Banca de DEFESA: JOSÉ ADOLFO OLIVEIRA DAS CHAGAS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : JOSÉ ADOLFO OLIVEIRA DAS CHAGAS
DATA : 25/01/2017
HORA: 08:30
LOCAL: Auditório do NUPPRAR
TÍTULO:

CHITOSAN MEMBRANES WITH GLYCEROL FOR APPLICATION IN WASTEWATER TREATMENT

PALAVRAS-CHAVES:

Chitosan. Glycerol. Sorption. Copper

PÁGINAS: 80
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Química
SUBÁREA: Química Orgânica
ESPECIALIDADE: Polímeros e Colóides
RESUMO:

Over the past 20 years, the amount and composition of wastewater from oil exploration and processing activities has raised concerns about environmental risks. Methods, such as filtration, reverse osmosis, adsorption and chemical oxidation are commonly applied in the treatment of these waters. However, these methods may present limitations, such as, energy cost, space for installation, by-products generation, among others. Considering that, biopolymer based membranes appear as an alternative and low cost material. Within this class, chitosan, a polycationic polysaccharide obtained from chitin, has been investigated. The present work aimed to investigate the effects of the addition of glycerol on the properties of chitosan membranes and to evaluate its applicability on wastewater treatment. The membranes were obtained by casting and the glycerol was added to the chitosan powder in two ratios (w / w): 10% and 25%. Glycerol membranes were named CS10 and CS25, respectively. The membranes CS, CS10 and CS25 were characterized by infrared absorption spectroscopy (FTIR), X-ray diffraction (XRD), Atomic Force Microscopy (AFM), thermal analysis (TG / DSC).  Swelling index, mechanical properties, and copper adsorption capacity were also analyzed. Comparing the infrared spectra it was possible to confirm the glycerol incorporation. This fact was also confirmed by XRD and AFM. From the XRD, an increase in the percentage of crystallinity for CS10 was observed, while in CS25 a reduction occurred. AFM topology studies also corroborate these effects. The presence of glycerol also affects the mechanical properties of chitosan. While CS25 has higher ductility, CS10 is more rigid. The swelling index values for the membranes CS10 and CS25 at pH 6 showed that the presence of glycerol gives a higher hydrophilic character to the membranes. CS25 membrane showed a reduction in swelling indexes at pH 4 and pH 10, while CS10 had the swelling indexes favored in these media. In the adsorption studies, excellent adsorption properties were found, reaching values between 0.17-0.22 g.m^-2, and the CS25 membrane was more efficient for the removal of copper. Therefore, from this study it was possible to consider that the material has potentiality for the application in the wastewater treatment of the petroleum industry.

MEMBROS DA BANCA:
Interno - 1530500 - ANA CRISTINA FACUNDO DE BRITO PONTES
Externo à Instituição - MARCELO SILVEIRA RABELLO - UFCG
Presidente - 2203888 - MARCIA RODRIGUES PEREIRA