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

Citations 6

"Studies On A Flow Injection System As A Tool For Online Monitoring Of Cellulose Hydrolysis And Amygdalin-containing Effluents"
Anal. Chim. Acta 1994 Volume 293, Issue 1-2 Pages 147-153
Enobong F. Umoh and Karl Schügerl*

Abstract: The FIA system for the cited online monitoring systems are both shown schematically. Cellulose hydrosylate was diluted with phosphate buffer of pH 5.5 (used throughout) and passed through the β-glucosidase cartridge (at 50°C) at 0.27 ml/min. The converted sample was injected into a phosphate buffer stream (2 ml/min) and passed through the GOD cartridge (at 30°C) to the detector. The total sugar content was calculated using the glucose-based calibration graph. A second portion of diluted hydrolysate was passed through the GOD cartridge to determine glucose. For amygdalin (toxic waste product), the effluent was diluted with phosphate buffer and injected into the carrier stream (1.7 ml/min) and passed through both enzyme columns (at 30°C) to the detector. A second portion of the diluted effluent was injected in to the carrier stream and passed through the GOD cartridge. For each analysis, the concentrations of glucose were calculated using the glucose calibration graph and amygdalin was calculated by difference.
Amygdalin Glucose

"Waste Reduction In Inductively Coupled Plasma Mass Spectrometry Using Flow Injection And A Direct-injection Nebulizer"
J. Anal. At. Spectrom. 1996 Volume 11, Issue 7 Pages 525-527
Jeffrey S. Crain and James T. Kiely

Abstract: The amount of liquid waste was compared when using flow injection direct injection nebulization (FI-DIN) and continuous pneumatic nebulization for the analysis of hazardous and/or radioactive substances by ICP-MS. After allowing the instrument to warm up for 30-60 min, a test solution containing Li, Mg, Co, Y, In, La, Lu, Pb and U was nebulized to optimize the system and test solutions of Ni and Cd and Rh as internal standard and Pb and U with Lu as internal standard were analyzed. The liquid waste (both unused sample and rinsate) was collected and the volume obtained was divided by the number of samples to obtain the waste volume per sample. Using FI-DIN the waste volume was reduced by 52%.
Mass spectrometry

"USEPA Regulation Of FIA Methods For NPDES And NIPDWR Monitoring Of Waters And Wastes"
Am. Lab. 1988 Volume 20, Issue 9 Pages 42-49
Ranger, C.B.

Abstract: A review with no references on EPA-approved flow injection analysis methods for the analysis of water and wastewater in compliance with the National Pollution Discharge Elimination System and the National Interim Primary Drinking Water Regulations.
Water Review Standard method

"Enzymically-enhanced Extraction Of Uranium From Biologically Leached Solutions"
Int. Biodeterior. Biodegrad. 1995 Volume 35, Issue 1-3 Pages 93-127
M. G. Roiga,*, T. Manzanoa, M. Díaza, M. J. Pascuala, M. Patersonb and J. F. Kennedyb

Abstract: Many wastes contain heavy metals which are toxic and refractory: further problems arise in the production and discharge of waste radionuclides which have additional radiotoxic effects on the biosphere. Currently the problem may be tackled in four ways: (i) direct chemical methods; (ii) electrochemical treatments; (iii) ion exchange and biosorption methods; (iv) intracellular sequestration by growing microbial cells. A hybrid approach exploits the advantages of processes (iii) and (iv) with the disadvantages of neither. In this context, a biotechnological process for removing and recovering heavy metals from aqueous solutions has been evaluated at low pH. Metal uptake relies upon the in situ cumulative deposition of insoluble metal phosphate tightly bound to the cell surface of Citrobacter N14. Localized high loading of phosphate is contributed via a phosphatase-catalyzed hydrolysis of an organic phosphate 'donor' molecule added to the metal solution with precipitation of metals (M) as cell-bound MHPO-4. The present work reports on the potential of this immobilized microbial biomass for uranium recovery from the dilute uranium acid drainage of ENUSA mine in the Ciudad Rodrigo district of Spain. A range of supports (organic and inorganic) and immobilization methods for Citrobacter cells have been screened. Finally, biofilm and entrapped cells on polyurethane foam and cells covalently immobilized on silanized and glutaraldehyde coated A1203 Raschig rings were chosen, characterized and evaluated for stability and suitability for large scale use. The physicochemical monitoring and chemical composition of naturally bioleached waters from ENUSA mine were evaluated and improved methods for flow injection analysis of uranium and inorganic phosphate were developed. Optimization studies of the operational conditions and performance of a plug flow bioreactor of immobilized Citrobacter for uranium removal at 30°C gave the following conclusions: (1) a working pH of 4.5 in the absence of any metal complexing agent (citrate) has been established, (2) a (glycerol 2-phosphate)/(UO-2-2+) ratio of 39 is necessary for an optimum uranium removal; (3) at a flow rate of 50 ml/h residence time of 1-4 h) the efficiency of removal was 50%. (30 references)
Uranium Ion exchange Immobilized cell Optimization

"Isolation And Analysis Of Intact Polyphosphate Chains From Activated Sludges Associated With Biological Phosphate Removal"
Water Res. 1994 Volume 28, Issue 8 Pages 1725-1733
Marica Müssig-Zufika, Anja Kornmüller, Barbara Merkelbach and Martin Jekel*

Abstract: Four extraction methods described by: (i) Psenner et al. (Arch. Hydrobiol., 1984, 111); (ii) Fitzgerald and Nelson (J. Phycol., 1966, 2, 32-37); (iii) Clark et al. (J. Bact., 1986, 168, 1212); and (iv) Mino et al. (Water Sci. Technol., 1985, 17, 11) were compared using a homogenized sample of a pure culture. FIA was used to determine total phosphate in the unfiltered sample, after digestion with K2S2O8. A HPLC system with an online detection capability was used to analyze phosphorus species (cf. Z. Wass, Abwass. Forsch., 1992, 25, 353). P1-P4 phosphates were separated on a LCA AO3 anion-exchange column (1.25 m x 4.6 mm i.d.). High mol. wt. phosphates were separated on a 5 µm LiChrospher 250 diol gel column (2.5 m x 1 cm i.d.). The eluents in both separations were EDTA/KCl. The polyphosphates were hydrolyzed to orthophosphates with HNO3 at 140°C. Then it is photometrically determined as yellow phosphorus vanadomolybdenium acid at 405 nm. Method (iv) gave the best results, 30% of the total phosphate was present as polyphosphate.
Polyphosphates HPLC Sample preparation Spectrophotometry

"Evaluation Of A Number Of Methods For The Determination Of Trace Amounts Of Phosphates With Flow Injection Analysis (FIA)"
Water SA 1997 Volume 23, Issue 2 Pages 169-174
van Staden JF; van der Merwe J

Abstract: Four different FIA/spectrophotometric analytical systems, namely tin(II) chloride (SnCl-2), ascorbic acid, malachite green and a rhodamine B methods, were optimized and evaluated in order to find the lowest detectable limit for each for the determination of trace amounts of phosphate on a routine basis. The SnCl-2 analytical system gave the best overall results. A low detection limit (2 µg/l) combined with a relatively large linear working range (1 to 400 µg/l) made this method superior to the others, The relatively unstable nature of SnCl-2 solutions together with blockages that occurred due to high concentration ranges are, however, factors to be considered when, employing the method in routine laboratories.
Phosphates Fluorescence Method comparison Optimization