Banca de DEFESA: ISABEL DO NASCIMENTO SILVA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : ISABEL DO NASCIMENTO SILVA
DATA : 23/07/2019
HORA: 14:00
LOCAL: Auditório do NUPPRAR
TÍTULO:

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

PALAVRAS-CHAVES:

Captopril. Expanded Perlite. TiO₂. Photocatalytic degradation. Waste treatment

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 substances 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. The Advanced Oxidative Processes (AOPs) can be used in the treatment of these pollutants, because 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 can be easily dispersed making the aqueous medium separation process difficult, and needs to be supported on some material. In this work, expanded perlite (EP), an aluminosilicate of volcanic origin, was used as 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, however, using a 9 and 18 Watt lamps in the irradiation process, the same parameters being established for the photolysis tests without the use of the composite. The results show that the characterization techniques used in this study, IV, XRD, FRX, SEM, EDS and particle size analysis, showed that the TiO₂ was incorporated in the EP matrix. The adsorption / desorption tests 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, 20 and 10 mg L^-1 were 32.0, 36.0, 38.3, 41.0% and 42.8%. Degradation to T-EP-30% and T-EP-10% composites showed that there was a reduction in the concentration of CAP of 18.5% for the T-EP-30% composite at 50 mg L^-1 concentration in the time of 120 minutes and 33.7% for the concentration of 10 mg L^-1 in the time of 90 minutes. For the T-EP-10% 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, indicating that the composite with higher TiO₂ content was more effective in the degradation. 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 the CAP had a negative influence on the germination and growth of the Lactuca sativa seeds, but the treated effluents showed a similar performance to the positive control. The increase of the radiation intensity favors the degradation process, presenting better results for the composite T-EP-50% in the concentration of 10 mg L^-1. The TOC analysis showed that the test with the concentration of 10 mg L^-1 of CAP and with the composite T-EP-50% with power of radiation of 18 W had a better percentage of effluent mineralization, 39.8%. The energy cost study showed that the most economical process was for photocatalysis in the concentration of CAP of 10 mg L^-1 in the power of radiation of 18 W and for the photolysis process in the concentration of CAP of 10 mg L^-1 in the values of R $ 0.057 and 0.0962, respectively.

MEMBROS DA BANCA:
Externa à Instituição - CLÁUDIA DE OLIVEIRA CUNHA - UFPB
Interno - 348475 - DJALMA RIBEIRO DA SILVA
Externa ao Programa - 2275848 - ELISAMA VIEIRA DOS SANTOS
Externa à Instituição - LIDIANE ALVES DE MORAIS - UFERSA
Presidente - 1412709 - NEDJA SUELY FERNANDES