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Master of Science / Department of Chemical Engineering / Keith Hohn / Acid catalysts have been shown to be very successful in the pretreatment of cellulosic biomass to improve glucose yield and improve overall yield of ethanol. This report presents the results of a techno-economic study that looks into the use of nanoscale magnetic solid acid catalysts for glucose production. Magnetic solid acid catalysts are an improvement over using diluted acid due to eliminating acid-waste generation and corrosion hazards. Their magnetic nature also allows them to be easily separated from reaction products by an external magnetic force. After the technology is analyzed, a series of unit operations is proposed to go from the laboratory scale to the industrial plant scale. The next step was to develop material and energy balances using HYSYS process simulation software. Capital and operating costs are estimated and all the information is combined into a discounted cash flow economic model. The economic portion of the report uses a probabilistic cost assessment. It is used to quantify the range of risks in the project from swings in feedstock costs, differences in yield from catalysts, and any other significant variables. Both capital costs (initial equipment & construction investment) and operating costs (feedstock supply, chemicals, and personnell) are included with ranges of error based on databases and expert opinion. This method of evaluating investment efficiency can be helpful for predicting the cost benefits of proposed future research. The yield and percent catalyst magnetically recovered is assumed based on laboratory research to simplify the model. A 2000 metric tons of biomass per day facility was analyzed. Using the magnetic solid acid catalyst technology, the capital costs are estimated to be $160 million and this technology saves around 10% of capital costs compared to ethanol plants that uses conventional acid hydrolysis. The yield of the magnetic solid acid catalysts should be around 75% to compete with existing ethanol technologies. The metric used for this report is the discount profitability index (DPI) which is the ratio of future cash flows divided by investment. A DPI “hurdle rate” of 1.3 is used, which is similar to industry economic metrics of projects that include new process plants. The calculated DPI for the project is 1.38 DPI which is higher than using conventional cellulose treatment technologies. The recommendation is continue to study this technology’s large scale applicability before attempting any plant pilot studies.

Made available in DSpace on 2017-07-10T15:14:40Z (GMT). No. of bitstreams: 1 Glaucio_J_Gomes.pdf: 2760994 bytes, checksum: ed1586b3de70d1981cd1f4c6b68eb593 (MD5) Previous issue date: 2016-04-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The application of zeolites in catalytic processes is of great interest in several chemical reactions that involves transformation of biomass into higher value-added products. In a similar sense, conversion of fatty acids into esters catalyzed by Hzeolites have sprouted a widely-varied academic and industrial attention due to it providing a sustainable route inside the Green Chemistry for the production of chemicals and energy, of interest in biodiesel synthesis. Thermogravimetric analysis (TGA-IR), FTIR and FTIR-ATR spectroscopy, and theoretical studies [DFT method at M06-2X/6-31G(D) level] as support of experimental data are employed to investigate the adsorption of methanol and acetic acid as reaction models of fatty acids on the surface of H-Beta and H-ZSM-5 zeolites. The results obtained by TGA-IR for adsorption of acetic acid and methanol in both zeolites show different processes of mass loss that correlated with the adsorption mode (physical and chemical adsorption). The spectra obtained by FTIR-ATR show that acetic acid is molecularly adsorbed on H-Beta through the carbonyl group on the Brønsted site and, by the hydroxyl group on the Lewis site, the experimental evidence is supported by the theoretical vibrational analysis. The acetic acid adsorption by C=O on the Brønsted site is more stable than other proposals of adsorption found in the literature. For HZSM- 5 zeolite, FTIR-ATR spectrum reported changes in the structural composition of the material, therefore it was not possible to compare theoretical and experimental results. Moreover, different models of adsorption/co-adsorption of acetic acid and methanol on the surface of H-zeolites have been studied by theoretical calculations in order to provide information that could be helpful in the interpretation of the first step of the mechanism of acetic acid esterification with methanol on H-Beta and HZSM- 5 zeolites. / A aplicação de zeólitas em processos catalíticos é de grande interesse em inúmeras reações químicas para transformação de biomassa em produtos de maior valor agregado. Neste sentido a conversão de ácidos graxos em ésteres catalisadas por H-zeólitas recentemente ganha grande atenção na academia e na indústria uma vez que fornece uma rota sustentável dentro da Química Verde destinada à produção de produtos químicos e energia, de interesse na produção de biodiesel. Assim, a reação de esterificação por catálise heterogênea é complexa envolvendo inúmeros passos reacionais na superfície que podem ocorrer simultaneamente sendo de interesse também compreender os passos elementares envolvidos nesta reação. Nesta dissertação buscou-se compreender o processo de adsorção de metanol e ácido acético como modelos de reação para ácidos graxos sobre a superfície da zeólita H-Beta e H-ZSM-5 por termogravimetria (TGA-IV), espectroscopia (FTIR e FTIR-ATR) e a aplicação de estudos teóricos [cálculos DFT a nível M06-2X/6- 31G(D)] como suporte aos dados experimentais. Os resultados encontrados para ambas as zeólitas por TGA-IV permitiram estudar a adsorção de ácido acético e metanol, sendo identificados diferentes processos de perda de massa correlacionados com a forma de adsorção (adsorção física e química). Os espectros obtidos por FTIR-ATR nos indicaram que o ácido acético se encontra molecularmente adsorvido sobre H-Beta, a partir do grupo carbonila com os sítios de Brønsted e o grupo hidroxila com o sítio de Lewis, é comprovada pelas frequências vibracionais do modelo teórico. A adsorção de ácido acético por C=O sobre o sítio de Brønsted é mais estável que outras propostas encontradas na literatura. Para a zeólita H-ZSM-5 os espectros de FTIR-ATR informaram alterações na composição estrutural do material o qual não foi possível realizar comparações com estudo teórico. Por outro lado os cálculos teóricos puderam prever diferentes modelos de adsorção/co-adsorção de ácido acético e metanol sobre a superfície de H-zeólitas a fim de proporcionar informações que podem auxiliar a interpretação do primeiro passo da reação de esterificação ácido acético e metanol em H-Beta e H-ZSM-5.