Banca de QUALIFICAÇÃO: RUTHINEIA JESSICA ALVES DO NASCIMENTO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : RUTHINEIA JESSICA ALVES DO NASCIMENTO
DATA : 10/06/2016
HORA: 14:00
LOCAL: AUDITÓRIO DO PPGEQ
TÍTULO:

Real-time monitoring of enzymatic hydrolysis of coconut coir by near infrared spectroscopy (NIRS)

PALAVRAS-CHAVES:

monitoring, NIRS, enzymatic hydrolysis, second generation ethanol

PÁGINAS: 128
GRANDE ÁREA: Engenharias
ÁREA: Engenharia Química
RESUMO:

This study, in a first step, investigates the application of near infrared spectroscopy for rapid qualitative characterization of coconut coir and evaluates the potential of this lignocellulosic material for the production of second-generation ethanol. In a second step, the near infrared spectroscopy coupled with data mathematical pretreatment methods and multivariate calibration methods was investigated to evaluate its potential for real-time monitoring of the enzymatic hydrolysis process of coconut husk. The residue of coconut husk was subjected to four types of physico-chemical pretreatments: Pre-treatment with dilute sulfuric acid (2% w/v), pre-treatment with dilute sulfuric acid (0.2% w/v ), alkaline pre-treatment (0.5% w/v) and hydrothermal pre-treatment. The morphological variations, chemical composition and crystallinity index caused by the physical-chemical pre-treatments were evaluated. We also investigated the influence of pretreatments in yields of enzymatic hydrolysis and the yield of theoretical ethanol for this process. Changes in lignin, hemicellulose and crystalline cellulose were characterized by traditional methods such as SEM and XRD and using an alternative analytical method using NIR spectroscopy and good results were obtained. Pretreatment with dilute phosphoric acid proved to be more efficient when the production of bioethanol is aimed, resulting in 39.16% yield of enzymatic hydrolysis and 83.68 L/t for theoretical ethanol yield. The calibration models for monitoring were built and optimized using the cross-validation process and the predictive ability of these methods were analyzed by the external validation process. The mathematical pretreatment performed on spectral data were SNV + 1st derivative, SNV + 2nd derivative, MSC + 1st derivative, MSC + 2nd derivative, SMA + 1st derivative and SMA + 2nd derivative. The best calibration models for quantification of ART, glucose, cellulose conversion and theoretical ethanol yield were obtained for the mathematical pretreatment SMA + 2nd derivative. The obtained calibration models were used for monitoring an enzymatic hydrolysis process of coconut coir with satisfactory results for the monitoring of enzymatic hydrolysis step of second generation ethanol manufacturing process.

MEMBROS DA BANCA:
Externo ao Programa - 1584174 - DOMINGOS FABIANO DE SANTANA SOUZA
Interno - 1346198 - EVERALDO SILVINO DOS SANTOS
Presidente - 347401 - GORETE RIBEIRO DE MACEDO
Interno - 1547970 - JACKSON ARAUJO DE OLIVEIRA