The analyses of trace metals in Nigerian petroleum products is very important considering the detrimental effect of these metals in refining processes and environment in general. Also, the data on the concentration of trace metals in Nigerian indigenous petroleum products are limited. This research study aimed at determining and comparing the concentration of trace metals in different Nigerian petroleum products from Kaduna refinery. 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 of analysis were adopted for the determination of trace and heavy metal present in the various petroleum products, viz; direct sample aspiration in to 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 gave good results for trace and heavy metals in petroleum products except for kerosene sample, where most of the elements responded positively to ashing preparation method. The level of eighteen elements analyzed in petrol (PMS), kerosene (DPK), Automotive Gas Oil (AGO), LPFO (Low pour fuel oils) and Residual Fuel revealed that potassium and sodium are the most abundant elements in both the five sample under study followed by iron, manganese, lead and aluminum. which revealed that Potassium (120 mg/l, 340 mg/l, 120 mg/l, 2900 mg/l, 2050 mg/l) and Sodium (260 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, Manganese, Lead and Aluminum respectively. The concentration ranges of trace heavy metals analyzed are within the permissible levels set by World Health Organization.
Key words: KEYWORDS: Trace metal, heavy metals, Atomic Absorption Spectroscopy, Nigerian petroleum products, Kaduna Refinery.
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