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Silica-based monolithic HPLC columns contain a novel chromatographic support in which the traditional particulate packing has been replaced with a single, continuous network (monolith) of porous silica. The main advantage of such a network is decreased backpressure due to macropores (2 μM) throughout the network. This allows high flow rates, and hence fast analyses that are unattainable with traditional particulate columns. The Chromolith SpeedROD™ (EM Science, Gibbstown NJ) is a commercially available silica-based monolithic column. This work investigated the chromatographic properties of the 50x4.60 mm (ODS) SpeedROD™. Data fit to the van Deemter equation (mean square error=0.834) indicated that the van Deemter model was valid for monolithic columns. An effective particle size of 4 μM for the SpeedROD™ column was assigned by comparing the minimum of van Deemter curves with a series of particulate columns having various particle diameters. Separation Impedance (E), an empirically derived measure of column performance, was calculated as an alternate method of evaluating column efficiency. Data collected using this model confirmed monolithic columns behaves as a (more efficient) 3 μM column. A series of experiments were designed to compare the effects of mobile phase strength and mobile phase viscosity between the SpeedROD™ column and a particulate column. The results indicated both solvent strength and viscosity have effects on the monolithic column at the optimum linear velocity. A fast (90 s) HPLC method was developed using the SpeedROD™ column and a seven-component test mixture with a large range of hydrophobicities. The precision for both retention time and peak area was measured at high linear velocities (8 mL/min) and the percent relative standard deviation (RSD) calculated. Column to column reproducibility (n=6) was measured. The overall percent RSD ranged from 0.25% to 4.56% for retention time and from 1.08% to 6.77% for peak area. Run to run reproducibility (n=15) was measured for all six columns. Averages ranged for retention time from 0.89% to 5.09% RSD and for peak area from 4.65% to 6.18% RSD. Applications for the SpeedROD™ column with various sample types were developed and discussed. These methods demonstrated the effectiveness of the SpeedROD™ at fast flow rates. / Ph. D.

Although the transesterification reaction of triglycerides with alcohols is well known and practiced on a commercial scale (using acid or alkaline catalysts), there is plenty of scope to improve this process. One approach involves the use of heterogeneous catalysts that could be retained in a fixed bed, and this would enable a continuous process to be developed. With this aim in mind, zinc proline (Zn(C5H8NO2)2) was used as a catalyst, which was coated onto a cordierite monolith support (62 cells/cm2). Two different coating methods were explored, and SEM images of the surface revealed interesting crystal structures on the surface of the cordierite. Experiments were then performed in a batch reactor (120 ml) to assess the activity of the catalyst (molar ratio methanol:rapeseed oil = 12:1, T = 195ºC and P = 20 bar, 2 h duration). Although high conversions could be achieved, the catalyst was found to lose activity with time, and even the cordierite support was also found to be catalytically active. These aspects were explored further, in a continuous flow reactor, which had an i.d. = 6.2 mm, and multiple heated sections (500 mm each) into which pieces (10 mm long) of catalyst coated monoliths were inserted. Experiments were performed with packed lengths of 200 and 400 mm, and with liquid flows ranging from 0.1 to 2.9 ml min-1. Although it was shown that high conversions can be achieved over extended run-times (e.g. 100 to 200 min), it was clear that the catalyst was losing its activity. Measurements also showed, that during the course of an experiment, Zn was leaching, and this clearly contributed to catalyst deactivation Despite the loss in activity of the zinc proline catalyst, the reaction system developed in this thesis was shown to work well, and that it could be used to evaluate the performance of catalytically coated sections of monolith. To demonstrate the use of this system, a few scoping studies were also performed using SrO as a catalyst, which was coated onto the cordierite monolith.

The research presented in this work explores the application of microfluidics to the field of proteomics through the design of a multi-channel microfluidic platform and the investigation of individual components of the system. The design of this microfluidic device allows the integration of several protein sample preparation steps for automated electrospray ionization mass spectrometric (ESI-MS) analysis, including protein separation, fractionation and collection, preconcentration and cleanup, and protein digestion. In order for the multi-channel system to function properly, I first evaluated each individual component of the device. Several areas were explored: (i) optimization of polymer monolith for solid-phase extraction (SPE) preconcentration; (ii) investigation of cationic coatings for microchannel surface modification to facilitate positive electrospray of peptides and proteins for chip-MS coupling; (iii) combination of the hydrophobic monolith and the PolyE-323 coating in a single channel device for on-chip SPE and on-bed tryptic digestion with on-line coupling to ESI-MS. Multiplexed microfluidic devices for protein analysis, which integrate a series of microfluidic features, were then designed, built and tested. The multiplexed microfluidic architecture employed a separation channel, a fractionator, an array of microchambers to accommodate monolithic polymer for SPE preconcentration, and an elution channel for the detection of eluted sample using fluorescence detector or mass spectrometer. The performance of the multiplexed devices for integration of multiple analytical steps was explored with sequential fractionation, collection, and elution of fluorescent sample, evaluating the ability to trap and release individual fractions without cross-contamination. Thorough analysis of each of the individual components on the multiplexed microfluidic platform provides valuable insights into the design of such systems, which brings us closer to our final goal of a proteomic processing microchip.

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In this thesis, the development and use of a transient heterogeneous 2D model for monolithic catalytic converter is presented. Study on the cold flow hydrodynamics, temperature effect and CO conversion and light off behaviour of different models is developed. Different models are studied based on different parameters such as monolith brick CPSI configuration, size of the converter, inlet cone sizing and inlet velocity of the converter. The results for both steady state and transient modes are presented in detail. It is shown that monolith brick CPSI has a significant effect on pressure drop and light-off behaviour of the converter. Also, converter size has a major effect on the performance of a converter. Inlet cone sizing showed to have a significant effect on the hydrodynamics of the converter but it did not have a major effect on light-off behaviour of the converter. / Chemical Engineering

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京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21795号 / 工博第4612号 / 新制||工||1718(附属図書館) / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 辻井 敬亘, 教授 山子 茂, 教授 渡辺 宏 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

L’objectif de la thèse est la synthèse et l’optimisation des supports monolithiques et l’évaluation de leur efficacité en cuisson kraft et lors du recyclage (essai des catalyseurs dans un réacteur de capacité 5 kg). Lors de cette thèse, nous avons montré que l’utilisation des monolithes styréniques anthraquinoniques à base de diméthacrylate de diéthylèneglycol et de divinylbenzène en cuisson permettent d’économiser de l’alcali actif consommé et d’augmenter le rendement en pâtes à des indices kappa faibles. Les monolithes à base de diméthacrylate de diéthylèneglycol sont plus efficaces en cuisson que ceux à base de divinylbenzène, avec des gains comparables à l’effet de l’anthraquinone commerciale et gardent leur activité catalytique lors du recyclage. / The objective of the thesis is the synthesis and optimization of monolithic supports and the evaluation of their efficiency in the kraft process and after recycling (test of catalysts inside a 5 kg capacity reactor). In this work, we showed that the presence of monoliths styrene-anthraquinone-diethyleneglycoldimethacrylate or styrene-anthraquionone-divinylbenzene in the kraft process could save up the active alkali consumed and could increase the yield in pulp at low indice kappa. The monoliths styrene-anthraquionone-diethyleneglycoldimethacrylate are more efficiently in cooking process than those containing divinylbenzene. Their performance is closed of that of the commercial anthraquinone and this catalytic activity persists even after recycling.

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