scope:

This method is for the determination of silicon (Si) in petroleum liquids using an Inductively Coupled Plasma - Mass Spectrometer (ICP-MS). Silicon is typically present in petroleum liquids as soluble organic silicones, but the method will also detect other forms of silicon such as the generally insoluble inorganic silicon salts and silica. The method is primarily used to analyze reformer charge stocks for silicones, but may also be used for refinery charge stocks as heavy as vacuum gas oil (VGO). The lower limit of quantitation is less than 0.1 mg/kg (mass-ppm) as silicon. Less sensitive tests for trace silicon are UOP Method 796, "Silicon in Petroleum Liquids by ICP-OES," (to 1 mg/kg) and ASTM Method D7757, "Silicon in Gasoline and Related Products by Monochromatic Wavelength Dispersive X-ray Fluorescence Spectrometry," (to 3 mg/kg).