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 -> sewage

Citations 8

"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. Kühl, 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

"Determination Of Trace Amounts Of Heavy Metals In Waters By A Flow Injection System Including Ion-exchange Preconcentration And Flame Atomic Absorption Spectrometric Detection"
Anal. Chim. Acta 1984 Volume 164, Issue 1 Pages 41-50
Zhaolun Fang, Shukun Xu and Suchun Zhang

Abstract: The flow injection system described (see preceding abstract) has been applied to the determination of Ni, Cu, Pb and Cd. The samples (5 ml) were injected into a stream of 0.1 M ammonium acetate (pH 5.5) via a sampling loop, and the solution was passed through two columns (50 mm x 2.5 to 3 mm) filled with a chelating ion-exchange resin containing a salicylic acid functional group. Elution was effected with 2 M HNO3, and Ni, Cu, Pb and Cd were determined in the eluate by AAS, with absorption measurements at 232.0, 324.8, 283.8 and 228.8 nm, respectively, and use of an air - acetylene flame. At a sampling rate of 40 h-1, the sensitivity was enhanced 20 to 28-fold in comparison with that attained by direct aspiration of the sample solution into the flame. With the exception of Cd, recoveries of the metals from sewage, tap-water and seawater were generally satisfactory; coefficient of variation were generally 4.1% (n = 11).
Metals, heavy Cadmium Copper Lead Nickel Ion exchange Spectrophotometry Chelation Resin Preconcentration

"New Approach To The Simultaneous Determination Of Pollutants In Waste Water By Flow Injection Analysis. 1. Anionic Pollutants"
Analyst 1984 Volume 109, Issue 11 Pages 1487-1492
Angel Ríos, M. Dolores Luque de Castro and Miguel Valcárcel

Abstract: The general manifold described, which operates on the principle of reversed-flow injection, incorporates several injection valves that permit the insertion of specific reagents for the spectrophotometric determination of each species at different points in the waste-water stream. By positioning a glass - calomel micro-electrode in front of these valves, the pH can be monitored continuously. A single detector is used for analytes undergoing reaction, thereby allowing the concentration. of several pollutants in the sample to be measured at any moment without prior treatment. The scheme is simple, rapid and versatile and has been satisfactorily applied to the concurrent determination of S2- and CN- (and pH) and of NO2- and CN- (and pH). The NO2- determination is the most selective, S2- being the most significant interfering species; NO2- also interferes in the determination of S2-
Cyanide Nitrite pH Sulfide Electrode Potentiometry Spectrophotometry Interferences Process control Reverse

"Optical Fibre Sensor For Biological Oxygen Demand"
Anal. Chem. 1994 Volume 66, Issue 11 Pages 1841-1846
Claudia Preininger, Ingo Klimant, and Otto S. Wolfbeis

Abstract: The cited biosensor (illustrated) comprised a sensing membrane mounted at the tip of an optical fiber. The membrane consisted of an optically-transparent gas-permeable polyester support on which layers of tris[4,7-diphenyl-1,10-phenanthroline]ruthenium(II) perchlorate (an O2-sensitive fluorescent material), charcoal (as an optical isolator), yeast cells (Trichosporon cutaneum) immobilized in poly(vinyl alcohol) and a substrate-permeable polycarbonate membrane were sequentially placed. The sensor was incorporated in a continuous-flow system with a 150 W pulsed Xe light source and a photomultiplier as detector; a 480 nm interference filter was used to isolate the appropriate excitatory light and a 560 nm long-pass filter was used to collect the red fluorescence (λmax = 610 nm). The calibration graph was linear for a BOD of up to 110 mg/l for a glucose/glutamate standard and the detection limit was ~2-3 mg/l; the RSD was 4%. The response time was 5-10 min. The method was applied to untreated sewage plant effluents and the results correlated well with those obtained by the conventional dilution method.
Glucose Glutamate Biological oxygen demand Sensor Fluorescence Optical fiber Method comparison Immobilized cell Interferences

"Spectral And Non-spectral Interferences In Inductively Coupled Plasma Mass Spectrometry"
Microchim. Acta 1995 Volume 119, Issue 3-4 Pages 277-286
Richard F. J. Dams, Jan Goossens and Luc Moens

Abstract: An overview is presented on the identification and elimination of interferences in ICP-MS. Elimination of spectral interferences by anion exchange, matrix modification and mathematical correction are discussed. Calibration methods, adapted sample preparations and flow injection techniques for the elimination of nonspectral interferences are then considered. Applications of the correction methods to the analysis of water, soil, sewage, urine, serum and wine are described. (50 references).
Mass spectrometry Sample preparation Interferences Matrix removal Review

"Semiautomated Determination Of COD In Wastewater Samples"
Mem. Sch. Eng. Okayama Univ. 1980 Volume 14, Issue 2 Pages 119-129
Korenaga Takashi;Ikatsu Hisayoshi;Ikatsu Hisayoshi;Moriwake Toshio;Takahashi Teruo

Abstract: A new method based on the principle of flow injection analysis is presented for the semiautomated determination of chemical oxygen demand (COD) in environmental water samples. The method is rapid and continuous, and suitable for the monitoring of COD in wastewaters. The apparatus used was simply constructed by parts commercially available for high performance liquid chromatography. Teflon tubing heated with a boiling watAr was used as a reactor and simultaneously used for mixing coils and transmission lines. The operating conditions were examined to apply the determination of COD in wastewaters by using glucose as a standard COD substance. The procedures recommended are as follows: Both 4.9 x l0-4 M potassium permanganate and 6. 7 % sulfuric acid solutions are individually pumped, 20 pL of a sample solution is injected into the flow of the sulfuric acid solution, and then mixed with a mixing joint. The mixed solution is transported to a flow cell situated in a spectrophotometer fixed at a wavelength of 525 nm, and decrements of absorbance are recorded. The peaks were reproducibly obtained at a concentration-range of 10^-200 mg-COD 1 L-1. Chloride up to 1000 mg L-1 was not interfered at all. Various wastewater samples were analyzed by the proposed method at a sampling rate of 30 samples .per hour, and the apparent COD values obtained were compared with the manual COD ones obtained by JIS method.
Chemical oxygen demand Spectrophotometry Interferences Method comparison Standard method

"Initial Studies On The Use Of High Performance Liquid Chromatography For The Rapid Assessment Of Sewage-treatment Efficiency"
Water Res. 1984 Volume 18, Issue 8 Pages 955-961
Leslie Brown*, Michael M. Rhead and James Braven

Abstract: Samples were collected from a sewage treatment plant and filtered (0.45 µm); aliquots (10 to 100 µL) were analyzed for polar dissolved organic compounds by HPLC on a column (25 cm x 5 mm) of Hypersil ODS with aqueous 0.02% H3PO4 (pH 2.65) or 0.01 M NaH2PO4 - Na2HPO4 (pH 7.5) as the mobile phase (2 mL min-1) and detection at 215, 230 and 287 nm; aromatic compounds and amino-acids (after post-column derivatization) were detected fluorimetrically at 320 and 440 nm (excitation at 254 and 345 nm), respectively. The results were in good agreement with those obtained by conventional methods.
Amino Acids HPLC Fluorescence Post-column derivatization

"Rapid Method For Separating And Quantifying Orthophosphate And Polyphosphates Application To Sewage Samples"
Water Res. 1998 Volume 32, Issue 3 Pages 711-716
D. Jolley, W. Maher,* and P. Cullen

Abstract: A method was devised to separate and quantify the concentrations of orthophosphate and polyphosphates (tripolyphosphate and pyrophosphate) in sewage samples. Phosphate species were separated by anion exchange chromatography using Dowex 1-X8 resin (100-200 mesh, Cl- form). The use of a 0.2 M KCl/acetate buffer (pH 4.5) solution (100 mL) to elute orthophosphate and a 0.4 M KCl/ acetate buffer (pH 4.5) solution (100 mL) to elute polyphosphates, quantitatively eluted phosphorus from the resin. Recoveries of 97±2% for orthosphosphate and 98±3% for polysphosphates were achieved for a variety of mixtures of orthophosphate, tripolyphosphate and pyrophosphate. Recoveries of orthophosphate and tripolyphosphate added to sewage were 95-97% and 88% respectively. The use of EDTA in eluents as used in previous studies was found to cause an interference when phosphorus was quantified using the phosphoantimonylmolybednum blue method. Analysis of centrifuged raw sewage samples revealed that phosphorus was present mainly as orthophosphate, no polyphosphates were detected. It is likely that polyphosphates are hydrolyzed prior to entering sewers because of extreme pH and temperatures encountered during clothes and dishwashing or in sewers by bacteria or cations. (15 References)
Tripolyphosphate Polyphosphates Phosphate Pyrophosphate HPIC EDTA