Banca de QUALIFICAÇÃO: PEDRO FELYPE FERREIRA ARAUJO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : PEDRO FELYPE FERREIRA ARAUJO
DATE: 28/02/2024
TIME: 14:00
LOCAL: videoconferência
TITLE:

Synthesis and application of silver nanoparticles (AgNPs) for quantification of scale inhibitors and scale cations in the petroleum industry.

KEY WORDS:

silver nanoparticle; fouling; scale inhibitor; optical nanosensor; colorimetric detection

PAGES: 50
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Orgânica
SPECIALTY: Polímeros e Colóides
SUMMARY:

The search for alternative analytical methods for determining scale inhibitors and scale cations has aroused interest in the petroleum industry. In this sense, silver nanoparticles (AgNPs), more specifically the optical properties of Localized Surface Plasmon Resonance (LSPR), become a promising material for the development of nanoplatforms for spectral optimization and nanosensors. optics. Thus, the objective of this work was to combine AgNPs with Raman spectroscopy (SERS), UV-Vis spectroscopy and digital images (using a smartphone and free software, Image J) to determine the concentration of scale inhibitors (ATMP and DTPMP) and fouling cations (Mg+2, Ca+2, Sr+2 and Ba+2). These methodologies were based, respectively, on the properties of AgNPs for Raman signal amplification, variation in the absorbance intensity of the plasmonic band (400 nm) and changes in the color of the silver nanoparticle solution in the presence of the analyte. The SERS effect allowed the detection of ATMP in concentrations in the order of 10-4 M. Furthermore, digital imaging and UV-Vis spectroscopy analyzes quantified fouling cations and the inhibitor DTPMP in concentrations in the order of 10-6 M, with excellent linear regression. Characterizations by UV-Vis spectroscopy and Dynamic Light Scattering (DLS) proved that the sensor is based on the mechanism of aggregation or stabilization of AgNPs, depending on the analyte with which they interact. Thus, the results obtained demonstrated that the methodologies developed are efficient, reliable, low-cost and less laborious, when compared to traditionally used methodologies (volumetry and ICP-OES).

COMMITTEE MEMBERS:
Externo à Instituição - MAXWELL GOMES DA SILVA - UFRN
Interno - 1859346 - MIGUEL ANGELO FONSECA DE SOUZA
Externo à Instituição - RAFAEL DA SILVA FERNANDES - UFRN
Presidente - 1149440 - ROSANGELA DE CARVALHO BALABAN