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
Email: schalk@unf.edu
Website: @unf

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Commercial product

Classification: Commercial product -> washing powder

Citations 7

"Determination Of Zeolite A In Detergent Powders As Acid-soluble Aluminum By High Performance Liquid Chromatography With Post-column Derivatization"
Anal. Chim. Acta 1981 Volume 131, Issue 1 Pages 213-222
Jiro Kawase, Atsuo Nakae and Kazuro Tsuji

Abstract: A high-performance liquid chromatographic method is described for the rapid determination of zeolite-A in detergents as acid-soluble aluminum. Detergent samples are dissolved by digestion with nitric acid. Chromatographic separation on a strong cation exchanger in acidic ammonium sulfate media is combined with the highly selective color reaction of acid-soluble aluminum with pyrocatechol violet. Interferences of the chelating agents in detergents are thus eliminated. After the digestion, determinations take 8 min per sample. The relative standard deviation is less than 1% and quantitative recoveries are obtained. Several commercial detergents were analyzed successfully. The results obtained by the proposed method and by complexometric titration agreed very closely for zeolite-A contents in the range 2-22%.
Aluminum Zeolite A HPLC Post-column derivatization

"Flow Injection Determination Of Phosphate Species In Detergents With A Calcium Ion-selective Electrodes"
Anal. Chim. Acta 1987 Volume 197, Issue 1 Pages 353-359
Peter W. Alexander and Javapa Koopetngarm

Abstract: The flow injection manifolds were made of polyethylene tubing (i.d. 1.14 mm) and an Omnifit T-connector in a two-channel system. The sample solution (0.25 ml), containing citrate, EDTA, pyrophosphate or tripolyphosphate(I), was injected into a carrier stream (4.75 mL min-1) of 50 mM Na2B4O7 buffer and then mixed with a buffered stream of 0.1 mM Ca at the T-junction before reaching the Ca(II)-selective electrode. The calibration graph was rectilinear for 0.1 to 10 mM I and results agreed with those obtained by HPLC. Results are presented for the other ligands.
Citrate EDTA Pyrophosphate Tripolyphosphate Electrode Potentiometry Method comparison

"Multi-site Detection In Flow Analysis. 3. Periodate Tubular Electrode With Low Inner Volume As A Relocatable Detector"
Anal. Chim. Acta 1994 Volume 285, Issue 3 Pages 293-299
José A. Gomez Neto, Ana Rita A. Nogueira, H. Bergamin Filho and Elias A. G. Zagatto*, José L. F. Costa Lima and Conceição B. S. M. Montenegro

Abstract: The membrane sensor comprised 30% PVC, 63% o-nitrophenyl octyl ether and 7% tetra-octylammonium periodate, with an inner volume of 45 µL. Its position could be changed with use of an electronic commutator, to which were attached the working and Ag/AgCl reference electrodes. Two configurations are described. In one, used for the determination of glycerol, the sensor could be moved to either of two identical channels. Glycerol solution (30 µL) were injected into a reagent carrier of 3 mM NaIO4, 0.5 M Na2SO4, 0.1 M acetic acid and 0.1 M sodium acetate (0.5 ml/min). The carrier passed through a coiled reactor (1 m x 0.7 mm i.d.) to the sensor, where unconsumed periodate was measured. Calibration graphs were linear for 0.05-0.2% glycerol. The commutator was switched to the parallel channel a few s after the peak maximum was reached, thus the sampling rate of 100/h was not affected by the wash-out time. For sucrose, the sensor was moved to a position downstream in the same channel. Calibration graphs were linear for 0.1-0.5% sucrose. Glycerol was determined in soaps and detergents, and sucrose was determined in sugar cane juice and syrups.
Glycerol Sucrose Electrode Sensor Apparatus Detector

"Flow Injection Determination Of Anionic Surfactants Based On The Solvatochromism Of P-diphenylaminoazobenzene Sulfonate"
Anal. Chim. Acta 1997 Volume 343, Issue 1-2 Pages 33-37
Jingfu Liu*

Abstract: The flow injection spectrophotometric method for determining anionic surfactants was based on the increase in absorbance of the p-diphenylaminoazobenzene sulfonate (PDABS)/Triton X-100 (T- x 100)/hexadecyltrimethylammonium bromide (CTAB) system at 530 nm in the presence of an anionic surfactant. Sample (200 µL) was injected into a water carrier stream (1.8 ml/min) which was then merged with a reagent stream formed online by merging CTAB/200 µg/ml T- x 100 (0.9 ml/min) and PDABS (0.9 ml/min). The mixture was passed through a reaction coil (100 cm x 0.5 mm i.d.) to the detector cell where the absorbance was monitored. The concentration of PDABS was 0.12-0.2 mM and was 20% greater than the concentration of CTAB. The determination was carried out at pH 1. Linear calibration graphs were obtained for five different anionic surfactants for up to 40 µM. The RSD (n = 11) for 20 µM-sodium dodecylbenzenesulfonate (DBS) was 0.9%. The detection limits for DBS and SDS were 0.2 µM. The method was applied to washing powders and the results were confirmed by the Epton titrimetric method.
Surfactants, anionic Spectrophotometry Triton X Method comparison Surfactant Solvatochromic

"Static And Flow Injection Voltammetric Determination Of Total Phosphate And Soluble Silicate In Commercial Washing Powders At A Glassy Carbon Electrode"
Analyst 1983 Volume 108, Issue 1293 Pages 1485-1489
Arnold G. Fogg, Geoffrey C. Cripps and Brian J. Birch

Abstract: The lowering effect of anionic detergents on the differential-pulse voltammetric peak currents obtained for 12-molybdophosphate and 12-molybdosilicate in aqueous solution was avoided when aqueous 50% ethanol or aqueous 50% acetone was used as test medium. Static differential-pulse voltammetric and flow injection voltammetric procedures have been devised for determination of total phosphate (involving hydrolysis of phosphates) and of soluble silicate in commercial washing powders. The results are compared with those obtained by the molybdenum blue colorimetric procedure. The effect of increases in the concentration. of ethanol and acetone was studied. No mutual interference between phosphate and silicate was observed.
Phosphate Silicate Polyphosphates Electrode Voltammetry Interferences

"Determination Of Polyphosphates In Intermediate Materials For Detergent Manufacture By Ion High Performance Liquid Chromatography With Post-column Derivatization"
J. Chromatogr. A 1991 Volume 585, Issue 2 Pages 267-271
P. Linares, M. D. Luque de Castro* and M. Valcárcel

Abstract: Intermediate material was dissolved in 0.1 M KCl and portions of the solution were analyzed with a flow injection system by injection into a stream of 0.1 or 0.2 M KCl (pH 9) containing 1 mM Na4EDTA. The stream was directed to a pre-column of Ion-Guard GA-100 and then to a column (12 cm x 4.6 mm) of Ion-120. The eluate was hydrolyzed with a stream of 3 M H2SO4 after which the stream was heated at 90°C. For derivatization of PO43- and pyro-, tripoly- and trimeta-phosphate, an online stream of 2% ascorbic acid and 5% Na2MoO4 in 3 M NaOH was merged with the sample stream. The derivatives were detected at 820 nm.
Polyphosphates HPIC LC Spectrophotometry Heated reaction Post-column derivatization

"FIA Of Non-ionic Surfactants Using A Plasticized Poly(vinyl Chloride)-membrane Electrode And A Micro-column Packed With An Ion-exchange Resin"
Bunseki Kagaku 1991 Volume 40, Issue 1 Pages 7-11
Masadome, T.;Imato, T.;Ishibashi, N.

Abstract: An FIA system was proposed for determining non-ionic surfactants which incorporates an ion-exchange resin column, aqueous 50% methanol as mobile phase and a plastizized poly(vinyl chloride)-membrane electrode as detector. The calibration graph was rectilinear from 40 to 500 µM-Triton X-100 and the detection limit was 10 µM. Inorganic electrolytes did not interfere. The method was applied in the analysis of detergents.
Surfactants, non ionic Electrode Ion exchange Column Interferences Resin Triton X Surfactant