Banca de DEFESA: CAIO SILVA ASSIS FELIX

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : CAIO SILVA ASSIS FELIX
DATA : 31/07/2020
HORA: 08:30
LOCAL: Instituto de Química
TÍTULO:

SYNTHESIS, CHARACTERIZATION AND APPLICATION OF POLYMERS WITH IONS PRINTED FOR QUANTIFICATION OF METALS IN ENVIRONMENTAL SAMPLES

PALAVRAS-CHAVES:

Bismuth, chrome,uranium,ion-imprinted polymers, FAAS, GH-AFS, digital image

PÁGINAS: 150
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Química
SUBÁREA: Química Analítica
ESPECIALIDADE: Análise de Traços e Química Ambiental
RESUMO:

In this work, three new polymers with printed ions (IIP) were synthesized, characterized, optimized and used in pre-concentration systems for the determination of metals in water samples. The IIPs with Bi (III), Cr (III) and U (VI) ions were all synthesized using bulk polymerization and later characterized, with the exception of IIP-U (VI), using infrared spectrometry with Fourier transform (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TG). The materials obtained were used as sorbents in mini-columns, for use in line and batch systems for detection by different spectrometric techniques. One of the systems developed was the IIP-Bi (III). This was applied to an in-line preconcentration system coupled to a hydride generation atomic fluorescence spectrometer (GH-AFS), which initially studied factors that directly influence the ion quantification conditions. In this work, a detection and quantification limit of 26 and 88 ngL-1 was observed, respectively, and a pre-concentration factor of 19.8. The Bi (III) concentrations found in seawater samples ranged from 0.38 ± 0.01 to 0.45 ± 0.01 μg L-1. Another online system was applied to IIP-Cr (III), for determination by flame atomic absorption spectrometry (FAAS) in tap water samples. In summary, a pre-concentration factor of 14, quantification and detection limits of 0.148 mgL-1 and 0.044 mgL-1 were observed. The Cr (III) concentrations found in tap water samples ranged from 0.33 ±0.01 to 0.42 ± 0.01 mgL-1. Finally, a methodology using an IIP-U (VI) as a sorbent was proposed, applying to the method an alternative form of detection, using digital image. The method had detection and quantification limits of 2.55 and 8.51 μg L-1 respectively, and a preconcentration factor of 8.2. Water samples from lakes surrounding the city of Caetité-Ba were analyzed and presented concentrations ranging from 20 to 75 μg L-1.

MEMBROS DA BANCA:
Presidente - 268481 - SERGIO LUIS COSTA FERREIRA
Interno - 1649202 - LEONARDO SENA GOMES TEIXEIRA
Interno - 670.936.635-91 - VALFREDO AZEVEDO LEMOS - UFBA
Interno - 318.201.155-34 - WALTER NEI LOPES DOS SANTOS - UFBA
Externo ao Programa - 3897782 - ICARO THIAGO ANDRADE MOREIRA
Externo ao Programa - 950.990.506-20 - KARINA SANTOS GARCIA - UFF