Banca de QUALIFICAÇÃO: ISABEL DO NASCIMENTO SILVA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : ISABEL DO NASCIMENTO SILVA
DATA : 06/11/2018
HORA: 14:00
LOCAL: Auditório do NUPPRAR
TÍTULO:

STUDY OF THE PHOTOCATALITIC DEGRADATION OF THE CAPTOPRIL DRUGBY THE COMPOSITE OF TiO₂- EXPANDED PERLITE NANOPARTICLES

PALAVRAS-CHAVES:

Captopril. Expanded Perlite. TiO₂. Photocatalytic Degradation

PÁGINAS: 100
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Química
SUBÁREA: Química Analítica
ESPECIALIDADE: Análise de Traços e Química Ambiental
RESUMO:

Concern over the inappropriate disposal of chemicals in the environment has been increasing in recent years. Emerging micropollutants have been causing great impact on nature. Among this class, drugs are highlighted because they are biologically active substances that are difficult to break down by conventional treatment systems. Treatment techniques are required to treat these effluents. The Advanced Oxidative Processes (AOPs) can be used in the treatment of these pollutants, since it is an efficient technique in the mineralization of the contaminant. Among these methods, heterogeneous photocatalysis can be used, being characterized by the use of semiconductors as photocatalysts. The most used semiconductor in this process is TiO₂, presenting good degradation efficiency. However, TiO₂ is easily dispersed, making the separation of the aqueous medium difficult, and must be supported on some material. In this work, expanded perlite (EP), an aluminosilicate of volcanic origin, was used as a support material, thus obtaining a composite. The study was carried out with captopril (CAP), an antihypertensive, also characterized as teratogenic substance, and can cause several damages in fetuses. The synthesis of the composites was based on the methodology described in the literature. Initially tests were carried out to verify the adsorption equilibrium, in which 200 mL of CAP solution in 100 mg of composite was used in a photocatalytic reactor, without radiation. For the photocatalytic tests, the same conditions were maintained, but a 9 watt lamp was used in the irradiation process, and the same parameters were established for the photolysis tests without the use of the composite. The results show that the characterization techniques used in this study, FTIR, XRD, FRX, SEM, EDS and particle size analysis, showed that the TiO₂ was incorporated in the EP matrix. The adsorption/ desorption experiments showed that the adsorption equilibrium time for the composites in the CAP drug solution was 30 minutes. The photolysis and photocatalysis tests indicated that the main effect between the two degradation methods is in relation to the time of analysis. There was degradation of 32.0% in 285 minutes for photocatalysis and 26.5% in the time of 450 minutes for photolysis, at the concentration of 50 mg L^-1. The percentages of degradation at the concentrations of 50, 40, 30, 20 and 10 mg L^-1 were respectively for photolysis 26.5; 26.3; 26.1; 40.0 and 43.1% and for photocatalysis at the concentrations of 50, 40, 30 and 20 mg L^-1 were 32.0; 36.0; 38.3 and 41.0%. Degradation to the composites T-PE-0.3 and T-PE-0.1 show that there was a reduction in the concentration of CAP of 18.5% for the T-PE-0.3 composite at the concentration of 50 mg L^-1 at 120 minutes and 33.7% at 10 mg L^-1 at 90 minutes. For the T-PE-0.1 composite, there was a degradation of 26.3% in 240 minutes for the concentration of 50 mg L^-1 and 32.7% for the concentration of 10 mg L^-1 in the time of 120 minutes. The kinetic study showed that kinetics is governed by the Langmuir-Heinshelwood model. The kinetics of the system was obtained as being of first order. The toxicity tests showed that CAP had a negative influence on the germination and growth of Lactuca sativa seeds, but the treated effluents showed a similar performance to the positive control. The energy cost study showed that the process is economically viable, indicating a minimum value of R$ 0.1503 for the concentrations of 40 and 30 mg L^-1 in the degradation of CAP by photolysis.

MEMBROS DA BANCA:
Interno - 1645110 - CARLOS ALBERTO MARTINEZ HUITLE
Interno - 348475 - DJALMA RIBEIRO DA SILVA
Presidente - 1412709 - NEDJA SUELY FERNANDES