Darmstadt, Techn. Universiẗat, Diss., 2001. / Dateiformat: tar.gz, Dateien im PDF-Format.

Thesis(B.Sc.)--University of Adelaide, dept. of Organic Chemistry, 1966. / Typescript.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1957. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 85-86).

Au cours de ce projet, il a été démontré qu’il était possible d’appliquer un procédé utilisant comme solvant du 2-MeTHF ainsi que du Nickel de Raney comme catalyseur afin de valoriser par hydroliquéfaction différentes formes de biomasse résiduelles. Dans un premier temps, ce procédé, résumé dans un premier article, s’est avéré efficace pour trois différentes sources de carbone : des déchets ménagers, des boues de station d’épuration et des microalgues. Malgré que la réaction soit affectée par le type de solvant ainsi que la température d’opération, il a été démontré que le 2-MeTHF (un solvant vert) pouvait remplacer la tétraline (un solvant de source fossile) pour l’hydroliquéfaction de ces différentes sources de carbone. L’hydroliquéfaction de ces biomasses a permis la production d’huiles à haute valeur énergétique, se comparant à celle d’un biocarburant. Dans un deuxième article, le même procédé (utilisant le même solvant et catalyseur) a été optimisé pour la liquéfaction d’une fraction de la biomasse lignocellulosique soit la fraction oligomérique issue de la dépolymérisation alcaline de la lignine. Une analyse complète de la liquéfaction d’oligomères d’induline, lignine provenant des liqueurs issus de l’industrie papetière, a révélé la production de trois fractions : une fraction gazeuse, une liquide (soluble dans l’hexane) et une solide (insoluble dans l’hexane). L’analyse élémentaire de la fraction solide a révélé une baisse massique de 15,4% d’oxygène et une augmentation massique de 1,4% d’hydrogène par rapport aux oligomères utilisés comme réactifs. Une chaleur massique (HHV) de 34,0 kJ/g a été mesurée par bombe calorimétrique pour la fraction solide. L’analyse par chromatographie en phase gazeuse couplée à un spectromètre de masse (GC-MS) de la fraction liquide a permis d’identifier la présence de nombreux monomères tel le 2-methoxy-phénol, de 4-éthylgaïacol et le crésol. Une HHV de 34,2 kJ/g a été mesurée par bombe calorimétrique de la fraction liquide. La fraction gazeuse était principalement constituée de méthane et de CO[indice inférieur 2].

<p>The aim of this project is to investigate the possibilities of minimizing the sulphur content in Kraft lignin. Kraft lignin contains about 1.5 to 3% sulphur. The sulphur is believed to be present in lignin as inorganic sulphur, as elemental sulphur, as adsorbed polysulphide and/or as organically bound sulphur. For the determination of these different types of sulphur components, different approaches and methods were used. For the determination of inorganic sulphur, lignin was washed with water at pH 6 and pH 2 and the wash waters were analysed with ion chromatography (IC). For the determination of total sulphur content in the lignin, two methods were used; Schöniger combustion followed by ion chromatography (IC) and wet digestion followed by inductively coupled plasma (ICP). The elemental sulphur content in water-extracted lignin was determined after n-pentane extraction. ICP analysis was performed on the washed lignin.</p><p>Calcium present in the lignin may bind polysulphides and thus be a source of the observed sulphur. The lignin was thus ion-exchanged to remove any calcium. To further investigate how the sulphur content in lignin can be decreased, two different types of reactions were performed on lignin; oxidation and reduction. The oxidation reactions were made in sodium hydroxide with oxygen at different temperatures and time on both original and water-extracted lignin. The reduction reactions were made on water-extracted lignin with Raney nickel in three different solvent systems: methanol: water, acetone: water and sodium hydroxide.</p><p> </p><p>The original lignin contained 2.6% sulphur as determined by ICP. Washing lowered the content to 1.85% sulphur. By n-pentane extraction the elemental sulphur was lowered to a level of 1.82% sulphur, which was considered to be organically bound sulphur. Neither the ion exchange nor the oxidation lowered the sulphur content significantly.</p><p> </p><p>The reduction reactions successfully the organically bound sulphur from 1.82% to a level of 0.54%.</p><p> </p><p>The relative distribution of the sulphur content in the studied softwood lignin was as follows: about 29% as inorganic sulphur, about 1% as elemental sulphur and approximately 70% as organically bound sulphur, of which 49% could be removed by Raney nickel.</p>

The aim of this project is to investigate the possibilities of minimizing the sulphur content in Kraft lignin. Kraft lignin contains about 1.5 to 3% sulphur. The sulphur is believed to be present in lignin as inorganic sulphur, as elemental sulphur, as adsorbed polysulphide and/or as organically bound sulphur. For the determination of these different types of sulphur components, different approaches and methods were used. For the determination of inorganic sulphur, lignin was washed with water at pH 6 and pH 2 and the wash waters were analysed with ion chromatography (IC). For the determination of total sulphur content in the lignin, two methods were used; Schöniger combustion followed by ion chromatography (IC) and wet digestion followed by inductively coupled plasma (ICP). The elemental sulphur content in water-extracted lignin was determined after n-pentane extraction. ICP analysis was performed on the washed lignin. Calcium present in the lignin may bind polysulphides and thus be a source of the observed sulphur. The lignin was thus ion-exchanged to remove any calcium. To further investigate how the sulphur content in lignin can be decreased, two different types of reactions were performed on lignin; oxidation and reduction. The oxidation reactions were made in sodium hydroxide with oxygen at different temperatures and time on both original and water-extracted lignin. The reduction reactions were made on water-extracted lignin with Raney nickel in three different solvent systems: methanol: water, acetone: water and sodium hydroxide.   The original lignin contained 2.6% sulphur as determined by ICP. Washing lowered the content to 1.85% sulphur. By n-pentane extraction the elemental sulphur was lowered to a level of 1.82% sulphur, which was considered to be organically bound sulphur. Neither the ion exchange nor the oxidation lowered the sulphur content significantly.   The reduction reactions successfully the organically bound sulphur from 1.82% to a level of 0.54%.   The relative distribution of the sulphur content in the studied softwood lignin was as follows: about 29% as inorganic sulphur, about 1% as elemental sulphur and approximately 70% as organically bound sulphur, of which 49% could be removed by Raney nickel.

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