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| Author(s): |
Olavo Micali Perrone
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São José do Rio Preto. 2019-10-02. |
| Institution: | Universidade Estadual Paulista (Unesp). Instituto de Biociências Letras e Ciências Exatas. São José do Rio Preto |
| Defense date: | 2019-09-19 |
| Advisor: | Mauricio Boscolo |
| Abstract | |
Increasing the value of ethanol and sugarcane biomass by reactions catalyzed by oxides is presented in this work. The oxides used are derived from hydrotalcites, whose general formula is: Mg6Al2 (CO3)(OH)16·4(H2O), modified by Ag, Cu, Fe, La, Nb, Ni, In or Pd. The catalysts synthesized were characterized by their surface area the number of acid and basic catalytic sites, X-ray diffraction and infrared spectroscopy. The conversion of ethanol into products of higher molecular weight and with added value, mainly through the Guerbet reaction, was performed in reactions in supercritical state using stainless steel reactors and oxides as catalysts. The products were analyzed by gas chromatography (GC-FID and GC-MS) and the results were compared with the available characterization data of the material and previous studies in the scientific literature. Oxide modification by each different ion showed a different reaction profile and different products. Lanthanum addition showed better results using anhydrous alcohol and a significant amount of C6 compounds, such as hexanol (42% selectivity), were obtained. On the other hand, the best yields (~30%) for butanol were obtained with the oxide modified by niobium, while the addition of silver led to the reduction of the catalytic activity of the oxide. The addition of biomass into a supercritical ethanol reaction showed that the lignocellulosic material can be deconstructed, phenolic, and furanic compounds from lignin and carbohydrates, respectively can be produced. The presence of hydrogen in the reaction medium promotes successive hydrogenations in the aromatic compounds, leading to the opening of the ring or the formation of cyclohexane. Modifications using indium and palladium ions allow butanol to be obtained at low temperatures and with good selectivity (-65%) and low co-product formation. Finally, zirconium, cerium and niobium oxides had high selectivity (~95%) for diethyl carbonate during its synthesis from ethanol and CO2. (AU) | |
| FAPESP's process: | 15/11588-4 - Hydrotalcites containing Ag, Cu, Ni, Fe, La or Nb as catalysts for dehydrogenation of ethanol and hydrogenation of sugar cane bagasse |
| Grantee: | Olavo Micali Perrone |
| Support Opportunities: | Scholarships in Brazil - Doctorate |