Uses of electrochemical systems in environmental control technology are described for the removal and separation of metals from solution and the destruction of dye molecules in effluents. A novel concentrator cell system for the removal of lead and cadmium from solution is developed. The operation of this system permits the pH-independent recovery of metals from solution by electrodeposition. The formation of complexes with suitable ligands is exploited to achieve the separation of metals by electrochemical methods. The separations of tin, lead and indium from each other, the separation of nickel from cobalt and the separation of copper and palladium from cobalt are used to illustrate the benefits of complex formation. A three-compartment electrodialysis cell for removal of nickel from cobalt exploiting the greater stability of the nickel-EDTA complex compared with the Co-EDTA complex is described. Efficient removal of nickel from cobalt can be achieved but there is a compromise between cobalt purity and the percentage of cobalt transferred to the catholyte chamber for recovery. The anodic oxidation of a number of dye molecules including methylene blue, acid blue 25, reactive blue 2 and reactive blue 15 in chloride solution has been studied. The anodic oxidation of methylene blue results in the formation of seven neutral and two charged intermediates. The main intermediate is identified by X-ray diffraction crystal structure determination and accurate mass spectrometry as the novel compound 4,6-dichloro-7-dimethylamino-3H-phenothiazin-3 -one, (C14HjoCI2N20S) formed by replacement of one of the diirnethylamino groups of methylene blue with oxygen accompanied by regiospecific chlorination of the carbocylic system. The mass spectra of other intermediates formed are interpreted in terms of this structure. An electroadsorption system combining adsorption and electrolytic processes to achieve the elimination of the chlorinated compounds that are formed during the electro-oxidation of methylene blue is also reported.

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Lipase, from porgy (Stenotomus chrysops) viscera, was purified by polyethylene glycol (PEG) 1000 precipitation, followed by dialysis and affinity chromatography on EAH-Sepharose 48. The digestive lipase from porgy showed seasonal variation in activity with high activity found in late summer and early fall compared with a spring sample. Polyethylene glycol (PEG) precipitation fraction was used to characterize this enzyme using p-nitrophenyl palmitate (pNPP) as substrate. Porgy lipase did not behave like a bile salt activated/depended lipase because it was able to hydrolyze pNPP without bile salt (e.g., sodium cholate). Porgy lipase was stable within the pH range of pH 6.0-10.0, with an optimum activity at pH 8.5. The enzyme was quite stable at temperatures below 40°C, but lost its activity rapidly at temperatures above 40°C. The optimum activity for hydrolysis pNPP was at 40°C, but the enzyme also demonstrated relatively high activity at temperatures below 40°C (i.e., 10-40°C) as well. Detergents, Triton X-100, Tween 40 and Tween 80, at final concentrations of 0.5 mM and 1 mM were found to have inhibitory effects on porgy digestive lipase activity. However, all three tested detergents appeared to increase the activity of porgy digestive lipase at elevated temperatures (i.e., 60-80°C).

The objective of this research was to develop new molecular sieve materials and to examine their applications in adsorptive gas separation processes. Several techniques to modify zeolite molecular sieve materials were developed, including a new pore size control mechanism and novel surface modification procedures. The new materials derived from these modification techniques were found to be potentially useful in many adsorptive gas separation processes. A novel mechanism was developed to systematically control the pore size of titanium silicate molecular sieves through halogen substitution of terminal hydroxyl groups. These halogen containing zorites represent a new class of size-selective adsorbents with readily tailored and highly specific pore sizes. Anion-controlled titanium silicates were demonstrated to have promise in multiple areas of size-based separation, particularly light hydrocarbon purification and permanent gas separation. By controlling the type and quantity of the extra-framework cations, titanium silicate molecular sieve adsorbents were modified to separate ethylene and ethane by either the kinetic phenomenon or an equilibrium process. All of these modification techniques were synergistically integrated to illustrate that multi-functional adsorbents can be designed and prepared for many target separations. This approach was demonstrated through the separations of CO2/C2H6 and CO2/CH4. Anion-controlled adsorbents were modified to selectively exclude ethane and methane by the steric effect, while the equilibrium and kinetic properties of the adsorbents were concomitantly adjusted by surface modification. The concept of gas adsorption and separation through nanometals interaction was introduced. Surface-supported nanometals, such as nanosilver, formed on titanium silicate ETS-10 were applied as unique adsorbents to separate gas mixtures, such as Ar/O2 and N2/O2. Continual research and development in new molecular sieve materials will be crucial to the future of the chemical processing industry, and should be viewed as an avenue for the discovery of next-generation adsorptive gas separation technologies. / Chemical Engineering

Thesis (Ph.D.) -- McMaster University, 1997. / Includes bibliographical references Also available via World Wide Web.

Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references (leaves 74-82). Also available in electronic version.

Thesis (Ph. D.)--University of New South Wales, 2002. / Also available online.

Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1897. / The entire thesis text is included in file. Typescript. Illustrated by authors. Jno. Rogers determined to be John A. Rogers and G. W. Dean determined to be George Walter Dean from "Forty-First Annual Catalogue. School of Mines and Metallurgy, University of Missouri". Title from title screen of thesis/dissertation PDF file (viewed February 12, 2009)