Trace metals in gasoline are a major source of environmental pollution. They can also adversely affect the performance of automotive engines. Silicon (Si) contamination can be especially problematic as deposits damage components such as catalytic convertors and oxygen sensors leading to costly repairs. ICP-OES is often used for the determination of trace elements in petroleum products due to its reliability, robustness and sensitivity. A successful analysis needs to take account of sample characteristics, such as the high volatility of gasoline. Continuous loading of the plasma with gasoline can affect the stability of the signal and lead to carbon build up on the torch that may cause the plasma to extinguish. 2 In this study, the Agilent 5100 Synchronous Vertical Dual View (SVDV) ICP-OES was used for the analysis of 21 elements in gasoline, including Si. Oxygen was added to the auxiliary argon gas flow to reduce carbon build up on the torch, maintain a stable plasma and reduce carbon emission from the organic solvent. A programmable temperature spray chamber, set to -10 °C, was used to reduce vapor loading on the plasma, ensuring a more stable plasma. 安捷倫 5100 ICP-OES