Abstract:
Eighteen
trace heavy metals were
quantitatively analyzed using atomic
absorption spectroscopy; five samples of petroleum products were collected from
Kaduna Refining and Petrochemical Company
. Three different preparation
methods wer
e adopted for the determination of trace and heavy metals present
in the various petroleum products viz:
Direct sample aspiration into the
flame
after solvent dilution,
Total acid
(wet) digestion of the sample,
Ashing of the
sample and dissolution with an
appropriate acid.
Sample treatment with organic
acid prior to aspiration proved to be more reliable and it gave good results for
trace and heavy metals in petroleum products except for kerosene sample,
where most of the elements responded positively to ash
ing preparation method.
The level of eighteen elements analyzed in Petrol (PMS), Kerosene (DPK), Gas
Oil (AGO), LPFO and Residual fuel are shown in table 3.7 which revealed t
hat
Potassium(120 mg/l,
340
mg/l, 120 mg/l, 2900 mg/l, 2050 mg/l) and
Sodium
(
26
0
mg/l,
180
mg/l, 160
mg/l,
1800
mg/l,
1200
mg/l) are the most abundant
elements in both the five sample under study followed by Iron
(
1.20
mg/l,
1.74
mg/l,
1.25
mg/l,
0.60
mg/l),
Manganese
(
1.28
mg/l,
1.04
mg/l,
1.46
mg/l,
6.6
mg/l4.8
mg/l),
Lead
(
0.50
mg/l
,
0.16
mg/l,
0.40
mg/l,
27.8
mg/l,
24.6
mg/l)
and
Aluminium (0.42
mg/l,
1.06
mg/l,
0.32
mg/l,
0.82
mg/l,
24.6
mg/l).
The
concentration ranges of trace heavy metals analyzed are within the permissible
levels set by World Health Organisation.
