Banca de DEFESA: HENRIQUE GIÁCOMO PEREIRA MENEZES

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : HENRIQUE GIÁCOMO PEREIRA MENEZES
DATE: 06/10/2022
TIME: 14:00
LOCAL: Auditório - Campus Gameleira
TITLE:

Trapping of polycyclic aromatic hydrocarbons from heavy-duty vehicles emissions using IT-FEX in tube device and analysis by gas chromatography

KEY WORDS:

PAH; heavy-duty vehicles emissions; IT-FEX; method validation

PAGES: 96
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Analítica
SPECIALTY: Análise de Traços e Química Ambiental
SUMMARY:

The high demand in the delivery of domestic and industrial supplies has caused a significant increase in the amount of cargo vehicles in transit in Brazil, with the road modal as the main one in the transportation of goods and supplies in the national territory. These vehicles, for using mostly diesel oil as fuel, are responsible for a significant emission of volatile organic compounds (VOCs) into the atmosphere, especially a class called polycyclic aromatic hydrocarbons (PAHs), known for their high carcinogenicity. In order to detect and quantify the PAHs from vehicle emissions of this class, we used a standard reference chemical mixture (SQR) of 15 PAHs (from one to six aromatic rings) and developed an analytical method for gas chromatography instrumentation coupled to a dielectric barrier discharge ionization detector (GC/BID), using the IT-FEx polydimethylsiloxane (PDMS) polymer-phase-coated in-tube extraction device. The fabricated devices were subjected to physicochemical characterizations using Thermogravimetric Analysis (TG) and Absorption Spectroscopy in the Infrared (IR) region. The thickness of the polymeric film was evaluated by electronic miscroscopy with a digital camera (10x magnification), resulting in approximately 29 μm. The interaction of the PAHs with the IT-FEx polymeric phase was evaluated, both in aqueous medium (equilibrium kinetics) and in gaseous medium (dynamic phase), being the equilibrium time (aqueous) equal to 25 min and the dynamic analysis (gaseous) equal to 30 s. A better interaction was observed between medium-sized PAHs with PDMS (four aromatic rings) compared to smaller (one to three rings) and larger ones (five to six rings), in both phases (aqueous and gaseous). Emissions from two diesel-powered heavy-duty vehicles (2006 - P5 and 2012 - P7) were evaluated using the IT-FEx coupled to a vehicular sampler (trapping of VOCs by the PDMS film) and analyzing them by GC/BID and GCxGC/FID, which made it possible to observe the difference in the pollutant profile from each emission (mainly through the 3D visualization of the chromatograms referring to the analysis in the GCxGC/FID), with the 2006 vehicle having a greater amount of VOCs detected compared to the 2012. The presence of PAHs was also detected for both (according to their respective retention times compared to those obtained by the standard PAHs solution), being phenanthrene, fluoranthene, benzo[a]anthracene and chrysene for the 2006, and benzo[a]anthracene, chrysene, benzo[b]fluoranthene, and benzo[k]fluoranthene for the 2012.

BANKING MEMBERS:
Presidente - PATRICIA SUELI DE REZENDE
Interna - ADRIANA AKEMI OKUMA
Externo ao Programa - CLEVERSON FERNANDO GARCIA
Externa ao Programa - JANICE CARDOSO PEREIRA ROCHA
Externo ao Programa - PATTERSON PATRICIO DE SOUZA