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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Densification of selected agricultural crop residues as feedstock for the biofuel industry

Adapa, Phani Kumar 07 September 2011 (has links)
The two main sources of biomass for energy generation are purpose-grown energy crops and waste materials. Energy crops, such as Miscanthus and short rotation woody crops (coppice), are cultivated mainly for energy purposes and are associated with the food vs. fuels debate, which is concerned with whether land should be used for fuel rather than food production. The use of residues from agriculture, such as barley, canola, oat and wheat straw, for energy generation circumvents the food vs. fuel dilemma and adds value to existing crops. In fact, these residues represent an abundant, inexpensive and readily available source of renewable lignocellulosic biomass. In order to reduce industrys operational cost as well as to meet the requirement of raw material for biofuel production, biomass must be processed and handled in an efficient manner. Due to its high moisture content, irregular shape and size, and low bulk density, biomass is very difficult to handle, transport, store, and utilize in its original form. Densification of biomass into durable compacts is an effective solution to these problems and it can reduce material waste. Upon densification, many agricultural biomass materials, especially those from straw and stover, result in a poorly formed pellets or compacts that are more often dusty, difficult to handle and costly to manufacture. This is caused by lack of complete understanding on the natural binding characteristics of the components that make up biomass. An integrated approach to postharvest processing (chopping, grinding and steam explosion), and feasibility study on lab-scale and pilot scale densification of non-treated and steam exploded barley, canola, oat and wheat straw was successfully established to develop baseline data and correlations, that assisted in performing overall specific energy analysis. A new procedure was developed to rapidly characterize the lignocellulosic composition of agricultural biomass using the Fourier Transform Infrared (FTIR) spectroscopy. In addition, baseline knowledge was created to determine the physical and frictional properties of non-treated and steam exploded agricultural biomass grinds. Particle size reduction of agricultural biomass was performed to increase the total surface area, pore size of the material and the number of contact points for inter-particle bonding in the compaction process. Predictive regression equations having higher R2 values were developed that could be used by biorefineries to perform economic feasibility of establishing a processing plant. Specific energy required by a hammer mill to grind non-treated and steam exploded barley, canola, oat and wheat straw showed a negative power correlation with hammer mill screen sizes. Rapid and cost effective quantification of lignocellulosic components (cellulose, hemicelluloses and lignin) of agricultural biomass (barley, canola, oat and wheat) is essential to determine the effect of various pre-treatments (such as steam explosion) on biomass used as feedstock for the biofuel industry. A novel procedure to quantitatively predict lignocellulosic components of non-treated and steam exploded barley, canola, oat and wheat straw was developed using Fourier Transformed Infrared (FTIR) spectroscopy. Regression equations having R2 values of 0.89, 0.99 and 0.98 were developed to predict the cellulose, hemicelluloses and lignin compounds of biomass, respectively. The average absolute difference in predicted and measured cellulose, hemicellulose and lignin in agricultural biomass was 7.5%, 2.5%, and 3.8%, respectively. Application of steam explosion pre-treatment on agricultural straw significantly altered the physical and frictional properties, which has direct significance on designing new and modifying existing bins, hoppers and feeders for handling and storage of straw for biofuel industry. As a result, regression equations were developed to enhance process efficiency by eliminating the need for experimental procedure while designing and manufacturing of new handling equipment. Compaction of low bulk density agricultural biomass is a critical and desirable operation for sustainable and economic availability of feedstock for the biofuel industry. A comprehensive study of the compression characteristics (density of pellet and total specific energy required for compression) of ground non-treated and steam exploded barley, canola, oat and wheat straw obtained from three hammer mill screen sizes of 6.4, 3.2 and 1.6 mm at 10% moisture content (wb) was conducted. Four preset pressures of 31.6, 63.2, 94.7 and 138.9 MPa, were applied using an Instron testing machine to compress samples in a cylindrical die. It was determined that the applied pressure (60.4%) was the most significant factor affecting pellet density followed by the application of steam explosion pre-treatment (39.4%). Similarly, the type of biomass (47.1%) is the most significant factor affecting durability followed by the application of pre-treatment (38.2%) and grind size (14.6%). Also, the applied pressure (58.3%) was the most significant factor affecting specific energy required to manufacture pellets followed by the biomass (15.3%), pre-treatment (13.3%) and grind size (13.2%), which had lower but similar effect affect on specific energy. In addition, correlations for pellet density and specific energy with applied pressure and hammer mill screen sizes having highest R2 values were developed. Higher grind sizes and lower applied pressures resulted in higher relaxations (lower pellet densities) during storage of pellets. Three compression models, namely: Jones model, Cooper-Eaton model, and Kawakita-Ludde model were considered to determine the pressure-volume and pressure-density relationship of non-treated and steam exploded straws. Kawakita-Ludde model provided the best fit to the experimental data having R2 values of 0.99 for non-treated straw and 1.00 for steam exploded biomass samples. The steam exploded straw had higher porosity than non-treated straw. In addition, the steam exploded straw was easier to compress since it had lower yield strength or failure stress values compared to non-treated straw. Pilot scale pelleting experiments were performed on non-treated, steam exploded and customized (adding steam exploded straw grinds in increments of 25% to non-treated straw) barley, canola, oat and wheat straw grinds obtained from 6.4, 3.2, 1.6 and 0.8 mm hammer mill screen sizes at 10% moisture content (wb). The pilot scale pellet mill produced pellets from ground non-treated straw at hammer mill screen sizes of 0.8 and 1.6 mm and customized samples having 25% steam exploded straw at 0.8 mm. It was observed that the pellet bulk density and particle density are positively correlated. The density and durability of agricultural straw pellets significantly increased with a decrease in hammer mill screen size from 1.6 mm to 0.8 mm. Interestingly, customization of agricultural straw by adding 25% of steam exploded straw by weight resulted in higher durability (> 80%) pellets but did not improve durability compared to non-treated straw pellets. In addition, durability of pellets was negatively correlated to pellet mill throughput and was positively correlated to specific energy consumption. Total specific energy required to form pellets increased with a decrease in hammer mill screen size from 1.6 to 0.8 mm and also the total specific energy significantly increased with customization of straw at 0.8 mm screen size. It has been determined that the net specific energy available for production of biofuel is a significant portion of original agricultural biomass energy (89-94%) for all agricultural biomass.
192

Fundamental understanding of the biochemical conversion of Buddleja davidii to fermentable sugars

Hallac, Bassem Bishara 29 March 2011 (has links)
Lignocellulosic bioethanol is currently being explored as a substitution to fossil fuels. Many lignocellulosic materials are being examined but the importance is to find those with attractive agro-energy features. Producing lignocellulosic ethanol is challenging because lignocellulosic biomass is resistant to chemical and biological degradation. To reduce biomass recalcitrance, a pretreatment stage is required. Pretreatment is considered to be the most intensive operating/operating cost component of cellulosic ethanol production. Therefore, research is heavily focused on understanding the effect of pretreatment technologies on the fundamental characteristics of lignocellulosic biomass. The first study in the thesis investigates Buddleja davidii as a potential biomass source for bioethanol production. The work focuses on the determination of ash, extractives, lignin, hemicellulose, and cellulose content in this plant, as well as detailed elucidation of the chemical structures of both lignin and cellulose by NMR spectroscopy. The study showed that B. davidii has several unique agro-energy features as well as some undesired characteristics. The second study presents research on the ethanol organosolv pretreatment (EOP) of B. davidii and its ability to produce enzymatically hydrolysable substrates. It was concluded that the removal of hemicellulose, delignification, reduction in the degree of polymerization (DP) of cellulose, and the conversion of crystalline cellulose dimorphs (Iα/Iβ) to the easily degradable para-crystalline and amorphous celluloses were the characteristics accounted for efficient enzymatic deconstruction of B. davidii after EOP. The third study provides a detailed elucidation of the chemical structure of ethanol organosolv lignin (EOL) of B. davidii by NMR spectroscopy. Such research was needed to understand the pretreatment mechanism in the context of delignification and alteration of the lignin structure. Future applications of the resulted EOL will be valuable for industrially viable bioethanol production process. EOP mainly cleaved β-O-4' interlinkages via homolysis, decreased the DP of lignin, and increased the degree of condensation of lignin. EOL had low oxygen content, molecular weight, and aliphatic OH as well as high phenolic OH, which are qualities that make it suitable for different co-product applications. The last study provides information on the anatomical characteristics of pretreated B. davidii biomass after EOP. The importance of this research was to further understand the alterations that occur to the cellular structure of the biomass which can then be correlated with its enzymatic digestibility. The results concluded that the physical distribution of lignin within the biomass matrix and the partial removal of middle lamella lignin were key factors influencing enzymatic hydrolysis.
193

Valorisation chimique de la biomasse oléagineuse d’origine béninoise : Lophira lanceolata et Carapa procera / Chemical enhancement of the oleaginous biomass from Benin : Lophira lanceolata and Carapa procera

Nonviho, Guévara 22 April 2015 (has links)
Lophira lanceolata (Ll) et Carapa procera (Cp) sont des plantes oléagineuses, peu étudiées. Au Bénin, elles sont pourtant utilisées à des fins alimentaires, cosmétiques et thérapeutiques. Cette étude vise la caractérisation de leurs graines, coques et bois. Les huiles végétales de Ll ont été obtenues par différentes méthodes dont une aqueuse traditionnelle tandis que celle de Cp l’a été par utilisation d’hexane. De façon générale, les huiles de Ll montrent un profil nutritionnel riche en acides gras polyinsaturés (>50% m/m: masse pour masse). Outre ses propriétés chimiques meilleures, celle obtenue par le procédé traditionnel est plus riche en acides gras essentiels, en composés phytostéroliques comme le lupéol et en tocols. La torréfaction et l’utilisation d’enzymes ont également permis d’évaluer l’impact de ces méthodes sur la composition chimique des graines de Ll. Quant aux graines de Carapa p., elles présentent un profil plutôt abondant en acides gras monoinsaturés, en tocotriénols (85,56% m/m) et en lanostérols (28,03%, m/m). Les tourteaux, coques et bois des deux espèces montrent une variabilité chimique en composés pariétaux (extractibles, hémicelluloses, celluloses et lignines). Une caractérisation in fine des hémicelluloses de ces parties des deux plantes a permis de montrer qu’elles sont essentiellement de type glucuronoxylanes. Les extractibles de ces plantes ont également offert une large gamme de composés à connotations industrielles et pharmaceutiques positives. Enfin, les conditions optimales de la biosorbption du bleu de méthylène sur les coques de Lophira ont également été évaluées. Cette évaluation a permis de mettre en exergue la potentielle utilisation de ces résidus agroforestiers pour rendre potables les eaux usées industrielles / The chemical composition of wild oilseeds, such as Lophira lanceolata (Ll) and Carapa procera (Cp) of Benin is mostly unknown. Yet they undergo crafted transformations for food, cosmetic and therapeutic purposes. This study aims to characterize their seeds, hulls and woods. From these crops, different oils have been extracted. One of them has been produced in rural area according to aqueous ancestral method. On the whole, oils of Ll have presented an interesting nutritional profile. They are rich in polyunsaturated fatty acids (> 50% m/m: mass for mass), especially that extracted by artisanal process. Beyond its good chemical properties, it provides essential fatty acids, phytosterols such as lupeol and more tocols compounds. Roasting and the use of enzymes have also assessed the impact of these methods on the chemical composition of LI seeds. Differently, Cp oil’s has an abundant presence of MUFA, tocotrienols (85.56% w/w) and the richest composition in lanosterol (28.03%, m/m). The seeds cakes, hulls and wood of both species showed various distributions on chemical components (extractives, hemicellulose, cellulose and lignin). The characterization of hemicelluloses from different parts of plants has shown that they are essentially glucuronoxylans type. Extractives also offered a wide range of compounds mostly appreciated for industrial and pharmaceutical purposes. The chemical composition of the shells of Lophira was rich in organic compounds such as lignin (32.13%, dry weight) so their biosorbent capacity was evaluated. They showed methylene blue good adsorption capacity in aqueous solution, which highlighted their potential use in the purification of wastewater
194

Investigation into the characteristics and possible applications of biomass gasification by-products from a downdraft gasifier system

Melapi, Aviwe January 2015 (has links)
Biomass gasification has attracted the interest of researchers because it produces zero carbon to the atmosphere. This technology does not only produce syngas but also the byproducts which can be used for various application depending on quality.The study conducted at Melani village in Alice in the Eastern Cape of South Africa was aimed at investigating the possible applications of the gasification byproducts instead of being thrown away. Pine wood was employed as the parent feedstock material for the gasifier. Biomass gasification by-products were then collected for further analysis. The studied by-products included tar(condensate), char, soot and resin. These materials were also blended to produce strong materials.The essence of the blending was to generate ideal material that is strong but light at the same time.The elemental analysis of the samples performed by CHNS analyser revealed that carbon element is in large quantities in all samples. The FTIR spectra showed almost similar results for all the studied samples, since the samples are end products of lignocellulosegasification. SEM gave the sticky images of resin as well as porous char structures. Char showed a higher heating value of 35.37MJ/Kg when compared to other by-products samples.
195

Isolation and characterisation of lignocellulose degrading bacteria from Tyume River in the Eastern Cape Province, South Africa

Tembisa, Papiyana Ayavuya January 2015 (has links)
This study focuses on the isolation and characterization of bacteria from lignocellulosic biomass obtained from the sediments of the Tyume River in Alice, Eastern Cape and to determine those bacterial isolates with good potential for modification and decomposition of lignocellulosic biomass for industrial application. Several bacterial isolates were recovered and screened for ability to degrade various lignocellulosic materials. Nine of the isolates were positive for lignocellulolytic activity. Four isolates were cellulase positive and six were xylanase positive. Moreover, one isolate (SB1) was positive for both xylanase and cellulase activities and showed the best hydrolysis zone on solid media. This isolate was then chosen as the best and identified molecularly. The 16S rDNA sequence analysis indicated that SB1 was a Bacillus cereus species. Factors affecting the cellulose and xylanase enzyme production by the organisms were studied. The organisms produced the enzymes maximally at earlier hours of incubation (12-30 hr) and optimally at acidic pH (3-5) and at moderate temperatures (35-45ºC). SB1 appears to hold promise in the decomposition of lignocellulosic wastes.
196

Modification of lignin derivatives for polymerization in water / Modifiering av lignin-derivat för polymerisering i vatten

Södergren, Adrian January 2022 (has links)
För att möjliggöra en hållbar utveckling skiftar många polymerforskares fokus just nu från att syntetisera polymerer från fossila resurser till att producera biobaserade polymerer från exempelvis träd. Av särskilt intresse är lignin, som utgör ungefär en tredjedel av allt växtmaterial men i nuläget oftast används som bränsle. Många forskare har undersökt de möjligheter som öppnas genom att bryta ner lignin och modifiera molekylerna som fås därigenom, såsom ferulsyra. Denna studie syftade till att modifiera ferulsyra till en styren-lik monomer med en karboxyl-substituent, och att testa vattenbaserad polymerisation av denna monomer.Det första steget i modifiering var dekarboxylering av ferulsyra. Detta utfördes genom upprepningar av tidigare studier där baskatalyserad dekarboxylering utfördes i polära aprotiska lösningsmedel. Efter flera försök hittades en fungerande metod, där trietylamin gav en dekarboxylering med högt utbyte efter tre timmar i dimetylformamid vid 100 °C. Att isolera produkten var också utmanande i början, men en trestegs-extraktion med H2O och Et2O som avslutades med en tvätt av saltvatten gav tillräcklig renhet. En ättiksyra-grupp adderades till fenolen med hjälp av en tvåstegsreaktion som hittades i litteraturen, men inte förrän ett dussin försök till nya metoder med kloroättiksyra gjorts utan framgång. I den fungerande metoden tillsattes en acetatgrupp med metylbromoacetat i återkokande aceton med kaliumkarbonat som bas, innan acetatet demetylerades av litiumhydroxid i en metanol/vattenblandning vid rumstemperatur.Den resulterande monomeren, 4-oxy-ättiksyra-3-methoxy-styren (OAMS), sampolymeriserades med styren, både i bulk- och emulsionspolymerisation. Bulksampolymeren hade en något högre molekylvikt och glastransitionstemperatur än homopolystyren, med en betydligt högre dispersitet. Emulsionspolymerisation var utmanande, eftersom OAMS inte är särskilt löslig i vare sig vatten eller styren, och i slutändan producerades inga tydliga resultat genom dessa försök.  Studiens huvudsakliga slutsats är att även om det är möjligt att syntetisera ren OAMS från ferulsyra, är användbarheten av denna molekyl som monomer i vattenbaserad polymerisering inte övertygande, eftersom den är så pass olöslig om inte bas tillsätts, vilket introducerar risken för hydrolys.Slutligen, även om studien ledde till få säkra slutsatser på grund av flera ofullständiga resultat, uppnåddes huvudsyftet att modifiera ferulsyra och testa polymerisation av den bildade monomeren. / To enable a sustainable development, scientific focus is shifting from synthesizing polymers from fossil-based resources to producing bio-based polymers from for example wood. Of particular interest is lignin, which makes up about a third of plant matter but is nowadays most commonly used as fuel. A great deal of research has explored the possibilities opened up by breaking down lignin and modifying its derived molecules, such as ferulic acid. This study aimed to modify ferulic acid into a styrenic monomer with an acidic substituent, and to investigate the aqueous polymerization of this monomer.The first step of modification was the decarboxylation of ferulic acid. This was attempted through recreations of previous studies where base-catalysed decarboxylation was carried out in aprotic polar solvents. After several trials, a successful procedure was found, where triethylamine gave a high-yield decarboxylation after three hours in dimethylformamide at 100 °C. Isolating the product was also initially challenging, but a three-step extraction with H2O and Et2O finished by a wash of brine gave sufficient purity.Adding an acetic acid-group to the phenol was achieved using a two-step procedure found in literature, but not before trying a dozen novel methods using chloroacetic acid without success. In the working procedure, an acetate group was added using methyl bromoacetate in refluxed acetone with potassium carbonate as base, before demethylating the acetate using lithium hydroxide in a methanol/water mix at room temperature. The resulting monomer, 4-oxy-acetic acid-3-methoxy-styrene (OAMS), was copolymerized with styrene, both in bulk and emulsion radical polymerization. The bulk copolymer displayed a slightly higher molecular weight and glass transition temperature than homopolystyrene, with a significantly higher dispersity. Emulsion polymerization was challenging, as OAMS is not very soluble in either water or styrene, and ultimately, no conclusive results were produced through this route.The study concluded that while it is possible to synthesize pure OAMS from ferulic acid, the degree of usability of this molecule as a monomer in aqueous polymerization is not certain, as it is hardly soluble without the addition of base, which introduces the risk of hydrolysis. Ultimately, although few solid conclusions could be drawn from this study due to several incomplete results, the core objective of modifying ferulic acid and testing polymerization of the resulting monomer was achieved.
197

Improving digestibility of cattle waste by thermobarical treatment

Budde, Jörn 16 April 2015 (has links)
Im Laborversuch konnte der positive Einfluss einer thermobarischen Vorbehandlung auf die Hydrolysier- und Vergärbarkeit von Rinderfestmist und Rindergülle nachgewiesen werden. Die Laborergebnisse wurden innerhalb eines theoretischen Modells in den Praxismaßstab übertragen, um den Einfluss auf Treibhausgasemissionen, Energiebilanz und Ökonomie zu bewerten. Die Vorbehandlungstemperaturen im Labor lagen zwischen 140 und 220°C in Schritten von 20 K und einer Vorbehandlungszeit von jeweils 5 Minuten. Die höchste Methanmehr¬ausbeute von 58 % konnte bei einer Temperatur von 180°C ermittelt werden. Das Auftreten von Inhibitoren und nicht vergärbaren Bestandteilen führte bei einer Aufbereitungstemperatur von 220°C zu Methanausbeuten, die geringer waren als die des unaufbereiteten Einsatzstoffes. In einer erweiterten Analyse konnte ein funktioneller Zusammenhang zwischen der Methanausbeute nach 30 Tagen und der Methanbildungsrate und -ausbeute während der Beschleunigungsphase gezeigt werden. Mittels einer Regressionsanalyse der so ermittelten Werte wurde nachgewiesen, dass die optimale Aufbereitungstemperatur 164°C ist und die minimale größer als 115°C zu sein hat. Treibhausgasemissionen und Energiebilanz wurden im Rahmen einer Ökobilanz nach ISO 14044 (2006) ermittelt, sowie eine Kosten-Nutzen-Analyse durchgeführt. Dazu wurde eine Anlage zur thermobarischen Vorbehandlung entwickelt und innerhalb eines Modells in eine Biogasanlage integriert. Weiterhin wurde in diesem Modell Maissilage durch Rinderfestmist und / oder Rindergülle als Einsatzstoff ersetzt. Rinderfestmist, ein Einsatzstoff mit hohem organischen Trockenmassegehalt, der ohne Vorbehandlung nicht einsetzbar wäre, erreichte eine energetische Amortisationszeit von 9 Monaten, eine Vermeidung in Höhe der während der Herstellung emittierten Treibhausgase innerhalb von 3 Monaten und eine ökonomische Amortisationszeit von 3 Jahren 3 Monaten, wohingegen Rindergülle keine positiven Effekte zeigte. / Hydrolysis and digestibility of cattle waste as feedstock for anaerobic digestion were improved by thermobarical treatment in lab-scale experiments. The effects of this improvement on greenhouse gas emissions, energy balance and economic benefit was assessed in a full-scale model application. Thermobarical treatment temperatures in lab-scale experiments were 140 to 220°C in 20 K steps for a 5-minute duration. Methane yields could be increased by up to 58 % at a treatment temperature of 180°C. At 220°C, the abundance of inhibitors and other non-digestible substances led to lower methane yields than those obtained from untreated material. In an extended analysis, it could be demonstrated that there is a functional correlation between the methane yields after 30 days and the formation rate and methane yield in the acceleration phase. It could be proved in a regression of these correlation values that the optimum treatment temperature is 164°C and that the minimum treatment temperature should be above 115°C. The theoretical application of a full-scale model was used for assessing energy balance and greenhouse gas emissions following an LCA approach according to ISO 14044 (2006) as well as economy. A model device for thermobarical treatment has been suggested for and theoretically integrated in a biogas plant. The assessment considered the replacement of maize silage as feedstock with liquid and / or solid cattle waste. The integration of thermobarical pretreatment is beneficial for raw material with high organic dry matter content that needs pretreatment to be suitable for anaerobic digestion: Solid cattle waste revealed very short payback times, e.g. 9 months for energy, 3 months for greenhouse gases, and 3 years 3 months for economic amortization, whereas, in contrast, liquid cattle waste did not perform positive replacement effects in this analysis.
198

Bifunctionalised pretreatment of lignocellulosic biomass into reducing sugars:use of ionic liquids and acid-catalysed mechanical approach

Dong, Y. (Yue) 27 October 2017 (has links)
Abstract Lignocellulosic biomass is the most abundant renewable raw material on the earth and it is so far the most suitable and promising resource for the production of biofuels to replace long-term use of fossil oil. This research aims to convert lignocellulose-based industrial residuals, fibre sludge (FS) from a pulp mill and pine sawdust (PSD) from a sawmill, into platform sugars by two different bifunctionalised pretreatments of lignocellulosic biomass. The bifunctionalised pretreatment combines the ordinary pretreatment (deconstruction) of lignocellulosic biomass with lignocellulosic polysaccharides saccharification. The outcome from both pretreatments can be further transformed into biofuels and chemicals. PSD and FS were converted into platform sugars by acid-catalysed mechanical depolymerisation in a planetary ball mill in the first part of this research. The efficiency of the conversion was mainly affected by the transferred energy caused by collisions, the total milling time, acid concentration and moisture content in the reaction. Approximately 30 wt% of the sugars was yielded from PSD and FS both in the short milling process with a low acid/substrate (A/S) concentration without any prior treatment. The second part of this research focuses upon the conversion of FS into platform sugars using hydroxyalkylimidazolium hydrogen sulphate ionic liquids (ILs). Around 29 wt% of the sugars was produced from FS using an IL/water mixture. The added water acted as a co-solvent and played a critical role in the utilisation of these ILs. The blended water reduced the viscosity of the ILs and enhanced the mass transfer between solvent and solute. In addition, the anions of the ILs provided their acidic property in an aqueous solution and offered an acidic environment for hydrolysis simultaneously. / Tiivistelmä Lignosellulossapohjainen biomassa on runsaimmin saatavilla oleva ja yksi lupaavimmista raaka-aineista biopolttoaineiden valmistukseen korvaamaan fossiilisia polttoaineita. Väitöskirjassa tutkitaan teollisuuden lignoselluloosapohjaisten sivutuotteiden, selluteollisuuden kuitulietteen ja sahateollisuuden sahanpurun (mäntypuru), muuntamista sokereiksi kahdella erilaisella ns. bifunktionaalisella esikäsittelyllä, joissa yhdistyvät lignoselluloosabiomassan perinteinen esikäsittely (hajotus) ja polysakkaridien sokeroituminen. Muodostuneet sokerit voidaan edelleen muuntaa biopolttoaineiksi ja -kemikaaleiksi. Tutkimuksen ensimmäisessä vaiheessa sahanpuru ja kuituliete muunnettiin sokereiksi happokatalysoidussa mekaanisessa käsittelyssä, joka tehtiin kuulamyllyssä. Reaktiossa katalyyttisen käsittelyn tehokkuuteen vaikuttivat erityisesti jauhatuksen kineettinen energia, jauhatusaika, happokonsentraatio ja reaktioseoksen kosteus. Tulosten perusteella todettiin, että ilman lähtöaineen esikäsittelyä sekä sahanpurun että kuitulietteen sokerisaanto oli noin 30 massa% lyhyen, matalassa happokonsentraatiossa tehdyn jauhatuksen jälkeen. Tutkimuksen toisessa vaiheessa kuituliete muutettiin sokereiksi käyttämällä ionista liuotinta (IL), hydroksialkyyli-imidatsoliumvetysulfaattia. Sokerisaanto kuitulietteestä oli noin 29 massa% IL-vesiseoksessa. Vesi toimi reaktiossa apuliuottimena ja sen rooli on keskeinen ionisten liuottimien käytössä. Sekoittunut vesi laski ionisen liuottimen viskositeettia sekä edisti aineensiirtoa liuottimen ja liukenevan aineen välillä. IL:n anionit lisäsivät happamuutta vesiliuoksessa ja mahdollistivat happamat olosuhteet samanaikaiselle hydrolyysille. / Abstract Biomasse aus Lignocellulose ist der am häufigsten vorkommende nachwachsende Rohstoff der Erde und wird aktuell als eine der besten Alternativen für die Produktion von Biokraftstoffen gesehen. Diese sollen langfristig die fossilen Öl-basierten Produkte ersetzen. Diese Forschungsarbeit untersucht die Herstellung von Zucker aus Lignocellulose basierten Abfällen. Faserschlamm aus der Zellstoffindustrie und Kiefern-Sägemehl aus der Holzverarbeitung wurden durch zwei unterschiedliche Bifunktionelle Vorbehandlungen aufgespalten. Diese Bifunktionelle Vorbehandlung kombiniert zwei Schritte in einem Prozess; die gewöhnliche Dekonstruktion der Biomasse und die Verzuckerung von Polysacchariden aus der Lignocellulose. Das so erzeugte Produkt dient als Ausgangsstoff für die weitere Herstellung von Biokraftstoffen und Chemikalien. Im ersten Teil dieser Forschungsarbeit wurden Kiefern-Sägemehl und Faserschlamm in einer Planeten-Kugelmühle zermahlen und gleichzeitig durch eine Säure depolymerisiert. Der Wirkungsgrad dieser säurekatalysierten mechanischen Depolymerisation wurde hauptsächlich durch die Übertragung der Reibungsenergie, der Mahldauer der Zerkleinerung, der Konzentration der Säure und der Feuchtegehalt der Proben beeinflusst. Etwa 30 wt% Zucker wurde so durch den kurzen Zermahlungsprozess aus Kiefern-Sägemehl und Faserschlamm gewonnen. Dabei wurden die Proben nicht vorbehandelt und enthielten eine geringe Säure/Probe Konzentration. Der zweite Teil der Forschungsarbeit untersucht die Umwandlung von Faserschlamm in Zucker mittels der Ionischen Flüssigkeit (ILs) Hydroxyalkyl Imidazolium Hydrogensulfat. Aus den Faserschlamm Proben konnte 29 wt% Zucker durch eine Mischung von ILs und Wasser gewonnen werden. Das zugesetzte Wasser spielte als Co-Lösemittel eine wichtige Rolle in der Nutzung der Ionischen Flüssigkeit, dessen Viskosität so reduziert wurde. Dies führte zu einem erhöhten Stoffübergang zwischen dem Lösemittel und dem Solvat. Zusätzlich sorgten die Anionen der Ionischen Flüssigkeit für ein saures Milieu in der wässrigen Lösung und ermöglichten so eine gleichzeitige Hydrolyse.

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