1. Scope
1.1 This test method covers a potentiometric titration procedure for determining the existent inorganic sulfate content of hydrous, anhydrous ethanol, and anhydrous denatured ethanol, which is added as a blending agent with spark ignition fuels. It is intended for the analysis of denatured ethanol samples containing between 1.0 - 20 mg/kg existent inorganic sulfate.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Material Safety Data Sheets are available for reagents and materials. Review them for hazards prior to usage.
2. Referenced Documents
2.1 ASTM Standards:
D1193 Specification for Reagent Water
D4052 Test Method for Density, Relative Density, and API Gravity of Liquids by Digital Density Meter
D4057 Practice for Manual Sampling of Petroleum and Petroleum Products
D4177 Practice for Automatic Sampling of Petroleum and Petroleum Products
D6299 Practice for Applying Statistical Quality Assurance and Control Charting Techniques to Evaluate Analytical Measurement System Performance
3. Terminology
3.1 Definitions:
3.1.1 existent inorganic sulfate, n - inorganic sulfate species actually present in the sample at the time of analysis with no oxidation treatment.
3.1.1.1 Discussion - Specifically in this test method, inorganic sulfate is present as sulfate in ethanol.
3.1.2 inorganic sulfate, n - sulfate
species present as sulfuric acid, ionic salts of this acid, or mixtures of these.