Petrol engines are widely used in variety of vehicles due to its fuel efficiency and low maintenance compared to the other fuel engines. Even though Petrol engine exhaust has less Carbon Monoxide (CO) and Hydrocarbon (HC) than Diesel engine exhaust, it posses considerable amount of Particulate Matter (PM) and Oxides of Nitrogen (NOx). Poly Aromatic Hydrocarbon (PAH) emissions from Petrol engines, as a part of Soluble Organic Fraction (SOF) of Petrol particulates, are of concern as most of them are carcinogenic. The sample was collected by using series of water bubblers and condensate traps immersed in an ice- water bath. The soluble organic fraction, which is present in the collected sample, was extracted in the soxhlet extraction apparatus. The determination of PAH present in the Soluble Organic Fraction (SOF) was estimated by High performance Thin Layer Chromatography (HPTLC). An investigation into the effects of octane number and octane improvers on engine emissions was conducted using 11 test fuels- having octane number in the range of 89-940N

Key words: Poly Aromatic Hydrocarbon, Particulate Matter, Oxides of Nitrogen, Soluble Organic Fraction, High Performance
Thin Layer Chromatography