This thesis is concerned with investigating the suitability of room temperature ionic liquids as solvents in which to perform voltammetry, and in characterising electrochemical processes within these media. After providing a general introduction and a background to the ionic liquid field, the results of six original studies are presented, dealing in turn with the following subjects: • The oxidation of N,N,N',N'-tetraalkyl-para-phenylenediamine (TAPD) in five ionic liquids each incorporating the bis(trifluoromethylsulfonyl)imide anion. • The reduction of oxygen in four ionic liquids based on quaternary alkyl -onium cations and heavily fluorinated anions in which the central ion is either nitrogen or phosphorous. The simulation of double potential step chronoamperometry at a disk electrode for the case of unequal diffusion coefficients and its experimental validation using a variety of aqueous, traditional nonaqueous and ionic liquid solutions. • The rate of diffusion of N,N,N',N'-tetramethyl-para-phenylenediamme (TMPD), its radical cation and dication as a function of temperature and ionic liquid viscosity and four such solvents. • The temperature dependence of the viscosity of five ionic liquids along with the translational and rotational diffusion coefficients of dissolved 2,2,6,6- tetramethylpiperidine-N-oxyl (TEMPO). • The kinetics of the reaction between N,N-dimethyl-para-toluidine (DMT) and its electrogenerated radical cation in an ionic liquid solvent. The experimental strategy common to each report involves the application of cyclic voltammetry and chronoamperometry at disk electrodes immersed in uL-samples of ionic liquid solution. The data so measured is then analysed via the appropriate theoretical equations or, as is commonly necessary, by comparison with simulated voltammetry. Combined, these chosen redox systems provide access to information on various aspects of electrochemistry within ionic liquids, specifically (a) mass transport (b) the nature of the electron transfer process and (c) the rate of follow-up homogeneous reactions. It is the overall finding herein that while both diffusion and heterogeneous electron transfer are significantly slowed relative to the same processes in a conventional organic solvent, the rate of subsequent homogeneous chemistry remains largely unchanged.

Ionic liquids (ILs) were studied as solvents for electrochemical reactions with the intent to devise metallurgical processes for Al, Mg and Ti that are less energy intensive and operate at lower temperatures than current industrial practice. Tetra-alkyl phosphonium ILs are on the low end of the IL cost spectrum and are regarded as understudied compared with imidazolium and pyridinium ILs. They are also known to be more thermally stable. The density, viscosity and conductivity of the phosphonium ILs and metal salt-IL mixtures were measured. The conductivity of the phosphonium ILs tested were found to be roughly an order of magnitude lower than imidazolium ILs; this is attributed to the relatively large cation size and localized charge. Linear density-temperature functions are presented. The viscosity and conductivity temperature relationship was modeled using the Vogel-Tamman-Fulcher (VTF) equation. The electrochemical window of A10341'14,6,6,610 was studied on a Pt substrate over a wide range of A1C13 concentrations using cyclic voltammetry (CV). It was found that the tetra-alkyl phosphonium cation is on the order of 800 mV more electrochemically stable than the 1-ethyl-3-methyl imidazolium (EMI+). Cathodic and anodic polarization of Al in A1C13-[P14,6,6,6]C1 (Xmc13 = 0.67) was studied at temperatures ranging from 347 to 423 K. The Butler-Volmer equation was fitted to the plots by varying the kinetic parameters. The cathodic reaction was found to be diffusion limited and the anodic reaction is limited by passivation at lower temperatures. The overpotential required for electrodissolution of Al was found to be higher than for electrodeposition. Aluminium was electrodeposited using both an electrowinning setup (chlorine evolution anode reaction) and electrorefining setup (Al dissolution anode reaction). The deposits were characterized in terms of morphology, current efficiency and power consumption. A variety of deposit morphologies were observed ranging from smooth, to spherical to dendritic, and in some cases, the IL was occluded in the deposit. The current efficiency and power consumption were negatively impacted by the presence of H2O and HCl present in the as-received ILs and by C12(g) generated by the anode reaction in the case of the electrowinning setup. HC1 was removed by cyclic polarization or corrosion of pure Al, resulting in current efficiencies above 90%. Aluminium was electrodeposited using the electrorefining setup with anode-cathode spacing of 2 mm at power consumption as low as 0.6 kWhr/kg-Al. This is very low compared with industrial Al electrorefining and Al electroplating using the National Bureau of Standards bath, which require 15-18 kWhr/kg-Al and 18 kWhr/kg-Al, respectively. However, due to low solution conductivity the power consumption increases significantly with increased anode-cathode spacing. Titanium tetrachloride was found to be soluble in [P14,6,6,6]Cl and increases the conductivity of the solution. Attempts to reduce the Ti(IV) included corrosion of titanium metal, corrosion of magnesium metal powder and cathodic polarization. Despite a few attempts, the electro-deposition of Ti was not observed. At this point, titanium electrodeposition from phosphonium based ILs does not appear feasible.

Sorption of non-ionic organic compounds to organic matter is usually characterized as a partitioning interaction, which is quantified by K [subscript]oc, the organic-C normalized partitioning coefficient. However K [subscript]oc for any single compound varies considerably between soils, often by a factor of 3-10. This study addresses some of the potential causes of this variability. Forty-four soil cores were collected from a 2 ha paddock. Ten of these cores were selected for sorption measurements. The chemical composition of the soil organic matter (SOM) was determined using ¹³C NMR analysis. It was found that K [subscript]oc for diuron was positively correlated with aryl C (r² = 0.59) and negatively correlated with O-alkyl C (r² = 0.84). There were no such correlations for phenanthrene K [subscript]oc. A second set of experiments was carried out to investigate the effects of SOM– mineral interactions on the sorption properties of a selection of the soils. It was found that HF-treatment increased K [subscript]oc for both phenanthrene and diuron. The HF treatment removes mineral matter leaving the organic phase unaffected by the treatment. The increase in K [subscript]oc on HF-treatment soils provides strong evidence that interactions between organic matter and soil minerals block organic matter sorption sites. Furthermore, following HF-treatment, there was a positive correlation between K [subscript]oc for phenanthrene and aryl C and carbonyl C and a negative correlation with O-alkyl C. This suggests that the non-constancy of the relationship between organic matter chemistry and K [subscript]oc, for whole soils in the case of phenanthrene, may be a consequence of variability of the effect of organic matter-mineral interactions on K [subscript]oc. The influence of lipids on the sorption of diuron and phenanthrene to soils was also investigated. Lipids are known to cover the surfaces of organic matter in soil. K [subscript]oc for diuron and phenanthrene were consistently higher for the lipid-extracted soils than for the whole soils (average of 31% for diuron and 29% for phenanthrene), indicating that lipids block sorption sites on the organic matter. Sorption experiments on one pair of HF-treated soils indicated that the blocking effects of minerals and lipids are independent, because lipid extraction and HF-treatment combined increased K [subscript]oc by more than either treatment alone. In the last experiment, the effect of solvent conditioning on the sorption of diuron and phenanthrene was investigated. The K [subscript]oc values for compounds were consistently higher for solvent-treated whole soil and lipid-extracted soil than corresponding soils before solvent treatment. Solid-state ¹³C NMR spectra of the solvent-treated soils indicated that there were no significant changes in the chemical structure of SOM caused by solvent treatment. Solvent treatment changes the physical conformation of the SOM, increasing its sorption affinity. The key findings from the research are: • Variations in sorption affinity for diuron are related to differences in the soil organic matter chemistry. • SOM-mineral interactions can have a substantial influence on K [subscript]oc for non- ionic compounds. • Lipids may block the active sorption sites on the SOM thereby diminishing sorption overall. • Solvent conditioning can change the physical conformation of SOM and lead to enhancement sorption of diuron and phenanthrene. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1372068 / Thesis (Ph.D.) - University of Adelaide, School of Earth and Environmental Sciences, 2009

Sorption of non-ionic organic compounds to organic matter is usually characterized as a partitioning interaction, which is quantified by K [subscript]oc, the organic-C normalized partitioning coefficient. However K [subscript]oc for any single compound varies considerably between soils, often by a factor of 3-10. This study addresses some of the potential causes of this variability. Forty-four soil cores were collected from a 2 ha paddock. Ten of these cores were selected for sorption measurements. The chemical composition of the soil organic matter (SOM) was determined using ¹³C NMR analysis. It was found that K [subscript]oc for diuron was positively correlated with aryl C (r² = 0.59) and negatively correlated with O-alkyl C (r² = 0.84). There were no such correlations for phenanthrene K [subscript]oc. A second set of experiments was carried out to investigate the effects of SOM– mineral interactions on the sorption properties of a selection of the soils. It was found that HF-treatment increased K [subscript]oc for both phenanthrene and diuron. The HF treatment removes mineral matter leaving the organic phase unaffected by the treatment. The increase in K [subscript]oc on HF-treatment soils provides strong evidence that interactions between organic matter and soil minerals block organic matter sorption sites. Furthermore, following HF-treatment, there was a positive correlation between K [subscript]oc for phenanthrene and aryl C and carbonyl C and a negative correlation with O-alkyl C. This suggests that the non-constancy of the relationship between organic matter chemistry and K [subscript]oc, for whole soils in the case of phenanthrene, may be a consequence of variability of the effect of organic matter-mineral interactions on K [subscript]oc. The influence of lipids on the sorption of diuron and phenanthrene to soils was also investigated. Lipids are known to cover the surfaces of organic matter in soil. K [subscript]oc for diuron and phenanthrene were consistently higher for the lipid-extracted soils than for the whole soils (average of 31% for diuron and 29% for phenanthrene), indicating that lipids block sorption sites on the organic matter. Sorption experiments on one pair of HF-treated soils indicated that the blocking effects of minerals and lipids are independent, because lipid extraction and HF-treatment combined increased K [subscript]oc by more than either treatment alone. In the last experiment, the effect of solvent conditioning on the sorption of diuron and phenanthrene was investigated. The K [subscript]oc values for compounds were consistently higher for solvent-treated whole soil and lipid-extracted soil than corresponding soils before solvent treatment. Solid-state ¹³C NMR spectra of the solvent-treated soils indicated that there were no significant changes in the chemical structure of SOM caused by solvent treatment. Solvent treatment changes the physical conformation of the SOM, increasing its sorption affinity. The key findings from the research are: • Variations in sorption affinity for diuron are related to differences in the soil organic matter chemistry. • SOM-mineral interactions can have a substantial influence on K [subscript]oc for non- ionic compounds. • Lipids may block the active sorption sites on the SOM thereby diminishing sorption overall. • Solvent conditioning can change the physical conformation of SOM and lead to enhancement sorption of diuron and phenanthrene. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1372068 / Thesis (Ph.D.) - University of Adelaide, School of Earth and Environmental Sciences, 2009

Sorption of non-ionic organic compounds to organic matter is usually characterized as a partitioning interaction, which is quantified by K [subscript]oc, the organic-C normalized partitioning coefficient. However K [subscript]oc for any single compound varies considerably between soils, often by a factor of 3-10. This study addresses some of the potential causes of this variability. Forty-four soil cores were collected from a 2 ha paddock. Ten of these cores were selected for sorption measurements. The chemical composition of the soil organic matter (SOM) was determined using ¹³C NMR analysis. It was found that K [subscript]oc for diuron was positively correlated with aryl C (r² = 0.59) and negatively correlated with O-alkyl C (r² = 0.84). There were no such correlations for phenanthrene K [subscript]oc. A second set of experiments was carried out to investigate the effects of SOM– mineral interactions on the sorption properties of a selection of the soils. It was found that HF-treatment increased K [subscript]oc for both phenanthrene and diuron. The HF treatment removes mineral matter leaving the organic phase unaffected by the treatment. The increase in K [subscript]oc on HF-treatment soils provides strong evidence that interactions between organic matter and soil minerals block organic matter sorption sites. Furthermore, following HF-treatment, there was a positive correlation between K [subscript]oc for phenanthrene and aryl C and carbonyl C and a negative correlation with O-alkyl C. This suggests that the non-constancy of the relationship between organic matter chemistry and K [subscript]oc, for whole soils in the case of phenanthrene, may be a consequence of variability of the effect of organic matter-mineral interactions on K [subscript]oc. The influence of lipids on the sorption of diuron and phenanthrene to soils was also investigated. Lipids are known to cover the surfaces of organic matter in soil. K [subscript]oc for diuron and phenanthrene were consistently higher for the lipid-extracted soils than for the whole soils (average of 31% for diuron and 29% for phenanthrene), indicating that lipids block sorption sites on the organic matter. Sorption experiments on one pair of HF-treated soils indicated that the blocking effects of minerals and lipids are independent, because lipid extraction and HF-treatment combined increased K [subscript]oc by more than either treatment alone. In the last experiment, the effect of solvent conditioning on the sorption of diuron and phenanthrene was investigated. The K [subscript]oc values for compounds were consistently higher for solvent-treated whole soil and lipid-extracted soil than corresponding soils before solvent treatment. Solid-state ¹³C NMR spectra of the solvent-treated soils indicated that there were no significant changes in the chemical structure of SOM caused by solvent treatment. Solvent treatment changes the physical conformation of the SOM, increasing its sorption affinity. The key findings from the research are: • Variations in sorption affinity for diuron are related to differences in the soil organic matter chemistry. • SOM-mineral interactions can have a substantial influence on K [subscript]oc for non- ionic compounds. • Lipids may block the active sorption sites on the SOM thereby diminishing sorption overall. • Solvent conditioning can change the physical conformation of SOM and lead to enhancement sorption of diuron and phenanthrene. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1372068 / Thesis (Ph.D.) - University of Adelaide, School of Earth and Environmental Sciences, 2009

In recent years there has been increasing interest in novel forms of surfactants. Of particular interest are gemini surfactants, which consist of two conventional surfactants joined by a spacer at the head groups, as they exhibit lower critical micelle concentrations than can be achieved by conventional surfactants. In this work, the self-assembly behaviour of several nonionic gemini surfactants with polyethylene oxide head groups (GemnEm, where n (= 20) is the number of carbons per tail and m (= 10, 15, 20 and 30) is the number of ethylene oxides per head group) were investigated. The Critical Micelle Concentrations (CMCs) were measured using a fluorescence probe technique. The CMCs are all ~2 x 10?7 M, with almost no variation with m. The CMCs are several orders of magnitude lower than conventional C12Em nonionic surfactants. The mixing behaviour of the gemini surfactants with conventional surfactants was also studied. They obeyed ideal mixing behaviour with both ionic and nonionic surfactants. Micelle morphologies were studied using Small Angle Neutron Scattering. The gemini surfactants with the larger head groups (i.e. Gem20E20 and Gem20E30) formed spherical micelles. Gem20E15 showed strong scattering at low Q, characteristic of elongated micelles. As the temperature was increased towards the cloud point, the scattering approached the Q-1 dependence predicted for infinite, straight rods. The existence of anisotropic micelles was supported by the viscosity of Gem20E15, which increases by several orders of magnitude on heating towards its cloud point. Phase behaviour was determined using Diffusive Interfacial Transport coupled to near-infrared spectroscopy. Much of the behaviour of these systems is similar to conventional nonionic surfactants. For example, Gem20E10 forms a dilute liquid isotropic phase (W) coexisting with a concentrated lamellar phase (La) at around room temperature and forms a sponge phase at higher temperatures. This is similar to the behaviour of C12E3 and C12E4. The other surfactants studied are all quite soluble in water and form liquid isotropic and hexagonal phases from room temperature. At higher concentrations Gem20E15 formed a cubic and then a lamellar phase while Gem20E20 formed a cubic phase and then an intermediate phase. This is also comparable to the phase behaviour of conventional nonionic surfactants except the intermediate phase, which is often only observed for surfactant systems with long alkyl tails.

Thesis (M.Ch.E.)--University of Delaware, 2008. / Principal faculty advisors: Norman J. Wagner, Dept. of Chemical Engineering; and Eric W. Kaler, College of Engineering. Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Οι ζεόλιθοι είναι μικροπορώδεις αργιλοπυριτικές κρυσταλλικές ενώσεις οι οποίες αποτελούνται απο τετράεδρα SiO4 και AlO4 που σχηματίζουν κρυσταλλικά πλέγματα σε μία, δύο ή τρείς διαστάσεις. Εξαιτίας των μοναδικών φυσικοχημικών ιδιοτήτων τους, οι ζεόλιθοι σήμερα χρησιμοποιούνται σε ένα μεγάλο πλήθος εφαρμογών τόσο σε βιομηχανικό όσο και σε εργαστηριακό επίπεδο. Από την άλλη μεριά, ώς ιονικά υγρά ορίζονται οι ιοντικές ενώσεις (άλατα) εκείνες οι οποίες στη θερμοκρασία δωματίου βρίσκονται στην υγρή φάση. Η αμελητέα τάση ατμών, το χαμηλό σημείο τήξεως και οι εξαιρετικές ηλεκτρικές ιδιότητες τους έχουν οδηγήσει στην ολοένα και πιο ευρεία εφαρμογή τους. Ο σκοπός της παρούσας διατριβής είναι η μελέτη του εγκλωβισμού Ιονικών Υγρών σε ζεόλιθο και ο χαρακτηρισμός των παραγόμενων σύνθετων υλικών. Στο πρώτο μέρος της παρούσα διατριβής συνετέθησαν δύο διαφορετικοί ζεόλιθοι και πιο συγκεκριμένα NaY-FAU και BEA με τρείς διαφορετικές αναλογίες Si/Al (250, 50 και 25). Οι παραγόμενοι ζεόλιθοι χαρακτηρίστηκαν με Φασματοσκοπία Περίθλασης Ακτίνων-Χ (XRD), Ηλεκτρονική Μικροσκοπία Σάρωσης (SEM) και φυσιορόφηση Ν2. Στο δεύτερο μέρος της παρούσας διατριβής έγινε μελέτη του εγκλωβισμού ΙΥ σε ζεόλιθο. Πιο συγκεκριμένα μελετήθηκε ο εγκλωβισμός του 1-Η-3-μεθυλιμιδαζολο τριφθορομεθανοσουλφόνυλο ιμιδίου στο ζεόλιθο NaY-FAU. Tα προκύπτοντα σύνθετα υλικά ΙΥ/Ζ τόσο ως προς τις φυσικοχημικές αλλά και ως προς τις ηλεκτροχημικές τους ιδιότητες. Πιο συγκεκριμένα, μελετήθηκαν 2 διαφορετικές μέθοδοι εγκλωβισμού του ΙΥ στο ζεόλιθο NaY-FAU: απευθείας προσθήκη του ΙΥ στον απαερωμένο ζεόλιθο (Μέθοδος 1) και με διάλυση αρχικά του ΙΥ σε MeOH και προσθήκη του ζεόλιθου στο διάλυμα (Μέθοδος 2) και μελετήθηκε η επίδραση της αρχική αναλογία ΙΥ/Ζ και της επίδρασης της διάρκειας της εκχύλισης Soxhlet στη ποσότητα του ΙΥ που παραμένει εγκλωβισμένο και στη δομή του τελικού προϊόντος. Τέλος τα προκύπτοντα συστήματα ΙΥ/Ζ χαρακτηρίστηκαν ως προς την ιοντική τους αγωγιμότητα με Φασματοσκοπίa Σύνθετης Αντίστασης (Α. C. Impedance Spectroscopy). / Zeolites are microporous crystalline compounds that are cosntituted by SiO4 and AlO4 tetrahedra thus forming crystalline structures in one, two or three dimensions. Due to their unique physicochemical properties zeolites are widely used in industrial and laboratory applications. On the other hand, Ionic Liquids are liquids that are liquids at room temperature. Their negligible vapour pressure, the low melting point and their unique electrochemical properties have caused their extensive use in different applications. The scope of this thesis is to study the encapsulation of Ionic Liquids into zeolite structure and the characterization of the obtained composite materials. The first part presents the synthesis and characterization of two different zeolites: NaY-FAU and BEA with three different Si/Al ratio (250, 50 and 25). The obtained zeolites were characterized using X-Ray Diffraction Spectroscopy, Scanning Electron Microscopy, N2 physisorption and Thermogravimetric Analysis. In the second part, the encapsulation of 1-H-3-methylimidazolium bis(trifluoromethane sulfonyl) imide into NaY-FAU was studied. The obtained composite materials were characterized in both physicochemical and electrochemical terms. Thus, two different encapsulation methods were tested: the first on with direct addition of the ionic liquid to the zeolite (Method 1) or by preparation of a Ionic Liquid/Methanol solution and addition of the zeolite. The initial weight ratio and the duration of Soxhlet extraction influence on the properties of the final composite material were studied. Finally, the electrochemical properties of the obtained composite materials were evaluated using A. C. Impedance Spectroscopy measurements.

Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第13840号 / 工博第2944号 / 新制||工||1435(附属図書館) / 26056 / UT51-2008-C756 / 京都大学大学院工学研究科分子工学専攻 / (主査)教授 榊 茂好, 教授 川﨑 昌博, 教授 田中 庸裕 / 学位規則第4条第1項該当