Banca de DEFESA: SUEILHA FERREIRA DE ANDRADE DE PAULA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : SUEILHA FERREIRA DE ANDRADE DE PAULA
DATE: 30/01/2023
TIME: 09:00
LOCAL: videoconferência
TITLE:

PYROLYSIS- GC/MS OF SPIRULINA PLATENSIS: EVALUATION OF BIOMASSES GROWN UNDER AUTOTROPHIC AND MIXOTROPHIC CONDITIONS.

KEY WORDS:

Mixotrophic, Spirulina platensis, Biomass, Volatile compounds, Pyrolysis.

PAGES: 136
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Orgânica
SPECIALTY: Química dos Produtos Naturais
SUMMARY:

Microalgae are autotrophic microorganisms that fix CO2 with great potential to produce biofuels in a sustainable way, but the bottleneck is the high cost of obtaining biomass. Mixotrophic growth has been presented as an alternative to achieve economic and environmental sustainability. The biomass used in this work comes from autotrophic and mixotrophic cultivation of S. platensis grown respectively in control medium (Zarrouk) and with the addition of cheese whey at different concentrations, 2.5 (M2.5), 5.0 (M5) and 10.0% (M10), and was provided by Pereira [19] to carry out the characterization of biomasses through Elementary Analysis and calorific value. In addition, their thermal stability was evaluated using thermal analysis through thermogravimetry and fast micropyrolysis (Py-CG/MS) at temperatures of 450 °C, 550 C°C and 650 °C in the evaluation of the production of volatile compounds. The pyrolysis of the biomasses obtained in the autotrophic and mixotrophic cultures, was carried out with the purpose of obtaining bio-oil and valuable chemical products. Due to the influence of the culture medium, the biomasses used in this study present different biochemical compositions and this was observed in the obtained results of calorific value, TGA and volatile compounds evaluated by Py-GC/MS at 450°C, 550°C and 650°C. From the results obtained by thermogravimetry, it was possible to observe that the mass loss processes of all the biomasses in our study occurred in a similar way. As for pyrolysis, we had that the M10 sample, due to its lower protein content, formed a smaller amount of nitrogenous compounds by pyrolysis at all evaluated temperatures. There was a reduction of 43.8% (450º), 45.6% (550ºC) and 23.8% (650ºC) in the formation of nitrogenous compounds in relation to sample A. In addition, the temperature also showed a considerable effect on the formation of volatile compounds. The highest yields of nitrogenous compounds, phenols and aromatic and non-aromatic hydrocarbons were observed at 650ºC. Oxygenated and N and O-containing compounds decreased with increasing temperature. Hydrocarbons such as toluene, heptadecane and heneicosan were produced by pyrolysis of S. platensis. Therefore, these biomasses used in this study proved to be attractive for the production of high quality bio-oil and valuable chemicals, requiring an update regarding the content of nitrogenous compounds, through manipulation of growth conditions and process temperature of pyrolysis.

COMMITTEE MEMBERS:
Externa à Instituição - CRISTIANE FRANCISCA DA COSTA SASSI - UFPB
Externo à Instituição - JANDUIR EGITO DA SILVA - IFRN
Externa ao Programa - 7350310 - MARIA DE FATIMA VITORIA DE MOURA - nullInterna - 2413537 - POLLYANA SOUZA CASTRO
Presidente - 1569526 - RENATA MENDONÇA ARAUJO