Modelo cinético da produção de acetona-butanol-etanol co-utilizando açúcares mistos e furaldeídos da biorrefinaria de cana-de-açúcar por Clostridium saccharoperbutilacetonicum N1-4
Data
2024-09-30
Autores
Oliveira, Roger Assis de 
Orientadores
Tovar, Laura Plazas
Tipo
Dissertação de mestrado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
O biobutanol é considerado um combustível alternativo promissor para substituir o diesel e a gasolina. A produção de butanol é comumente realizada através da fermentação ABE, onde um substrato é convertido em uma mistura de etanol, butanol e acetona pela ação de bactérias do gênero Clostridium spp. Embora o processo seja promissor, ele é caracterizado por baixa eficiência e produtividade. O alto custo da matéria-prima de primeira geração, contribui significativamente para o custo elevado do processo. Assim, é necessário investigar a utilização de matérias-primas de menor custo, como os resíduos agroindustriais da biorrefinaria de cana-de-açúcar. Este trabalho propôs um modelo cinético dinâmico para investigar os efeitos dos açúcares mistos presentes no hidrolisado hemicelulósico e no melaço da cana-de-açúcar, além dos furaldeídos (furfural e HMF) formados durante a hidrólise da hemicelulose, na produção de ABE por C. saccharoperbutylacetonicum N1-4. A análise de sensibilidade de modelos na literatura e do próprio modelo revelou que as reações associadas à produção e consumo de acetil-CoA e butiril-CoA estão relacionadas ao aumento do rendimento de butanol. Os parâmetros cinéticos do modelo foram estimados por métodos determinísticos em uma rotina computacional desenvolvida no Scilab®. Os resultados mostraram que, apesar da forte preferência do microrganismo por açúcares hexoses, a inclusão de até 25% de pentoses não está associada a uma redução significativa na produção de butanol. Além disso, a presença dos furaldeídos perturba principalmente a assimilação dos ácidos acético e butírico e a produção de acetil-CoA e butiril-CoA, atuando como potenciais estimulantes para a produção de solventes. O Modelo infere que a utilização de resíduos agroindustriais como matéria-prima pode tornar o processo de produção de biobutanol mais eficiente e economicamente viável.
Biobutanol is regarded as a promising alternative fuel that can complement diesel and gasoline. Butanol is commonly produced through ABE fermentation, where a substrate is converted into a mixture of ethanol, butanol, and acetone by bacteria of the genus Clostridium spp. Although this process is promising, it is characterized by low efficiency and low productivity. The high cost of raw materials, especially firstgeneration materials, contributes significantly to the high cost of the process. Therefore, it is necessary to investigate the use of secondgeneration raw materials, particularly agroindustrial wastes from sugarcane biorefineries. This work proposed a dynamic kinetic model to investigate the effects of mixed sugars present in hemicellulosic hydrolysate and sugarcane molasses, as well as furans (furfural and HMF) formed during hemicellulose hydrolysis, on ABE production by C. saccharoperbutylacetonicum N14. Sensitivity analysis of models in the literature and the proposed model revealed that reactions associated with the production and consumption of acetylCoA and butyrylCoA are related to increased butanol yield. The kinetic parameters of the model were estimated using a deterministic method in a Scilab® routine. The results showed that, despite the microorganism's strong preference for hexose sugars, the inclusion of up to 25% pentoses is not associated with a significant reduction in butanol production. Additionally, the presence of furans mainly disrupts the assimilation of acetic and butyric acids and the production of acetylCoA and butyrylCoA, acting as potential stimulants for solvent production. The model infers that the use of agroindustrial waste as raw material can make the biobutanol production process more efficient and economically viable
Biobutanol is regarded as a promising alternative fuel that can complement diesel and gasoline. Butanol is commonly produced through ABE fermentation, where a substrate is converted into a mixture of ethanol, butanol, and acetone by bacteria of the genus Clostridium spp. Although this process is promising, it is characterized by low efficiency and low productivity. The high cost of raw materials, especially firstgeneration materials, contributes significantly to the high cost of the process. Therefore, it is necessary to investigate the use of secondgeneration raw materials, particularly agroindustrial wastes from sugarcane biorefineries. This work proposed a dynamic kinetic model to investigate the effects of mixed sugars present in hemicellulosic hydrolysate and sugarcane molasses, as well as furans (furfural and HMF) formed during hemicellulose hydrolysis, on ABE production by C. saccharoperbutylacetonicum N14. Sensitivity analysis of models in the literature and the proposed model revealed that reactions associated with the production and consumption of acetylCoA and butyrylCoA are related to increased butanol yield. The kinetic parameters of the model were estimated using a deterministic method in a Scilab® routine. The results showed that, despite the microorganism's strong preference for hexose sugars, the inclusion of up to 25% pentoses is not associated with a significant reduction in butanol production. Additionally, the presence of furans mainly disrupts the assimilation of acetic and butyric acids and the production of acetylCoA and butyrylCoA, acting as potential stimulants for solvent production. The model infers that the use of agroindustrial waste as raw material can make the biobutanol production process more efficient and economically viable