Banca de QUALIFICAÇÃO: JOSÉ ADOLFO OLIVEIRA DAS CHAGAS

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : JOSÉ ADOLFO OLIVEIRA DAS CHAGAS
DATA : 02/12/2016
HORA: 08:30
LOCAL: sala 3F1
TÍTULO:

PREPARATION AND CHARACTERIZATION OF CHITOSAN MEMBRANES WITH GLYCEROL FOR APPLICATION IN WASTEWATER TREATMENT

PALAVRAS-CHAVES:

Chitosan. Glycerol. Sorption. Copper

PÁGINAS: 75
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, generation of by-products, among others. In view of this, 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 aims to investigate the effects of the addition of glycerol on the properties of chitosan membranes and to evaluate its applicability in the treatment of wastewater. The membranes were obtained by casting and the glycerol was added to the chitosan powder in two proportions (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) analysis, Atomic Force Microscopy (AFM) analysis, swelling index determination, Mechanical properties, thermal analysis (TG / DSC) and adsorption of copper ions. From the comparative analysis of the infrared spectra it was possible to confirm the incorporation of the glycerol. This fact is also confirmed by the techniques of XRD and AFM. From the XRD, an increase in the percentage of crystallinity for CS10 was observed, while in CS25 the reduction occurred. AFM topology studies also indicate these effects. The presence of glycerol also directly affects the mechanical properties of chitosan. The results show that CS25 has higher ductility, while CS10 is more rigid. The swelling index values for the membranes CS10 and CS25 in neutral medium show that the presence of glycerol gives a higher hydrophilic character to the membranes. The 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 0.17-0.20 g.m-2, and the CS25 membrane was more efficient for the removal of copper. Therefore, from this study it is possible to consider that the material has potential for the application in the wastewater treatment of the petroleum industry.

MEMBROS DA BANCA:
Interno - 1530500 - ANA CRISTINA FACUNDO DE BRITO PONTES
Presidente - 2203888 - MARCIA RODRIGUES PEREIRA
Interno - 1149440 - ROSANGELA DE CARVALHO BALABAN