combined with flow injection analysis (FIA) and on-line preconcentration can meet the required detection limits for natural Fe concentrations in aquatic systems (Table 7.2) by also using very specific and sensitive ligands, such as ferrozine [3-(2-bipyridyl)-5,6-bis(4-phenylsulfonic acid)-l,2,4-triazine], that selectively bind Fe(II). Determining Fe(II) as well as the total Fe after on-line reduction of Fe(III) to Fe(II) with ascorbic acid allows a kind of speciation.37 A drawback is that the selective complexing agents can shift the iron redox speciation in the sample. For example, several researchers have reported a tendency for ferrozine to reduce Fe(III) to Fe(II) under certain conditions.76 Most ferrozine methods involve sample acidification, which may also promote reduction of Fe(III) in the sample. Fe(II) is a transient species in most seawater environments and is rapidly oxidized to Fe(III) therefore, unacidified samples are required in order to maintain redox integrity.8 An alternative is to couple FIA with a chemiluminescence reaction.77-78... 

Al-Gailani, B.R.M., G.M. Greenway, and T. McCreedy. 2007. A miniaturized flow-injection analysis ( lFIA) system with on-line chemiluminescence detection for the determination of iron in estuarine water. Int. J. Environ. Anal. Chem. 87 637-646. 

Measures Cl, Yuan J, Resing JA (1995) Determination of iron in seawater by flow injection analysis using in-line preconcentration and spectrophotometric detection. Mar Chem 50 3-12... 

The Methylene (and Ethylene) Blue method has been applied in determinations of sulphur in plants [86], biological materials [87], waters [12,88], air [5,12,16,20], hydrocarbons [89], iron alloys [90,91], cobalt and zirconium [91], titanium [92], thallium and its halides [93], arsenic [94], selenium [95], and various reagents (including barium chloride) [14]. Flow-injection analysis has been applied in the determination of sulphur by the Methylene Blue method [96]. 

J. Alonso, J. Bartroli, M. Valle, R. Barber, Sandwich techniques in flow-injection analysis. Part 2. Simultaneous determination of iron(II) and total iron, Anal. Chim. Acta 219 (1989) 345. 

F. Lazaro, M.D. Luque de Castro, M. Valcarcel, Sequential and differential catalytic-fluorimetric determination of manganese and iron by flow injection analysis, Anal. Chim. Acta 169 (1985) 141. 

S.M.V. Fernandes, A.O.S.S. Rangel, J.L.F.C. Lima, Colorimetric determination of iron in beer by flow-injection analysis using the merging zones technique, J. Inst. Brew. 101 (1995) 281. 

Y.Z. Ye, H.Y. Mao, Y.H. Chen, Catalytic kinetic simultaneous determination of iron, silver and manganese with the Kalman filter by using flow injection analysis stopped-flow spectrophotometry, Talanta 45 (1998) 1123. 

A.P.G. Gervasio, G.C. Luca, A.A. Menegario, B.F. Reis, H. Bergamin-Filho, On-line electrolytic dissolution of alloys in flow injection analysis. Determination of iron, tungsten, molybdenum, vanadium and chromium in tool steels by inductively coupled plasma atomic emission spectrometry, Anal. Chim. Acta 405 (2000) 213. 

The spectrometric assay of iron (II) with 1,10-phenantroline is used in a flow injection analysis (FIA) for iron determination in soil.108 Iron (II) was extracted from soil samples by shaking the soil with an ammonium acetate solution (pH = 3) and the extract used for FIA determination. FIA manifold always contains a step of reduction of iron (III) to iron (II). The system can detect 60 iron samples per hour. It is a fast and reliable system for iron assay in soil. Also, it is very simple to use in every laboratory. The level of iron assay is only of milligram-per-liter magnitude, but a preconcentration step can solve this problem. 

J. Mortatti, F. J. Krug, L. C. R. Pessenda, E. A. G. Zagatto, and S. S. J0rgensen, Determination of Iron in Natural Waters and Plant Material with 1,10-Phenanthroline by Flow Injection Analysis. Analyst, 107 (1982) 659. 

T. Mochizuki, Y. Toda, and R. Kuroda, Flow Injection Analysis of Silicate Rocks for Total Iron and Aluminium. Talanta, 29 (1982) 659. 

B. F. Rocks, R. A. Sherwood, Z. J. Turner, and C. Riley, Serum Iron and Total Iron-Binding Capacity Determination by Flow Injection Analysis with Atomic Absorption Detection. Ann. Clin. Biochem., 20 (1983) 72. 

H. Wade, G. Nakagawa, and K. Ohshita, Spectrophotometric Determination of Traces of Iron with 2-(3,5-Dibromo-2-Pyridylazo)-5-[n-Ethyl-n-(3-Sulfopropyl)Amino]Phenol and its Application in Flow Injection Analysis. Anal. Chim. Acta, 153 (1983) 199. 

E. A. Jones, The Determination by Flow Injection Analysis of Iron, Sulphate, Silver and Cadmium. Techn. Rep. Mintek., Mill (1983) 32. 

T. P. Lynch, N. J. Kernoghan, and J. N. Wilson, Speciation of Metals in Solution by Flow Injection Analysis. Part 2. Determination of Iron(III) and Iron (II) in Mineral Process Liquors by Simultaneous Injection into Parallel Streams. Analyst, 109 (1984) 843. 

H. Cui and Z. Fang, Flow Injection Analysis of Iron in Soil Extracts [in Chinese]. Fenxi Huaxue, 12 (1984) 759. 

T. Sakai and N. Ohno, Flow Injection Analysis of Trace Amounts of Iron with 2-Nitroso-5-(n-Ethyl-rt-Sulfopropylamino)Phenol [in Japanese]. Bun-seki Kagaku, 33 (1984) 331. 

A. T. Faizullah and A. Townshend, Application of a Reducing Column for Metal Speciation by Flow Injection Analysis. Spectrophotometric Determination of Iron(III) and Simultaneous Determination of Iron(II) and Total Iron. Anal. Chim. Acta, 167 (1985) 225. 

F. Lazaro, M. D. Luque de Castro, and M. Valc rcel, Catalytic-Fluori-metric Determination of EDTA and Iron(III) by Flow Injection Analysis. Inhibition Methods. Fresenius Z. Anal. Chem., 321 (1985) 467. 

M. J. Whitaker and M. F. Bryant, The Determination of Pyritic Sulfur in Coal or Iron(III) in Aqueous Solutions by Flow Injection Analysis. J. Coal Qual., 4 (1985) 68. 

T. D. Yerian, T. P. Hadjioannou, and G. D. Christian, Flow-Injection Analysis with the Iron-Induced Perbromate-Iodide Reaction Spectrophoto-metric Determination of Iron. Talanta, 33 (1986) 547. 

C. Pasquini and W. A. de Oliveira, Determination of Iron in Iron Ores Using Enthalpimetric Flow Injection Analysis. Analyst, 111 (1986) 857. 

H. Muller and V. Muller, Kinetic Determination of Traces of Iron by Means of Flow Injection Analysis Based on the Catalytic Oxidation of Malachit-green Leuco Base by Hydrogenperoxide. Z. Chem., 26 (1986) 142. 

Various variables closely related to the iron determination were examined using the simple flow-injection analysis system with a fixed iron (II) concentration of 5 pg L-i. The Morin concentration was varied from IxlO M to IxlO M. The peak height was foimd to increase with increasing Morin concentration up to 1x10 M and no noticeable increase was fotmd at higher concentrations. Therefore, IxlO M Morin was decided as colour developang component of the carrier solution. 

Fig. 9. Flow diagram of the flow-injection analysis system used for the determination of iron (111) and total iron, R reagent carrier solution (IxlCH M AcSHA, IxlCH M CUSO4, pH 2.85), P, Peristaltic pump, S Rheodyne sample injection valve, MC mixing coil (50 cm long, 0.5 mm i.d), D spectrophotometric detector (kmax = 475 nm), W waste, C computer, P printer.

Bagheri H., Gholami A. and Najafi A. (2000) Simultaneous preconcentration and speciation of iron(II) and ironflfl) in water samples by 2-mercaptobenzimidazole-silica gel sorbent and flow injection analysis system. Analytica Chimica Acta, 424, 233-242. 

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