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.

In recent years, ionic liquids have emerged as one of the most promising alternatives to traditional volatile organic solvents when it comes to catalytic reactions. Stable metal nanoparticles suspended in ionic liquids, are catalytic systems that mimic aspects of nanoparticles on solid supports, as well as traditional metal-ligand complexes used in organometallic catalysis. While alkylimidazolium ionic liquids, with or without appended functionalities, have been earmarked as the media of choice for the dispersal of nanoparticles, the tetraalkylphosphonium family of ionic liquids has largely been overlooked, despite their facile synthesis, commercial availability, chemical resemblance to surfactants traditionally used for nanoparticle stabilization, stability under basic conditions, and wide thermal as well as electrochemical windows. It is only recently that a number of research groups have given this family of novel alternative solvents the recognition it deserves, and used metal NPs dispersed in these ILs as catalysts in reactions such as hydrogenations, oxidations, C-C cross-couplings, hydrodeoxygenations, aminations, etc. This thesis investigates the synthesis, characterization, and catalytic applications of transition metal nanoparticles in tetraalkylphosphonium ionic liquids. The ionic liquids described in this thesis functioned as the reaction media as well as intrinsic nanoparticle stabilizers during the course of the catalytic processes. Metallic nanoparticles synthesized in these ionic liquids proved to be stable, efficient and recyclable catalytic systems for reactions of industrial significance, such as hydrodeoxygenations, hydrogenations, and oxidations. It was demonstrated that stability and catalytic activity of these systems were profoundly dependent on the properties of the ionic liquids, such as the nature of the alkyl chains attached to the phosphonium cation, and the coordination ability of the anion. Since heat-induced nanoparticle sintering was a problem, a procedure was devised to redisperse the aggregated and/or sintered nanoparticles so as to restore their initial sizes and catalytic activities. The presence of halides as counter-ions in tetraalkylphosphonium ionic liquids was seen to facilitate the oxidative degradation of agglomerated metal nanoparticles, which was a key step in our redispersion protocol. It was demonstrated that this redispersion protocol, when applied to heat-sintered nanoparticles, produces nanostructures that resemble the freshly made nanoparticles not only in size but also in catalytic activities. The presence of by-products from the borohydride reduction step used to generate the nanoparticles in the ionic liquids actually facilitated multistep reactions such as hydrodeoxygenation of phenol, where a Lewis Acid was necessary for a dehydration step. Finally, an attempt was made to utilize nanoparticles of an earth-abundant metal (iron) as a hydrogenation catalyst in a variety of alternative solvents (including tetraalkylphosphonium ionic liquids) in order to enhance the “green”ness of the catalyst systems. X-ray absorption spectroscopy (XAS) of the iron- nanoparticles/ionic liquid systems at the Canadian Light Source revealed significant details about the chemical interaction between iron and the ionic liquid matrices, which added to our understanding of this neoteric family of catalysts.

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.

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.

abstract: Structural details of phosphonic acid functionalized nanomaterials and protic ionic liquids (PILs) were characterized using nuclear magnetic resonance (NMR) spectroscopy. It is well known that ligands play a critical role in the synthesis and properties of nanomaterials. Therefore, elucidating the details of ligand-surface and ligand-ligand interactions is crucial to understanding nanomaterial systems more completely. In an effort to further the understanding of ligand-surface interactions, a combination of multi-nuclear (1H, 29Si, 31P) and multi-dimensional solid-state NMR techniques were utilized to characterize the phosphonic acid functionalization of fumed silica nanoparticles using methyl phosphonic acid (MPA) and phenyl phosphonic acid (PPA). Quantitative 31P MAS solid-state NMR measurements indicate that ligands favor a monodentate binding mode. Furthermore, 1H-1H single quantum-double quantum (SQ-DQ) back-to-back (BABA) 2D NMR spectra of silica functionalized with MPA and PPA indicate that the MPA and PPA are within 4.2±0.2 Å on the surface of the nanomaterial. The ligand capping of phosphonic acid (PA) functionalized CdSe/ZnS core-shell quantum dots (QDs) was investigated with a combination of ligand exchange, solution and solid-state 31P NMR spectroscopy. In order to quantify the ligand populations on the surface of the QDs, ligand exchange facilitated by PPA resulted in the displacement of the PAs, and allowed for quantification of the free ligands using 31P liquid state NMR. In addition to characterizing nanomaterials, the ionicity and transport properties of a series of diethylmethylamine (DEMA) based protic ionic liquids (PILs) were characterized, principally utilizing NMR. Gas phase proton affinity was shown to be a better predictor for the extent of proton transfer, and in turn the ionicity of the PIL, than using ∆pKa. Furthermore, pulsed field gradient (PFG) NMR was used to determine that the exchangeable proton diffuses with the cation or the anion based on the strength of the acid used to generate the PILs. / Dissertation/Thesis / Doctoral Dissertation Chemistry 2015

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. / Applied Science, Faculty of / Materials Engineering, Department of / Graduate

This research explored the amination reaction of 1,3-bis-chloromethyl-tetramethyl-disiloxane in two different pathways. First, will discuss the synthesis of a new bipodal amino siloxane ligand which was achieved by the reaction of bis-chloromethyl-tetramethyl-disiloxane with t-BuNH3 in the presence of n-BuLi. The new ligand, of t-Butyl-[3-(t-butylamino-methyl)-1,1,3,3-tetramethyl disiloxanylmethyl]-amine (L1), is a model ligand designed to simulate the SOMC model of silica support and bipodal amido ligand that has been presented by the Basset group. Hence, developing this type of siloxane ligand and their complexes will be valuable in the synthesis of new homogenous catalyst, studying the reactivity and attempt to connect them with the SOMC examples. For this, the reaction of L1 with several Lewis acids and afforded several uncommon dimer and cluster complexes in the solid state. The second part of this research found that heating of bis-chloromethyl-tetramethyl-disiloxane with a 4-6 equivalent of amine, affording 4-N-Alkyl-tetramethyl- oxazadisilinane as six heterocycle ring by using a new simple and neat method. Using six different amine functional groups afforded six new oxazadisilinane compounds with different alkyls substituted. Each oxazadisilinane compound was utilized and reacted with four different acids, affording a series of twenty-one examples of new siloxane protic ionic liquids (Si-PILs). Also, the reaction of the cation with methyl iodide provided two examples of siloxane aprotic ionic liquids (Si-AILs). The new family of Si-ILs were well characterized by using NMR, mass, melting point, elemental analysis and thermal gravimetric analyses. Additionally, twelve crystals were suitable for X-ray diffraction as Si-PILs and one for Si-AILs. By studying their chemical and physical properties, a good library of the new Si-ILs has been built. Finally, one group of the new Si-PILs was used for butyl acetate esterification. The 5-X group of new Si-PILs salt was tested for esterification of butanol with acetic acid by thermal heat and under microwave irradiation. The salt 5-BF4- showed a good result in both systems with easy separation from the reaction mixture and recyclability discriminates the 5-BF4- as a good catalyst for the esterification reaction.

No description available.

Various innovative separation methods in chromatography have been proposed. The interaction of the 4-t-butylphenyl group with b-cyclodextrin is well-known; compounds tagged with the 4-t-butylphenyl group are separated from untagged compounds using b-cyclodextrin column. In this study, increasing the chain length of tagged molecules does not increase the retention time but depends on other functional groups present, while increasing the number of tags in a molecule increases retention time. The t-butyl group was also compared to adamantyl and lithocholic acid tags. In-house b-cyclodextrin columns were synthesized to observe the effect of the linkage of the cyclodextrin molecule to the support. Furthermore, tagged products could be separated from the starting materials using in-house columns employing flash b-cyclodextrin. Supported room temperature ionic liquids (SILs/MSILs) were explored for the extraction of polyunsaturated triacylglycerols (PUTAGs).Various room temperature ionic liquids (RTILs) with silver salts were tested for extraction effectiveness.The most hydrophobic RTIL [Hmim][PF6] in this study, with dissolved AgBF4 proved to be the best combination for effective extraction. RTILs supported on silica gel and mesoporous SBA-15 reacted with silver salts (psorbents) were synthesized and characterized. The later support revealed a conserved mesopore structure by SEM, TEM, SAXS and N2 isotherms. Trilinolenin (tri-18:3) quantification was explored by conversion to polyunsaturated fatty acid alcohols and methyl esters, Proton NMR spectroscopy and by non-aqueous reverse phase (NARP)-HPLC with evaporative light scattering detector (ELSD). Tri-18:3 and its free fatty acid (FFA-18:3) were extracted selectively and quantified using a two-step methodology. The extraction of a-tocopherol with RTILS modified with organic anions was also successfully demonstrated. Finally, studies of chiral stationary phases with on-resin cyclic oligoprolines were demonstrated. Cross linking of linear oligoprolines was shown to disrupt the poly-proline helix (II) thus leading to lower number of analytes resolved. On-resin cyclic oligoproline synthesis was successful for penta- and tetraproline but failed for the triproline. PyBOP/HOBt/DIPEA was employed for effective cyclization. The on-resin cyclic oligoproline CSP showed a lower number of resolved analytes, implying the importance of the poly-proline helix for chiral selectivity. The innovative separations in this study serve as starting points for developing mature separation methods.

No description available.