Título: | DETERMINATION OF AS AND MN IN DIESEL, GASOLINE E NAPHTHA BY GF AAS AND OF CU, FE, NI AND V IN PETROLEUM USING SS-GF AAS | ||||||||||||||||||||||||||||||||
Autor: |
GEISAMANDA PEDRINI BRANDAO |
||||||||||||||||||||||||||||||||
Colaborador(es): |
REINALDO CALIXTO DE CAMPOS - Orientador EUSTAQUIO VINICIUS RIBEIRO DE CASTRO - Coorientador HONERIO COUTINHO DE JESUS - Coorientador |
||||||||||||||||||||||||||||||||
Catalogação: | 01/ABR/2008 | Língua(s): | PORTUGUESE - BRAZIL |
||||||||||||||||||||||||||||||
Tipo: | TEXT | Subtipo: | THESIS | ||||||||||||||||||||||||||||||
Notas: |
[pt] Todos os dados constantes dos documentos são de inteira responsabilidade de seus autores. Os dados utilizados nas descrições dos documentos estão em conformidade com os sistemas da administração da PUC-Rio. [en] All data contained in the documents are the sole responsibility of the authors. The data used in the descriptions of the documents are in conformity with the systems of the administration of PUC-Rio. |
||||||||||||||||||||||||||||||||
Referência(s): |
[pt] https://www.maxwell.vrac.puc-rio.br/projetosEspeciais/ETDs/consultas/conteudo.php?strSecao=resultado&nrSeq=11501&idi=1 [en] https://www.maxwell.vrac.puc-rio.br/projetosEspeciais/ETDs/consultas/conteudo.php?strSecao=resultado&nrSeq=11501&idi=2 |
||||||||||||||||||||||||||||||||
DOI: | https://doi.org/10.17771/PUCRio.acad.11501 | ||||||||||||||||||||||||||||||||
Resumo: | |||||||||||||||||||||||||||||||||
Petroleum is a complex mixture of hydrocarbons (50 to 95 percent)
and nonhydrocarbons
(mainly S, N, O and heavy metal compounds). Metallic traces
are
normally found in petroleum as naturally occurring elements
associated to the
formation process. Although present only in small amounts
(Microgram −1 or ng g−1
levels), their determination is of great interest because
of their high potential of
environmental contamination and interference in the
refining process. They may
corrode refinery equipment, poison and foul catalysts
and/or cause undesirable
side reactions in refinery operations. Moreover, heavy
metals present in petroleum
derivates such as diesel, gasoline and naphtha are related
to poor performance and
reduction of their thermal stability. Thus, fast, simple
and reliable procedures for
the determination of trace metals in petroleum and its
derivates by graphite
furnace atomic absorption spectrometry were studied. For
diesel, gasoline and
naphtha samples, procedures for the determination of As and
Mn (ng mL−1 levels)
are proposed. Sample stabilization was necessary and
achieved by the formation
of three component system prepared by mixing appropriate
volumes of the
samples, propan-1-ol and nitric acid aqueous solution,
resulting in a one-phase
medium indefinitely stable (microemulsion). The use of
matrix modification was
also investigated. Multivariate optimization defined the
optimum microemulsion
composition as well as the temperature program. The limits
of detection in the
original samples for As were 1.8, 1.2 and 1.5 ng ml−1 while
for Mn they were 0.6,
0.5 and 0.3 ng mL-1 for diesel, gasoline and naphtha,
respectively. Methods
accuracies were confirmed by recoveries tests and the
analysis of a set of
commercial samples by the proposed and independent
comparative procedures.
For petroleum samples, procedures for the direct
determination of Ni, Cu, Fe and
V using a solid sampling accessory, without any sample pre-
treatment, are
proposed. A Pd+Triton X-100 solution was used as chemical
modifier. The pyrolysis and atomization temperatures, as
well as the Pd
mass were defined by
multivariate optimization. The limits of detection at the
optimized conditions were
230, 10, 200 and 800 pg for Ni, Cu, Fe and V, respectively.
Methods` accuracies
were confirmed by the analysis of oil certified reference
materials as well as by
comparison with independent methods. For all proposed
procedures, calibration
using aqueous analytical solutions was possible.
|
|||||||||||||||||||||||||||||||||
|