ISSN 1070-4272, Russian Journal of Applied Chemistry, 2006, Vol. 79, No. 9, pp. 1546!1549. + Pleiades Publishing, Inc., 2006.
Original Russian Text + N.B. Ivanenko, A.A. Ivanenko, E.V. Molodkina, E.B. Nosova, A.E. Zeimal’, Yu.A. Zavoda, 2006, published in Zhurnal Prikladnoi
Khimii, 2006, Vol. 79, No. 9, pp. 1562!1565.
OF FOSSIL FUEL
Direct Atomic-Absorption Determination of the Ni and V
Content in Oil
N. B. Ivanenko, A. A. Ivanenko, E. V. Molodkina, E. B. Nosova,
A. E. Zeimal’, and Yu. A. Zavoda
St. Petersburg State University, St. Petersburg, Lyumeks NPF AP, St. Petersburg, Russia
Received April 20, 2006
Abstract-A direct (without sample pretreatment) atomic-absorption method of V and Ni determination in oil
with electrothermal atomization and Zeeman correction of background was developed.
About 30 metals were detected in oil, among which
V, Ni, Fe, Cu, Al, Cr, and Zn are the most abundant.
Vanadium and nickel were the first metals detected in
oil. The content of these metals in oil can reach tenth
parts of percent, which makes recovery of vanadium
and nickel from oil economically attractive . Ap-
proximately 40% of vanadium and nickel exist in oil
as vanadyl and nickel porphyrins and are concentrated
in oil fractions with boiling points above 300oC, i.e.,
in raw material of catalytic cracking, black oil, and tar
. The presence of vanadium and nickel in these
fractions is undesirable because of catalyst poisoning
and corrosion of boiler parts with vanadium(V) oxide,
which is formed in the course of fuel combustion.
Vanadium and nickel compounds are the most
hazardous among all metals discharged into the en-
vironment from petrochemical plants. They have
toxicological, immunopathological, and carcinogenic
effect on a human body.
The vanadium and nickel content in oil and in its
heavy fractions is usually determined by various in-
strumental methods [3, 4]. There is a standard method
of vanadium determination , in which oil samples
are preliminarily treated with concentrated sulfuric
and nitric acids, or elemental sulfur, or samples are
burnt. The ash is treated with acids, which is followed
by photometric determination of vanadium as a tung-
state complex at 436 nm. The standard method of
determination of metals in oil in the United States
involves oil sample treatment with concentrated sul-
furic acid, followed by heating to 525oC in muffle, or
sample dissolution in a complex mixture of aromatic
solvents. The final determination is performed on
atomic absorption spectrometers with flame atomiza-
tion or on atomic emission spectrometers with induc-
tively coupled plasma .
In this study, we developed a method of vanadium
and nickel determination in oil on a atomic absorption
spectrometer with electrothermal atomization and
Zeeman correction of the background.
An MGA-915 Zeeman atomic absorption spectrom-
eter produced by Lyumeks Limited Liability Com-
pany, Massman graphite cells with L’vov’s platform,
and 5350 mm
single-channel pipettes (batcher) were
used; the measurement error did not exceed 5%.
We used a 1 g dm
aqueous solution of nickel
[GSO (State Reference Sample) 8001393(8003396),
Water Research and Control Center], a 0.1 g dm
aqueous solution of vanadium (GSO 7267396, Ural
Research Institute of Metrology), distilled water
[GOST (State Standard) 6709372], double-distilled
water (the metal content should not exceed 30% of the
lower boundary of the interval determined), ultrapure
grade palladium nitrate (10 g dm
) as a modifier, ul-
trapure grade concentrated nitric acid (GOST 11 1253
84), and calibration solutions of Ni and V(IV) (10 and
) prepared in double-distilled water.
To plot the calibration dependence of the analytical
signal on the element weight, before each measure-
ment 20 mm
of a 1 g dm
modifier solution was
introduced with a batcher into a graphite cell of the
MGA-915 atomic absorption spectrometer and dried
for 40 s at 110oC. Then the required volume (53