Biodiesel is a renewable and biodegradable alternative green fuel for petroleum-based diesel. The major obstacle for the production of biodiesel at an industrial scale is the high production cost, which is related to the relative high price of the conventional ???1st generation feedstocks??? (refined vegetable oils) used. This problem can be addressed by using low cost feedstocks such as waste oils and fats. However, these feedstocks contain high amounts of free fatty acids (FFA) which cannot be used for the production of biodiesel using a traditional homogeneous alkali-catalyzed transesterification process. Furthermore, there is a great need to develop a green process which can be used for multiple feedstocks. This shows the universal ability of the process to be adopted as per availability of local feedstock. In this study, a single-step second generation heterogeneous-catalyzed process is developed to produce biodiesel from multi-feedstocks. Due to an increase in the commercial use of biodiesel and biodiesel blends, both ASTM D6751 and EN 14214 include the acid number (AN) as an important quality parameter. Currently, ASTM D974 and D664 analytical methods for acid number analysis of biodiesel are time consuming, expensive, and environmentally not friendly. Therefore, ASTM D974 has been modified and a green analytical method has been developed. This extensive study has demonstrated that this new method is a reliable method for the determination of AN and could be used for establishing the specifications of AN for biodiesel and biodiesel blends ranging from B1 to B20 in quality standards. The ASTM reference standard method D664, has major problems such as the use of excess toxic solvents, large sample size, mediocre reproducibility, tedious process for cleaning electrodes, and relatively long analysis time. Therefore, a new proposed method based on green chemistry approaches, has been developed to determine the acid number of biodiesel and biodiesel blends using small sample size and reduced toxic titration solvent. This proposed green analytical method could be used for the determination of AN of biodiesel and biodiesel blends in R&D as well as industrial quality control laboratories as a simple, time-efficient, cost effective and environmentally friendly method.

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Thesis (Master)--İzmir Institute of Technology, İzmir, 2006. / Keywords:Suzuki reactions, palladium, NaYzeolite, heterogeneous catalyst, C-C coupling. Includes bibliographical references (leaves. 71-81).

Thesis (MScIng)--University of Stellenbosch, 2007. / Bibliography. Also available via the Internet.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1984. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 500-516).

This thesis is based on experiments applying synchrotron based X-ray Absorption Spectroscopy(XAS) and Resonant Inelastic X-ray Scattering (RIXS) in the soft X-ray region to energy related systems. The main work of this thesis has been to develop a reaction cell that allowed for in situ XAS and RIXS investigations of the partial epoxidation of ethylene over a Ag catalyst at 1 atm and up to 250C. The developed in situ cell can be used in two sample modes: 1) the Ag catalyst is deposited directly onto the vacuum separating membrane with the reaction gases flowing beneath it or 2) a slightly compressed Ag powder sample is at a distance to the vacuum membrane with the reaction gases flowing between the Ag powder sample and the membrane.Both sample modes offers the total florescence yield, TFY, and the total electron yield, TEY, to be recorded simultaneously. By means of the developed in situ cell a number of oxygen species, residing in/on the Ag surface or in the Ag bulk, have been detected. We claim to detect adsorbed O2 under epoxidation conditions, as well as Ag–O–H groups. We are also able to monitor changes of the absorbed oxygen as we change the composition of the reaction gas feed. The first charging cycle of Li-ion batteries have been investigate by ex situ measurements on the cathode Li2-xMnSiO4 and the anode composite LixNi0:5TiOPO4/C . The initial crystalline material becomes amorphous due to lithiation during the first first charging. We find that the redox behaviors of these two states are significantly different. Sulfidation of natural copper oxides are is found to be strongly promoted when it is grown on the host metal by a disproportionation.

This thesis concerns the preparation and use of diaryliodonium salts. In Project I various unsymmetrical diaryliodonium salts were reacted with three different nucleophiles in order to study the chemoselectivity of the reactions of the salts. The main focus of this project was to gain a deeper understanding of the underlying factors that affect the chemoselectivity in transition metal-free arylation reactions. They were found to be very nucleophile-dependent. Some nucleophiles were very sensitive to electronic effects, whereas others were sensitive to steric factors. Ultimately, some arenes are never transferred. A very interesting scrambling reaction was also observed under the reaction conditions, where unsymmetrical diaryliodonium salts form symmetrical salts in situ. Project II details the preparation of N-heteroaryliodonium salts via a one-pot procedure. The salts were designed so that the N-heteroaryl moiety was selectively transferred in applications both with and without transition metals. The chemoselectivity was demonstrated by selective transfer of the pyridyl group onto two different nucleophiles. The third project in the thesis discusses the synthesis of alkynyl(aryl)iodonium salts and alkynylbenziodoxolones from arylsilanes. This protocol could potentially be a very useful complement to the existing procedures, in which boronic acids are used. The last part of the thesis (Project IV) describes a C-2 selective arylation of indoles where diaryliodonium salts were used in combination with hetero-geneous palladium catalysis. This transformation was performed in water at ambient temperature to 50 °C, and tolerated variations of both the indole and the diaryliodonium salt. Importantly, several N-H indoles could be arylated. The MCF-supported Pd-catalyst showed very little leaching and it was demonstrated that the main part of the reaction occurred via heterogeneous catalysis. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Accepted.</p>

The wettability of materials is important in many natural and industrial processes. In this thesis, the wettability of chemically heterogeneous surfaces was investigated with respect to the size, shape and orientation of individual defects. Heterogeneous surfaces were structured by photolithography, using self-assembled monolayers (SAMs) of diverse functionality and, thus, wettability. In order to maximise any possible departure from theory, the wettability of the high-and low-energy regions of these heterogenous surfaces was chosen to differ substantially. The purity of the defects was optimized by studying the SAM formation and the patterning processes, whilst the influence of roughness was minimized. The focus of this work is therefore on chemical heterogeneity. The Wilhelmy plate method was employed to ascertain the wetting behaviour of individual high- and low-energy defects. Simultaneous measurement of the capillary force and the plate position allowed full characterization of the wettability at the defect boundaries. In addition, integration of the Wilhelmy trace enabled the work associated with advancing or receding a liquid over these defects to be quantified. / The defect boundary orientation was of critical importance to the wetting behaviour. Wetting boundaries perpendicular to the liquid front did not result in any deviation from theoretical predictions. Wetting boundaries that were arranged parallel to the liquid front, however, caused contact line pinning which, in turn, caused contact angle hysteresis. Therefore these boundaries are directly responsible for the departure from wetting theory for heterogeneous surfaces (i.e. the Cassie Equation). These observations are consistent with earlier studies of wetting hysteresis by Johnson and Dettre (1964) and Neumann and Good (1972). Extending their work, this thesis examined the extent of wetting hysteresis at individual rectangular defects with respect to the defect dimensions. The nature of wetting hysteresis was studied quantitatively and, as a result, a simple model for hysteresis was proposed. This model predicts that, for a high-energy defect, the work associated with an advancing liquid will always be less than the theoretical value due to capillary rise within the effect. However, the work associated with a receding liquid will be equal to the theoretical prediction (the opposite is true for low-energy defects). The proposed model was validated for two different liquids (water and ethylene glycol) rectangular and circular defects of macroscopic dimensions. For these surfaces, the empirical data and the proposed model showed excellent agreement for both high- and low-energy defects. This agreement is strong evidence that high- and low-energy defects induce distinctly different wetting behaviour on heterogeneous surfaces. / The proposed model for hysteresis was qualitatively applied to heterogeneous surfaces containing micro- and nanoscopic defects. For micropatterns of high- and low-energy defects, of identical composition, the wettability was entirely different. High-energy defects induced a deviation from theory for only the advancing contact angles, whilst low-energy defects only influenced the receding angles. These observations were qualitatively consistent with the outcomes predicted by the proposed model for hysteresis. For nanoscopic defects, however, the advancing contact angles were consistent with Cassie's law within reasonable error. The derivation of Cassie's equation assumes that there is no capillary rise within the chemical defects. The capillary rise within a nanoscopic defect must be extremely small, according to extrapolation of measurements performed on macro and microscopic defects. Therefore, consistency between the wettability of nanoscopic defects and Cassie equation predictions might be expected. The hysteresis mechanism outlined within this thesis can be quantitatively applied to macroscopic defects, whereas its application to micro and nanoscopic defects is qualitative. / Finally, several applications of this fundamental research, which are directly related to real systems, have been outlined. These include mineral flotation, oil recovery, liquid movement, directed crystallization, Secondary Ion Mass Spectrometry for flotation analysis and patterning of inorganic surfaces. / Thesis (PhDApSc(MineralsandMaterials))--University of South Australia, 2004.

Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.

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