Philosophiae Doctor - PhD / Maleic acid (MA) is a key intermediate for the synthesis of polyester resins, surface coatings, lubricant additives, plasticizers, copolymers, pharmaceuticals and agricultural chemicals. The current industrial production of MA is an energy-intensive gas-phase oxidation process of n-butane. The dwindling fossil resources and environmental issues have brought about a worldwide paradigm shift from fossil feedstocks to biomass resources for the sustainable production of fuel and chemicals. Furfural (FFR) and 5-hydroxymethylfurfural (HMF) are excellent biomass-derived platform chemicals, which present an alternative route for the production of renewable bio-based MA. There has been considerable success achieved in the oxidation of furfural and HMF to maleic acid and maleic anhydride with different catalysts in recent years.

Nitrogen fertilizers are extensively used to enhance the growth of biomass crops. This study was conducted to determine the effect of N rates on the biomass yield and quality, and N uptake of several crops. The experiment was conducted at Fargo and Prosper, ND, in 2010 and 2011. The crops studied were forage sweet sorghum [Sorghum bicolor L. Moench], sorghum x sudangrass [Sorghum bicolor var. sudanense (Piper) Stapf.], kenaf [Hibiscus cannabinus L.], and reed canarygrass [Phalaris arundinacea L.]. The different crops constituted the main plots and the nitrogen rates were regarded as subplots. The five N rates were 0, 75, 100, 150, and 200 kg N ha-1. Forage sweet sorghum and sorghum x sudangrass had the greatest dry matter biomass yield. Nitrogen fertilization increased biomass yield for each of the crops. The results indicate that forage sorghum and sorghum x sudangrass have the greatest potential as a feedstock.

Diploma thesis, in its introduction, describes the expression biomass and the ways of its production from various sources, focused particularly on waste biomass In the following part it deals with the description of its origin and the advantages of its usage. It describes the usage of biomass in the world as well as in the Slovak Republic. It also looks into the possibilities of processing of biomass and the following use at heat and electricity production. In its last part this work describes, on particular examples, the usage of biomass in electricity and heat production, from businesses with high power to its usage in houses.

Orientador: Mauricio Boscolo / Banca: Devaney Ribeiro do Carmo / Banca: João Cláudio Thoméo / Resumo: Este estudo teve como foco a otimização do processo de produção de biodiesel etílico por transesterificação entre etanol e óleo de soja e catalisado por óxidos mistos derivados de materiais tipo hidrotalcita (Ox-MgAl, Ox-Lu1%, Ox-Yb1%, Ox-Zn10%Fe10% e OxW2,5%). As condições reacionais que afetam o rendimento desta reação foram investigadas. A metodologia de superfície de resposta (MSR) baseada no Planejamento Composto Central de quatro fatores em cinco níveis foi empregada em duas etapas. No primeiro planejamento experimental as variáveis do processo foram temperatura de reação, tempo de reação, razão molar etanol/óleo e massa de catalisador, enquanto que o rendimento do biodiesel foi a variável resposta principal. No segundo planejamento experimental, as variáveis do processo foram o tempo de reação e razão molar etanol/óleo, sendo a massa de catalisador e a temperatura mantidas constantes. Foram obtidos cinco modelos codificados de segunda ordem que descrevem o rendimento do biodiesel em função do tempo e da razão molar etanol/óleo de soja e as condições ótimas de cada catalisador foram encontradas. Os experimentos foram realizados sob estas condições para confirmar a validade do modelo e o maior rendimento de biodiesel etílico obtido utilizando as variáveis otimizadas. O catalisador Ox-Yb1% proporcionou o maior rendimento (83,8%) depois de 15,5 horas com razão molar etanol/óleo de soja igual a 37/1. Os valores experimentais concordaram com os resultados previstos pela MSR... / Abstract: This study focused on the optimization of the biodiesel production process by transesterification between ethanol and soybean oil and catalyzed by mixed oxides derived from hydrotalcite type materials (MgAl, MgAlLu, MgAlYb, MgAlZnFe and MgAlW). The reaction conditions that affect the yield of this reaction were investigated. The response surface methodology (MSR) based on the Central Composite Planning of four factors at five levels was employed in two steps. In the first experimental design the process variables were reaction temperature, reaction time, ethanol / oil molar ratio and catalyst mass, while the biodiesel yield was the main response variable. In the second experimental design, the process variables were the reaction time and the ethanol / oil molar ratio, the catalyst mass and the temperature kept constant. Five second order coded models were obtained that describe the biodiesel yield as a function of time and the ethanol / soybean oil molar ratio and the optimum conditions of each catalyst were found. The experiments were carried out under these conditions to confirm the validity of the model and the highest yield of ethylic biodiesel obtained using the optimized variables. The MgAlYb catalyst gave the highest yield (83.8%) after 15.5 hours with molar ratio ethanol / soybean oil equal to 37/1. The experimental values agreed with the results predicted by the MSR and the optimization models were validated / Mestre

Orientador: Rodrigo Fernando Costa Marques / Resumo: A biomassa lignocelulósica vem se destacando como uma matéria-prima essencial para a produção de muitos produtos químicos de interesse industrial em áreas como a produção de energia, alimentos, fármacos, agricultura, meio ambiente e assim por diante. Apesar disso, muitas aplicações vêm esbarrando em uma série de dificuldades encontradas nos processos de conversão enzimática, como instabilidade operação das enzimas, alto custo de produção e purificação, reações de inibição e problemas de recuperação e reciclo. Para contornar esses problemas, muitos métodos de imobilização enzimática têm surgido, entre os quais, destaca-se a obtenção de agregados enzimáticos reticulados magnéticos (MCLEAs). Esta classe de materiais é obtida a partir da reação de reticulação entre agregados físicos de enzimas e suportes magnéticos, o qual pode unir as importantes propriedades catalíticas dos agregados físicos (como resultado da manutenção da estrutura nativa da enzima) à capacidade de recuperação e reciclo do suporte magnético (devido suas propriedades magnéticas intrínsecas). Frente a isso, esse trabalho relata a síntese, caracterização e potencial aplicação de MCLEAs de enzimas celulases em processos de conversão de celulose. Dividido em três capítulos, primeiramente é apresentado um review sobre o estado da arte no que diz respeito a obtenção de produtos de valor agregado a partir da biomassa lignocelulósica utilizando MCLEAs. No segundo capítulo, diferentes MCLEAs foram preparados na presenç... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Lignocellulosic biomass has highlighted as an essential renewable raw material for production of many value-added chemicals of industrial interest in field as energy production, food, pharmaceutical, agriculture, environment and so on. Despite it, many applications have wrought with a series of difficulties in regarding enzymatic conversion processes, as enzyme operational instability, high production and purification cost, inhibition reactions, and issues of recovery and recycle. To overcome these issues, many enzyme immobilization methods have emerged, among which highlights the obtention of magnetic-cross linked enzyme aggregates (MCLEAs). This materials class is obtained from cross-linking reaction between enzyme physical aggregates and magnetic supports, which can gather the important catalytic properties of the physical aggregates (as a result of enzyme native structure maintenance) to recovery and recycle capacity of magnetic nanoparticles (as result of its intrinsic magnetic properties). Faced it, this work reports the synthesis, characterization and potential application of different cellulases MCLEAs in the cellulose enzymatic conversion process. Sectioned in three chapters, firstly is presented a review about the state of art in concern to obtention of value-added chemicals from lignocellulosic biomass using MCLEAs. In the second chapter, different MCLEAs were prepared in the presence of quitosana-coated magnetic nanoparticles with three different precipitation age... (Complete abstract click electronic access below) / Doutor

Arundo donax (Giant reed Plant) contains high level of cellulose, hemicellulose and lignin. It is used as a second generation method for the production of ethanol from lignocellulosic biomasses. Cellulose molecules comprised an unbranched polymer of 1,000 to 1,000,000 D-glucose linking units coupled with beta-1, 4 glycosidic bonds. Microorganism present in beta 1-4 gluconase breaks down the glucosidic linkage in the Microcrystalline structure of the cellulose to cellobiose molecules (a glucose dimer have a beta-1, 4 bond). The cellobiose is subsequently broken down into glucose molecules by an enzyme called beta-glucosidase. The scope of this work entails hydrolysis conversion of cellulose to glucose and other value added products using enzymatic (Cellulase)

No description available.

With the increasing need for renewable energy technologies in the world, biomass fuel transformation technology is growing towards meeting that need, among others. Challenges remain certain and new innovations are being tested in bid to overcome them with the application of biomass as energy source. This report presents some studies carried out into understanding the potential and challenges associated with utilization of biomass fuel, especially for technologies that are appropriate for rural applications.  Utilization of biomass gasification technologies is in the focus of this study.   The great potential biomass fuel provide to Uganda for possible energy production in small scale application is presented. This study was carried out to understand the possibility of using biomass as fuel in electricity power generation in Uganda. It takes into consideration the use of biomass gasification technology in energy production. Challenges related to the application of biomass fuels are discussed, mostly with tar and alkali metal compounds in the gas stream.   Suggested methods to combat some of the challenges with biomass fuels are pointed out in this study. Application of externally fired gas turbine (EFGT) system is a particular approach discussed and its technical performance analyzed.  The analysis revealed that efficiency of the EFGT system is greatly dependent on the heat exchanger effectiveness and on turbine inlet temperature. Optimum performance can be realized with air compression ratio of 3.4. It is also noted that fouling and deposition in the heat exchanger can affect its performance.   A related study carried out was on the retention of alkali metals in an updraft gasifier. The gasifier was chosen for possible integration with the EFGT system. Finding was that about 99% of the alkali metals are retained in the gasifier. It is anticipated that this would reduce on the deposition in the heat exchanger, reducing on maintenance time. A need is identified to determine the level of deposition mentioned. A simple thermodynamic modeling of the alkali metals condensation reaction on a high temperature heat exchanger surface was conducted. The results showed that with appropriate quantity of S in the raw fuel, alkali metals bounding with Cl are greatly reduced. Cl is passed out as gaseous HCl, leaving deposition of none corrosive sulphates. Recommendation is made to study this phenomenon in an experimental setting.   Biomass gasification technology integration with an internal combustion (IC) engine is also studied. Here requirements for the producer gas quality have been discussed. Some tests carried out with wood pellets and wood cylinders compared the yield of tar from the two physically different fuels.  Wood pellets were found to yield more tar than wood cylinders.   Economic analysis of biomass gasifier integrated with an IC engine running a generator of 100 kWe was carried out. Comparison with a diesel electricity generator of similar capacity was made for a scenario in Uganda over a project life of 20 years. Different Plant Capacity Factors (PCF) and fuel costs including subsidies were considered. The analysis showed that over long period of time biomass power plant was more beneficial than the diesel power plant at PCF over 40%. This is more pronounced with unsubsidized diesel fuel. / QC 20111206

faculty of Science School of Molecular and Cell Biology 9605145v vhaakuria@yahoo.co.uk / Cassava is a food crop planted in many countries in Africa. Its tubers are a major source of food and are processed to produce a variety of food products, one of which is the fermented product called gari. This research report aimed to evaluate the performance of three lactic acid bacteria for several properties with regard to the fermentation of cassava to produce gari. Three organisms were used for the evaluation, namely Lactobacillus plantarum, Lactobacillus fermentum and Leuconostoc mesenteroides. The organisms were evaluated for viability, biomass formation and glucose utilisation in static flasks, biomass formation and glucose utilisation in 2 L fermenters, cell viability after dehydration processes and pH and cyanide reduction in cassava substrate. In static flasks, the organisms were found to retain above 80% cell viability after cryopreservation. Maximum biomass of 108 cells/ml was formed within the first 12 hours by all the organisms. While L. fermentum, depleted glucose within 24 hours, L. plantarum formed the highest biomass of 4 x 108 cells/ml. In 2 L Braunstat B fermenters, a cell count of 109 cells/ml was obtained by L. fermentum and Leuconostoc mesenteroides within 12-15 hours. Biomass formation for L. plantarum during the same period was 1010 cells/ml. Glucose was depleted within 12 - 15 hours. The viability of cells between the dehydration processes of centrifugation, glycerol and maltodextrin addition and lyophilisation, was above 80% for all the organisms. However, this high cell viability was influenced by concentration of cells during the centrifugation step. In cassava substrate, L. fermentum, though heterofermentative, was found to be particularly acid tolerant and reduced pH to 3.98. All the organisms were able to retain good viability after lyophilisation. However, the results of cyanide reduction were inconclusive. These results show that while cultures show promise for pilot scale studies of starter culture development, further cyanide experiments need to be conducted, and synergy between the organisms investigated.

京都大学 / 新制・課程博士 / 博士(エネルギー科学) / 甲第23292号 / エネ博第417号 / 新制||エネ||79(附属図書館) / 京都大学大学院エネルギー科学研究科エネルギー社会・環境科学専攻 / (主査)教授 河本 晴雄, 教授 石原 慶一, 教授 上髙原 浩 / 学位規則第4条第1項該当 / Doctor of Energy Science / Kyoto University / DFAM