Barley spent grain, the main residue of the brewing industry, is a lignocellulosic material, which could be considered a potential raw material for ethanol production. In this work, spent grains generated in a microbrewery were fractionated by acid hydrolysis and delignification. The investigated sort of barley spent grains had high carbohydrate content, accounting for 60% of the dry matter, while its lignin content was lower than that reported for other sorts of spent grains. Since the used spent grains contained residual starch different treatment approaches were used for separating their main components without affecting the sugars generated by starch hydrolysis. Two kinds of acid hydrolysis processes, namely single-step and two-step hydrolysis, were used for solubilising the carbohydrate fraction. Single-step hydrolysis was performed either at 100oC or at 121oC. In the two-step approach, a second hydrolysis, at 121oC, was performed after the first hydrolysis step. The dilute-acid hydrolysis at 100oC removed all the starch, whereas the hydrolysis at 121oC removed also a part of the hemicelluloses in addition to starch. During the second hydrolysis step, the content of easily hydrolysable polysaccharides decreased from 32.5 to 7.6% in the material pre-hydrolyzed at 100oC and from 20.3 to 10.6% in the material pre-hydrolyzed at 121oC. The amount of easily hydrolysable polysaccharides removed in the second step corresponded to 83% and 81.5% of the total removed matter in the materials pre-hydrolyzed at 100 and 121oC, respectively. In the next step, acetosolv and alkaline delignification, either alone or combined with acid hydrolysis, were used for dissolving the lignin fraction. A higher solubilisation occurred after alkaline delignification, where 83% of the initial material was removed. Only 34% of the initial lignin was removed by direct acetosolv, while the combined acid hydrolysis/acetosolv approach resulted in lignin removal between 70 and 75%. However, the resulted pulp still contained important amount of lignin. The acid prehydrolysis was also beneficial for alkaline delignification, but the effect was less noticeable than for acetosolv. Lignin removal increased from 95% in direct alkaline delignification to nearly 100% in the acid hydrolysis-assisted alkaline treatment. Two different methods were carried out for lignin precipitation. In the liquid fraction obtained by acetosolv, lignin was precipitated by water addition after concentration of the liquors to 75% of the initial volume. Although the visual inspection of the liquors after water addition revealed a relatively good lignin precipitation, the separation by filtration of the precipitated material was difficult, apparently due to the small particle size of precipitated lignin molecules. Some improvement was observed for the combined treatments, especially for those including two-step acid hydrolysis. The best recovery, 54% of the precipitated lignin, occurred for the process including consecutive acid hydrolyses at 100 and then at 121oC before acetosolv. In the alkaline liquors, lignin was precipitated by pH adjustment to 2.0 by HCl. Around 40.5% of the solubilised lignin was precipitated, and it increased to 85-100% when combined treatments were applied. The best results were achieved upon the treatment including acid prehydrolysis at 121oC before alkaline process.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-04-24T16:38:21Z No. of bitstreams: 1 SHÂMIA BORBOREMA CABRAL - TESE PPGEP 2014..pdf: 2568406 bytes, checksum: 49c874b9a297e3b182edc28e1539bc52 (MD5) / Made available in DSpace on 2018-04-24T16:38:21Z (GMT). No. of bitstreams: 1 SHÂMIA BORBOREMA CABRAL - TESE PPGEP 2014..pdf: 2568406 bytes, checksum: 49c874b9a297e3b182edc28e1539bc52 (MD5) Previous issue date: 2014-07-07 / Capes / Atualmente, a matriz energética brasileira centraliza toda a sua produção de bioetanol a partir da cana-de-açúcar, no entanto, tendo em vista a vasta biodiversidade encontrada em seu território, o Brasil dispõe de uma grande variedade de resíduos agrícolas e agroindustriais cujo bioprocessamento para a produção de bioetanol desperta um grande interesse econômico e social. Nesse contexto, a presente pesquisa teve como objetivo estudar o aproveitamento de sementes de jaca (resíduo) como fonte de amido para a produção de bioetanol. Visando à máxima remoção do amido presente nas sementes de jaca, as mesmas foram submetidas a etapas de extração e purificação. Parâmetros físico-químicos foram determinados tanto para as sementes quanto para o amido extraído das sementes de jaca. O material amiláceo obtido foi, então, submetido a tratamentos hidrolíticos, empregando os ácidos sulfúrico e fosfórico como catalisadores, seguindo um planejamento fatorial completo 23 com três pontos centrais. Foram definidas como variáveis independentes, a temperatura (80, 100 e 120 °C), o tempo de reação (30, 60 e 90 min.) e a concentração do ácido (1, 3 e 5%), e como variáveis dependentes, as concentrações de glicose e hidroximetilfurfural (g.L1 ) presentes nos licores hidrolisados. A fim de observar e avaliar o efeito dos tratamentos ácidos, realizados nas condições otimizadas de operação, sobre a superfície dos grânulos do amido extraído de sementes de jaca, a técnica de microscopia eletrônica de varredura (MEV) foi empregada. Os licores hidrolisados pelos ácidos sulfúrico e fosfórico, obtidos nas condições otimizadas de operação, foram submetidos a ensaios fermentativos em uma câmara incubadora com agitação orbital a 160 rpm, sob temperatura controlada de 32 ºC, empregando como microrganismo, a levedura industrial Saccharomyces cerevisiae Y904, e como nutrientes, o composto nutricional industrial Nitrofós. O material amiláceo extraído das sementes de jaca apresentou elevado teor de amido (85,5%). Maiores concentrações de glicose, 32,98 e 31,23 g.L-1 para os tratamentos hidrolíticos com os ácidos sulfúrico e fosfórico, respectivamente, concomitantemente, com concentrações de hidroximetilfurfural (HMF) que não inibissem o processo fermentativo, 0,53 e 0,08 g.L-1 para os tratamentos com os ácidos sulfúrico e fosfórico, respectivamente, foram encontradas no ensaio executado nas condições mais severas estabelecidas para a matriz de planejamento, sendo elas: 120 °C, concentração do ácido a 5% e 90 min. de reação. O tratamento hidrolítico do amido conduzido com o ácido sulfúrico apresentou maior eficiência de hidrólise (70,13%) quando comparada a eficiência alcançada pelo tratamento empregando-se o ácido fosfórico (66,41%). As micrografias revelaram os aspectos morfológicos característicos dos grânulos de amido de sementes de jaca, constatando-se formatos, predominantemente, elipsoides e hemisféricos, e tamanhos variando de 4 a 9 μm, bem como suas modificações estruturais causadas pela ação dos ácidos durante os tratamentos hidrolíticos. Os ensaios fermentativos realizados com os licores hidrolisados pelos ácidos sulfúrico e fosfórico apresentaram eficiências de fermentação de 97,85 e 95,89%, respectivamente, indicando, portanto, que a levedura foi capaz de metabolizar, praticamente, todo o substrato limitante (glicose) presente nos licores em etanol. Considerando os resultados obtidos em todas as etapas realizadas durante a presente pesquisa, conclui-se que o amido extraído de sementes de jaca apresentou-se como uma matéria-prima promissora para a produção de bioetanol. / Currently, the Brazilian energy matrix centralizes all their production of bioethanol from sugar cane, however, in view of the vast biodiversity found in its territory, Brazil has a wide variety of agricultural and agro-industrial waste whose bioprocessing for bioethanol production arouses a great economic and social interest. In this context, the present research was to study the use of jackfruit seeds (residue) as a source of starch for the production of bioethanol. For ultimate removal of this starch in jackfruit seeds, they were subjected to extraction and purification steps. Physical and chemical parameters were determined for both the seeds and the starch extracted from jackfruit seeds. The starch material obtained was then subjected to hydrolytic treatments using sulfuric and phosphoric acids as catalysts, following a full 23 factorial design with three central points. We defined as independent variables the temperature (80, 100, 120 °C), the reaction time (30, 60 and 90 min.) and the concentration of the acid (1, 3 and 5%), the dependent variables were the glucose concentrations and hydroxymethylfurfural (g.L-1) present in the hydrolyzed liquor. In order to observe and evaluate the effect of acid treatments, based on the optimized operating conditions on the surface of starch granules extracted from jackfruit seeds, scanning electron microscopy technique (SEM) was used. The liquors hydrolyzed by sulfuric and phosphoric acids, obtained in the optimized operating conditions, underwent fermentation trials in a dry incubator with orbital shaking at 160 rpm, under controlled temperature of 32 °C, using industrial yeast Saccharomyces cerevisiae Y904 as microorganism, and the industrial nutritional compound Nitrophós as nutrients. The starch material extracted from jackfruit seeds showed high starch content (85.5%). We found higher concentrations of glucose, 32.98 and 31.23 g.L-1 to hydrolytic treatment with sulfuric and phosphoric acids respectively, concurrently, with concentrations of hydroxymethylfurfural (HMF) which would not inhibit the fermentative process, 0.53 and 0, 08 g.L-1 for treatment with sulfuric and phosphoric acids, respectively. These were found in the test run under the most severe conditions attached to the planning matrix, namely, 120 °C, 5% acid concentration and 90 min. reaction. The hydrolytic treatment of starch conducted with sulfuric acid hydrolysis showed higher efficiency (70.13%) compared to treatment efficiency achieved by employing phosphoric acid (66.41%). The micrographs revealed the characteristic morphology of jackfruit seed starch granules, confirming hemisphere and ellipsoid formats, and sizes ranging from 4 to 9 μm, as well as its structural modifications caused by the action of acid during the hydrolytic treatment . The fermentation trials with liquors hydrolyzed by sulfuric and phosphoric acids showed fermentation efficiencies of 97.85 and 95.89%, respectively, thus indicating that the yeast was capable of metabolizing substantially all the limiting substrate (glucose) present in liquors from ethanol. Considering the results obtained in all steps undertaken during this research, it is concluded that the extracted starch jackfruit seeds appeared as a promising raw material for the production of bioethanol.

Made available in DSpace on 2014-06-11T19:27:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-07-03Bitstream added on 2014-06-13T20:35:17Z : No. of bitstreams: 1 santos_ir_me_guara.pdf: 1112042 bytes, checksum: eab870d2573cb36f34ff06ab2d272f92 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A indústria de papel é a principal consumidora de caulim, contribuindo com cerca de 45% do mercado mundial. Sua maior utilização no papel é como enchimento, devido ao fato de ser mais barato do que a polpa celulósica. O processo de preparação da celulose conhecido como branqueamento é determinante nas características da polpa final. Muito esforço tem sido feito para que processos de branqueamento menos tóxicos sejam viabilizados. O principal objetivo do presente estudo foi averiguar se a sequência de branqueamento influi na retenção de caulim e avaliar sua influência nas propriedades do papel formado. Para tanto, foram adotadas três sequências de branqueamento para uma mesma polpa de madeira de eucalipto, sendo duas delas do tipo ECF e a outra do tipo ECF-Light. As polpas foram branqueadas até a obtenção aproximada de 90 ± 0,5% ISO de alvura. Posteriormente, foram feitos repetidos testes por tentativa e erro para que fosse feita a substituição de fibra por caulim do tipo filler de 0 a 35% com intervalos de 5%, em termos de massa, para cada polpa. As folhas formadas foram caracterizadas física, mecânica e oticamente. Também foram analisadas as dimensões das fibras obtidas por cada sequência de branqueamento. Os resultados mostraram que a sequência de branqueamento influi tanto na retenção, devido ao tamanho e ao teor de finos gerados por cada sequência de branqueamento, bem como nas propriedades óticas, mecânicas e físicas do papel formado para cada teor de caulim. A sequência ECF-Light apresentou melhor retenção de caulim e seu papel apresentou melhores resultados de lisura, enquanto que a sequência OAHTD(E+P)DP levou a polpas de papel com maior resistência interna e maior resistência à compressão. A polpa referência apresentou melhores resultados de índice de rasgo, viscosidade, rendimento e qualidade de fibra / The paper industry is the main consumer of kaolin, contributing about 45% of the world. Its greatest use is as filler in paper, due to being cheaper than the pulp. The process of preparing the pulp bleaching process is known as determining the characteristics of the final pulp. Much effort has been made to less toxic bleaching processes are enabled. The main objective of this study was to determine if the bleaching sequence influences the retention of kaolin and its influence on the properties of paper formed. Thus, we adopted three bleaching sequences for the same eucalyptus pulp, two ECF types and the other ECF-Light. The pulps were bleached to obtain approximately 90 ± 0.5% ISO brightness. Later, we made repeated testing by trial and error that was made for the replacement of kaolin by type fiber filler 0 to 35% in increments of 5% for each pulp. Finally, the sheets formed were characterized physically, mechanically and optically. We also analyzed the dimensions of the fibers obtained by each sequence of bleaching. The results showed that the sequence of bleaching both affect the retention due to the size and content of fines generated by each sequence of bleaching, as well as in optical, mechanical and physical properties of paper formed for each concentration of kaolin. The ECF-Light OAHTD(E + P)P sequence showed a better smoothness, whereas the sequence OAHTD0 (E + P) D1P showed a better internal resistance and compressive strength. The reference pulp (OD0(E+P)D1P) showed better results for tear index, viscosity, yield and fiber quality (length, width, coarseness and fines content)

Master of Science / Department of Grain Science and Industry / Yong Cheng Shi / Waxy wheat starch (WWS) containing little or no amylose has unique properties for food and industrial uses. Hydroxypropylation, a widely used means for modifying starches, could enhance functionalities of starch by substituting hydroxyl groups in starch. There are limited numbers of literatures regarding hydroxypropylation of WWS. WWS hydroxypropylated with 3.0-9.0% propylene oxide (PO) were prepared and compared to hydroxypropylated normal wheat starch (NWS) and hydroxypropylated waxy maize starch (WMS). The molar substitution (MS) of the resulting hydroxypropylated NWS, WWS and WMS was 0.055-0.151, 0.048-0.133, and 0.049-0.139, respectively. Gelatinization temperatures and enthalpy of hydroxypropylated starches were significantly lower than those of their unmodified counterparts and the extent of decrease was positively correlated to the MS. Differential scanning colorimetry (DSC) results showed that hydroxypropylation reduced the retrogradation of the starches during the storage after gelatinization but there were differences between the starches. For the same level of PO reaction (3 and 5% PO), hydroxypropylated WWS retrogradated less than hydroxypropylated WMS, suggesting that for the same level of cold storage stability, less PO is needed for WWS. After reacted with 6% PO, MS was 0.092 and 0.094, respectively, for WWS and WMS, and no retrogradation was observed for those hydroxypropylated starches, indicating that at MS ~0.094, hydroxypropyl groups prevents amylopectin chains from re-associating and forming crystalline structures. In contrast, a higher level of PO (9%) was needed to react with NWS to achieve the hydroxypropylated starch with an MS of 0.151 that gave no retrogradation. Consistent with microscopic observation results, Micro-Visco-Amylograph (MVA) analysis showed hydroxypropylated starches developed viscosity at lower temperatures and had improved hot and cold viscosities. The specific characteristics of hydroxypropylated starches are related to the degree of hydroxypropylation. Therefore, it is critical to determine the level of hydroxypropylation in modified starches. 1H NMR is a simple and rapid means of determining hydroxypropyl (HP) group in modified starches. In this study, a method to prepare a HP starch for NMR analysis was improved. The optimum parameters proposed to hydrolyze HP starches were 10% starch solid content, 3.5% (wt.%) DCl in D2O as the solvent, sodium acetate as an internal standard, heating at 90oC for 1 h. Optionally, 6% (v/v) trifluoroacetic acid-d as the water-peak shifting reagent. Six hydroxypropylated starch samples and two commercial cross-linked and hydroxypropylated starch samples were hydrolyzed with this modified method before 1H NMR analysis, and the results of HP group content in the samples were in agreement with the results from an enzyme-catalyzed method, which indicate that the improved acid hydrolysis method is applicable for both hydroxypropylated starch and cross-linked and hydroxypropylated starch.

Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-12-01T18:14:50Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) philipe_luan_brito.pdf: 1575319 bytes, checksum: fbec2867a577d1c18c943afc8609f8e3 (MD5) / Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-12-01T18:31:07Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) philipe_luan_brito.pdf: 1575319 bytes, checksum: fbec2867a577d1c18c943afc8609f8e3 (MD5) / Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-12-01T18:34:02Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) philipe_luan_brito.pdf: 1575319 bytes, checksum: fbec2867a577d1c18c943afc8609f8e3 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-12-01T18:34:15Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) philipe_luan_brito.pdf: 1575319 bytes, checksum: fbec2867a577d1c18c943afc8609f8e3 (MD5) / Made available in DSpace on 2016-12-01T18:34:15Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) philipe_luan_brito.pdf: 1575319 bytes, checksum: fbec2867a577d1c18c943afc8609f8e3 (MD5) Previous issue date: 2016 / Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG) / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Nas ?ltimas d?cadas tem se intensificado o estudo de estrat?gias que proporcionem melhores rendimentos em etanol a partir do uso de biomassas lignocelul?sicas. Neste trabalho foi utilizado o res?duo agroindustrial do processo de beneficiamento do ?leo do dend? (Elaeis guineensis) para obten??o de um hidrolisado ?cido hemicelul?sico para posterior fermenta??o. O hidrolisado foi obtido atrav?s da utiliza??o de ?cido sulf?rico dilu?do o qual se mostrou eficiente na solubiliza??o da hemicelulose. Tr?s m?todos de destoxifica??o dos inibidores foram testados dentre os quais se destacaram os tratamentos por carv?o ativado e a combina??o do tratamento empregando overliming e carv?o ativado, com remo??o de compostos fen?licos, furfural e 5-hidroximetilfurfural acima de 90% do hidrolisado. As linhagens de Scheffersomyces stipitis NRRLY 1214 e NRRLY 7124 apresentaram os maiores valores de etanol, com valores correspondentes de 6,2 e 6,13 g L-1, no meio destoxificado por overliming com suplementa??o. Estas linhagens, neste mesmo meio, alcan?aram as maiores taxas de Yp/s (0,32 e 0,33) e Ef (64,46 e 64,89%). Os dados obtidos corroboram que as linhagens estudadas apresentam potencial para a fermenta??o da fra??o hemicelul?sica da torta de dend?. O uso de meio de hidrolisado ?cido da torta de dend?, sem suplementa??o, se mostra invi?vel nas condi??es testadas, pois reflete em valores insignificantes de etanol. Os dados obtidos contribuir?o de forma positiva no aproveitamento de res?duos agroindustriais, bem como para os avan?os na ?rea de obten??o de etanol de segunda gera??o. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Biocombust?veis, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / In recent decades, the study of strategies that provide better yields in ethanol from lignocellulosic biomass has intensified. In this study we used the agroindustrial residue from the palm oil milling process (Elaeis guineensis) to obtain an acid-hydrolyzed hemicellulose for fermentation. The hydrolyzate was obtained using dilute sulfuric acid, which was efficient at dissolving the hemicellulose. Three methods of detoxification of inhibitors were tested, including the use of activated carbon treatment and a combination treatment employing overliming and activated carbon. Greater than 90% of the phenolic substances, furfural and 5-hydroxymethylfurfural were removed from the hydrolysis product. The NRRLY 1214 and NRRLY7124 strains of Scheffersomyces stipitis produced the highest yields of ethanol, 6.2 and 6.13 g L-1, in the medium detoxified by the overliming procedure. These strains achieved the highest rates of Yp / s (0.32 and 0.33) and Ef (64.46 and 64.89%) in the same medium. The data confirm that these strains have a potential for fermentation of the hemicellulose fraction of palm kernel cake. The use of the acid hydrolyzate of palm kernel cake without supplementation was shown to be unfeasible under the conditions tested, as reflected in the insignificant yields of ethanol. The data obtained will contribute positively to the use of agro-industrial waste, as well as to advances in the area of the production of second-generation ethanol.

Data de aprova??o ausente. / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-02-02T17:06:42Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) philipe_luan_brito.pdf: 1575319 bytes, checksum: fbec2867a577d1c18c943afc8609f8e3 (MD5) / Rejected by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br), reason: Faltou fomento on 2017-02-02T18:12:58Z (GMT) / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-02-02T18:30:10Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) philipe_luan_brito.pdf: 1575319 bytes, checksum: fbec2867a577d1c18c943afc8609f8e3 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-03-06T15:07:41Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) philipe_luan_brito.pdf: 1575319 bytes, checksum: fbec2867a577d1c18c943afc8609f8e3 (MD5) / Made available in DSpace on 2017-03-06T15:07:41Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) philipe_luan_brito.pdf: 1575319 bytes, checksum: fbec2867a577d1c18c943afc8609f8e3 (MD5) Previous issue date: 2016 / Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG) / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Nas ?ltimas d?cadas tem se intensificado o estudo de estrat?gias que proporcionem melhores rendimentos em etanol a partir do uso de biomassas lignocelul?sicas. Neste trabalho foi utilizado o res?duo agroindustrial do processo de beneficiamento do ?leo do dend? (Elaeis guineensis) para obten??o de um hidrolisado ?cido hemicelul?sico para posterior fermenta??o. O hidrolisado foi obtido atrav?s da utiliza??o de ?cido sulf?rico dilu?do o qual se mostrou eficiente na solubiliza??o da hemicelulose. Tr?s m?todos de destoxifica??o dos inibidores foram testados dentre os quais se destacaram os tratamentos por carv?o ativado e a combina??o do tratamento empregando overliming e carv?o ativado, com remo??o de compostos fen?licos, furfural e 5-hidroximetilfurfural acima de 90% do hidrolisado. As linhagens de Scheffersomyces stipitis NRRLY 1214 e NRRLY 7124 apresentaram os maiores valores de etanol, com valores correspondentes de 6,2 e 6,13 g L-1, no meio destoxificado por overliming com suplementa??o. Estas linhagens, neste mesmo meio, alcan?aram as maiores taxas de Yp/s (0,32 e 0,33) e Ef (64,46 e 64,89%). Os dados obtidos corroboram que as linhagens estudadas apresentam potencial para a fermenta??o da fra??o hemicelul?sica da torta de dend?. O uso de meio de hidrolisado ?cido da torta de dend?, sem suplementa??o, se mostra invi?vel nas condi??es testadas, pois reflete em valores insignificantes de etanol. Os dados obtidos contribuir?o de forma positiva no aproveitamento de res?duos agroindustriais, bem como para os avan?os na ?rea de obten??o de etanol de segunda gera??o. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Biocombust?veis, Universidade Federal dos Vales do Jequitinhonha e Mucuri, [2016]. / In recent decades, the study of strategies that provide better yields in ethanol from lignocellulosic biomass has intensified. In this study we used the agroindustrial residue from the palm oil milling process (Elaeis guineensis) to obtain an acid-hydrolyzed hemicellulose for fermentation. The hydrolyzate was obtained using dilute sulfuric acid, which was efficient at dissolving the hemicellulose. Three methods of detoxification of inhibitors were tested, including the use of activated carbon treatment and a combination treatment employing overliming and activated carbon. Greater than 90% of the phenolic substances, furfural and 5-hydroxymethylfurfural were removed from the hydrolysis product. The NRRLY 1214 and NRRLY7124 strains of Scheffersomyces stipitis produced the highest yields of ethanol, 6.2 and 6.13 g L-1, in the medium detoxified by the overliming procedure. These strains achieved the highest rates of Yp / s (0.32 and 0.33) and Ef (64.46 and 64.89%) in the same medium. The data confirm that these strains have a potential for fermentation of the hemicellulose fraction of palm kernel cake. The use of the acid hydrolyzate of palm kernel cake without supplementation was shown to be unfeasible under the conditions tested, as reflected in the insignificant yields of ethanol. The data obtained will contribute positively to the use of agro-industrial waste, as well as to advances in the area of the production of second-generation ethanol.

The presented dissertation assesses the technological and economical use of high-pressure hydrolysis of wheat straw with sulfuric acid (H2SO4) for biogas producing. The theoretical part is focusing to the structure of lignocellulosis phytomass, on technology of mechanical treatment and acid hydrolysis. The experimental part is based on the production of neutralized hydrolyzate obtained by using technology of high-pressure hydrolyse by pressure 1,5 MPa, in retention time of 500 seconds and 190 °C. Data, generated by operation server Linode Platform Manager, emerges, that the area with the best polynormal cubic function, which is aproximated by the smallest mistake. The local extremes, where are the verification of the cumulative CH4 by anaerobic fermentation (in thermophilic area by temperature 51 °C) in relation on dry matter, are calculated of tha data obtained of Maple 14. The highest yeld of CH4 production was found by pressure of high-pressure hydrolyser 2,37 MPa. The maximum value of production of biogas (CH4) was 190 m3. t-1 of dry phytomass. Based on the optimalization, was maximum yeld of CH4 (of biochemical aspects) found about dry matter 8,57 % and pH 4,84. From the managerial point of view, which takes into account technological limitations and financial indicator, are the optimal conditions by dry matter from 3,92 to 5,12 % and a pH of 3,2 to 5,1.

A crescente demanda por tecnologias que produzam biocombustíveis de maneira sustentável vem incentivando a utilização de diversos materiais lignocelulósicos para tal finalidade. O objetivo deste trabalho foi comparar o potencial de produção de açúcares (glicose e xilose) da palha e do bagaço de cana-de-açúcar. Inicialmente, as duas biomassas foram caracterizadas, mostrando percentuais muito similares de celulose e hemicelulose (42,1% e 22,6% para o bagaço e 39,2% e 22,7% para a palha, respectivamente). Isto evidencia potenciais similares de produção de açúcares. Posteriormente, foram realizados experimentos em laboratório para comparar os resultados de rendimento de xilose e produção de furfural após as reações de hidrólise ácida das duas biomassas, com o intuito de verificar se este processo, comumente utilizado para o bagaço, pode ser utilizado para a palha. As variáveis que foram avaliadas foram a concentração de ácido (0,5-3,0%m/m), o tempo reacional (15-60min) e a relação sólido-líquido (RSL - 0,1-0,2m/m). Concentrações de 42,72g/L e de 41,31g/L de xilose foram encontradas para a palha e para o bagaço, respectivamente, alcançando rendimentos de xilose superiores a 80%, em reações em laboratório. Também foram realizados ensaios de hidrólise ácida em planta piloto e de hidrólise enzimática em laboratório para avaliar os resultados de rendimento de glicose da palha. Os resultados de rendimento de xilose e produção de inibidores para estas reações foram avaliados e comparados com os dados obtidos em laboratório. Concentrações de 35,2g/Lde xilose e de 27,3g/L de glicose foram encontradas para a palha, alcançando rendimentos de xilose próximos a 100% e de glicose superiores a 64%, em reações de pré-tratamento em planta piloto e em reações de hidrólise enzimática em laboratório. Os resultados evidenciaram que as variáveis concentração de ácido e relação sólido:líquido são as mais influenciam na produção de xilose e glicose / The growing demand for technologies that produce sustainable biofuels encourages the use of various lignocellulosic materials for this purpose. The aim of this study was to compare the potential production of sugars (glucose and xylose) from sugarcane straw and bagasse. First, the biomasses were characterized, showing very similar percentage of cellulose and hemicellulose (42.1% and 22.6% for the bagasse and 39.2% and 22.7% for the straw, respectively). This is a evidence that the potential of sugar production for bagasse and straw are almost the same. Laboratory experiments were carried out to compare the results of xylose yield and production of furfural after acid hydrolysis reactions for both biomasses in order to determine whether this process, commonly used for bagasse, can be used for straw. The variables that were evaluated were acid concentration (0.5 to 3.0 wt.%), reaction time (15-60min) and liquid-solid ratio (RSL - 0.1-0.2 wt.%). Concentrations of 42.72 g/L to 41.31 g/L of xylose were found to straw and bagasse, respectively, reaching xylose yields higher than 80% in laboratory reactions. Also acid hydrolysis reactions in pilot plant and enzymatic hydrolysis reactions in laboratory were carried out to evaluate the results of straw glucose yields. Also the results of xylose yields and production of inhibitors for these reactions were evaluated and compared to the data obtained in the laboratory. Concentrations of 35.2g/L of xylose and 27.3g/L of glucose were found for straw, reaching xylose yields close to 100% and glucose yields up to 64%, in pretreatment reactions in pilot plant and in enzymatic hydrolysis reactions in the laboratory. It was observed that acid concentration and solid: liquid ratio are the variables that most influence in the results of formation of xylose and glucose

Orientador: Célia Maria Landi Franco / Banca: Maria Victória Eiras Grossmann / Banca: Maria de Lourdes Corradi Custódio da Silva / Resumo: Amido é um polímero semicristalino constituído basicamente por amilose e amilopectina. Seus grânulos são formados por regiões amorfas intercaladas com áreas mais densas compostas por lamelas alternadas de material cristalino e amorfo. O empacotamento das moléculas no grânulo é dependente da fonte botânica. Raízes e tubérculos são ricos em amido e seu plantio não requer muito investimento. Assim, o interesse industrial vem aumentando. O conhecimento da estrutura granular é fundamental para melhor entendimento das propriedades funcionais e melhor utilização do amido. A hidrólise ácida é uma técnica muito utilizada no estudo da estrutura do amido. O tratamento do amido com H2SO4 15% produz uma fração ácido-resistente, com baixa massa molar, conhecida como dextrina Naegeli (DN). O objetivo deste trabalho foi determinar a estrutura granular dos amidos de mandioca, batata, batata-doce e mandioquinha-salsa através da hidrólise ácida. Os amidos foram incubados com H2SO4 15,3% a 38ºC, por até 30 dias, e suas DN foram analisadas. A hidrólise ácida ocorreu em duas etapas: a primeira foi atribuída à rápida degradação das áreas amorfas dos grânulos, enquanto a segunda fase correspondeu à lenta hidrólise das regiões cristalinas. O amido de mandioquinha-salsa foi o mais suscetível à hidrólise, enquanto que os amidos de batata e batata-doce foram os mais resistentes. Os amidos de batata e mandioquinha-salsa apresentaram padrões cristalinos tipo B e mostraram maiores proporções de cadeias laterais longas da amilopectina (GP 37) do que os amidos de mandioca (tipo CA) e batata-doce (tipo C). Além de grande proporção de cadeias longas, o amido de mandioquinha-salsa também apresentou grande proporção de cadeias curtas (32,0%). O amido de mandioca também apresentou grande proporção de cadeias curtas (30,5%). Esses amidos mostraram um ombro em GP 17-21 ...(Resumo com'pleto, clicar acesso eletrônico abaixo) / Abstract: Starch is a semi-crystalline polymer composed mainly of amylose and amylopectin. The starch granules are formed by successive layers that include amorphous areas interspersed with more dense areas composed of alternated lamellae of crystalline and amorphous material. Packing of amylose and amylopectin into granules is dependent of botanical source. Tubers and roots are rich in starch and their cultivation does not require much investment. Thus, the industrial interest has increased. Knowledge of the starch structure is fundamental for better understanding the functional properties and better utilization of the starch. Acid hydrolysis is widely used to study starch structure. Treatment of starch with 15% H2SO4 solution produces an acid-resistant fraction with low molecular weight known as Naegeli dextrin (ND). Objective of this study was to determine the structural characteristics of cassava, potato, sweet potato and Peruvian carrot starches by using acid hydrolysis. The starches were submitted to 15.3% H2SO4 at 38ºC for up to 30 days and their ND were analyzed. Acid hydrolysis displayed two phases: the first one was attributed to faster degradation of amorphous areas of granules, whereas the second phase corresponded to slower hydrolysis of crystalline regions. Peruvian carrot starch was the most susceptible to hydrolysis, whereas potato and sweet potato starches were the most resistant. Potato and Peruvian carrot starches displayed B-type X-ray pattern and had larger proportions of long branch-chains of amylopectin (DP 37) than cassava (CA-type) and sweet potato (C-type) starches. Beyond the great proportion of long branch-chains, the Peruvian carrot starch also showed great proportion of short branch-chains (32.0%). Cassava starch also had great proportion of short branch-chains (30.5%). These starches displayed a shoulder at DP 17-21 on branch chain-length distribution... (Complete abstract click electronic access below) / Mestre

A crescente demanda por tecnologias que produzam biocombustíveis de maneira sustentável vem incentivando a utilização de diversos materiais lignocelulósicos para tal finalidade. O objetivo deste trabalho foi comparar o potencial de produção de açúcares (glicose e xilose) da palha e do bagaço de cana-de-açúcar. Inicialmente, as duas biomassas foram caracterizadas, mostrando percentuais muito similares de celulose e hemicelulose (42,1% e 22,6% para o bagaço e 39,2% e 22,7% para a palha, respectivamente). Isto evidencia potenciais similares de produção de açúcares. Posteriormente, foram realizados experimentos em laboratório para comparar os resultados de rendimento de xilose e produção de furfural após as reações de hidrólise ácida das duas biomassas, com o intuito de verificar se este processo, comumente utilizado para o bagaço, pode ser utilizado para a palha. As variáveis que foram avaliadas foram a concentração de ácido (0,5-3,0%m/m), o tempo reacional (15-60min) e a relação sólido-líquido (RSL - 0,1-0,2m/m). Concentrações de 42,72g/L e de 41,31g/L de xilose foram encontradas para a palha e para o bagaço, respectivamente, alcançando rendimentos de xilose superiores a 80%, em reações em laboratório. Também foram realizados ensaios de hidrólise ácida em planta piloto e de hidrólise enzimática em laboratório para avaliar os resultados de rendimento de glicose da palha. Os resultados de rendimento de xilose e produção de inibidores para estas reações foram avaliados e comparados com os dados obtidos em laboratório. Concentrações de 35,2g/Lde xilose e de 27,3g/L de glicose foram encontradas para a palha, alcançando rendimentos de xilose próximos a 100% e de glicose superiores a 64%, em reações de pré-tratamento em planta piloto e em reações de hidrólise enzimática em laboratório. Os resultados evidenciaram que as variáveis concentração de ácido e relação sólido:líquido são as mais influenciam na produção de xilose e glicose / The growing demand for technologies that produce sustainable biofuels encourages the use of various lignocellulosic materials for this purpose. The aim of this study was to compare the potential production of sugars (glucose and xylose) from sugarcane straw and bagasse. First, the biomasses were characterized, showing very similar percentage of cellulose and hemicellulose (42.1% and 22.6% for the bagasse and 39.2% and 22.7% for the straw, respectively). This is a evidence that the potential of sugar production for bagasse and straw are almost the same. Laboratory experiments were carried out to compare the results of xylose yield and production of furfural after acid hydrolysis reactions for both biomasses in order to determine whether this process, commonly used for bagasse, can be used for straw. The variables that were evaluated were acid concentration (0.5 to 3.0 wt.%), reaction time (15-60min) and liquid-solid ratio (RSL - 0.1-0.2 wt.%). Concentrations of 42.72 g/L to 41.31 g/L of xylose were found to straw and bagasse, respectively, reaching xylose yields higher than 80% in laboratory reactions. Also acid hydrolysis reactions in pilot plant and enzymatic hydrolysis reactions in laboratory were carried out to evaluate the results of straw glucose yields. Also the results of xylose yields and production of inhibitors for these reactions were evaluated and compared to the data obtained in the laboratory. Concentrations of 35.2g/L of xylose and 27.3g/L of glucose were found for straw, reaching xylose yields close to 100% and glucose yields up to 64%, in pretreatment reactions in pilot plant and in enzymatic hydrolysis reactions in the laboratory. It was observed that acid concentration and solid: liquid ratio are the variables that most influence in the results of formation of xylose and glucose