
【国外标准】 Standard Test Method for Acid Number of Petroleum Products by Potentiometric Titration
本网站 发布时间:
2024-02-28
开通会员免费在线看70000余条国内标准,赠送文本下载次数,单本最低仅合13.3元!还可享标准出版进度查询、定制跟踪推送、标准查新等超多特权!  
查看详情>>

适用范围:
5.1 New and used petroleum products, biodiesel, and blends of biodiesel may contain acidic constituents that are present as additives or as degradation products formed during service, such as oxidation products. The relative amount of these materials can be determined by titrating with bases. The acid number is a measure of this amount of acidic substance in the oil, always under the conditions of the test. The acid number is used as a guide in the quality control of lubricating oil formulations. It is also sometimes used as a measure of lubricant degradation in service. Any condemning limits must be empirically established.5.2 Since a variety of oxidation products contribute to the acid number and the organic acids vary widely in corrosion properties, the test method cannot be used to predict corrosiveness of oil or biodiesel and blends under service conditions. No general correlation is known between acid number and the corrosive tendency of biodiesel and blends or oils toward metals.1.1 This test method covers procedures for the determination of acidic constituents in petroleum products, lubricants, biodiesel, and blends of biodiesel.1.1.1 Test Method A—For petroleum products and lubricants soluble or nearly soluble in mixtures of toluene and propan-2-ol. It is applicable for the determination of acids whose dissociation constants in water are larger than 10–9; extremely weak acids whose dissociation constants are smaller than 10–9 do not interfere. Salts react if their hydrolysis constants are larger than 10–9. The range of acid numbers included in the precision statement is 0.1 mg/g KOH to 150 mg/g KOH.1.1.2 Test Method B—Developed specifically for biodiesel and biodiesel blends with low acidity and slightly different solubility. This test method requires the use of an automatic titrator with automatic endpoint-seeking capability.NOTE 1: In new and used oils, the constituents that may be considered to have acidic characteristics include organic and inorganic acids, esters, phenolic compounds, lactones, resins, salts of heavy metals, salts of ammonia and other weak bases, acid salts of polybasic acids, and addition agents such as inhibitors and detergents.1.2 The test method may be used to indicate relative changes that occur in oil during use under oxidizing conditions regardless of the color or other properties of the resulting oil. Although the titration is made under definite equilibrium conditions, the test method is not intended to measure an absolute acidic property that can be used to predict performance of oil under service conditions. No general relationship between bearing corrosion and acid number is known.NOTE 2: The acid number obtained by this standard may or may not be numerically the same as that obtained in accordance with Test Methods D974 and D3339. There has not been any attempt to correlate this method with other non-titration methods.NOTE 3: A few laboratories have made the observation that there is a difference in Test Method D664 results when aqueous versus nonaqueous buffers are used.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
标准号:
ASTM D664-18e2
标准名称:
Standard Test Method for Acid Number of Petroleum Products by Potentiometric Titration
英文名称:
Standard Test Method for Acid Number of Petroleum Products by Potentiometric Titration标准状态:
Active-
发布日期:
-
实施日期:
出版语种:
- 推荐标准
- ASTM 51401-21 Standard Practice for Use of a Dichromate Dosimetry System
- ASTM 51956-21 Standard Practice for Use of a Thermoluminescence-Dosimetry System (TLD System) for Radiation Processing
- ASTM A1010/A1010M-24 Standard Specification for Higher-Strength Martensitic Stainless Steel Plate, Sheet, and Strip
- ASTM A1016/A1016M-24 Standard Specification for General Requirements for Ferritic Alloy Steel, Austenitic Alloy Steel, and Stainless Steel Tubes
- ASTM A105/A105M-24 Standard Specification for Carbon Steel Forgings for Piping Applications
- ASTM A1064/A1064M-24 Standard Specification for Carbon-Steel Wire and Welded Wire Reinforcement, Plain and Deformed, for Concrete
- ASTM A108-24 Standard Specification for Steel Bar, Carbon and Alloy, Cold-Finished
- ASTM A1080/A1080M-24 Standard Practice for Hot Isostatic Pressing of Steel, Stainless Steel, and Related Alloy Castings
- ASTM A1090/A1090M-19(2024) Standard Specification for Forged Rings and Hollows for Use as Base Plates in Power Transmission Structures
- ASTM A1115/A1115M-24 Standard Practice for Construction of Mechanically Stabilized Earth Walls with Inextensible Soil Reinforcement
- ASTM A1128-24 Standard Specification for Stainless Steel Shielded, Rubber Gasketed Couplings Having an Integral Restraint Feature for Joining Hubless Cast Iron Soil Pipes and Fittings Where External Restraint Is Required
- ASTM A179/A179M-24 Standard Specification for Seamless Cold-Drawn Low-Carbon Steel Heat-Exchanger and Condenser Tubes
- ASTM A234/A234M-24 Standard Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and High Temperature Service
- ASTM A242/A242M-24 Standard Specification for High-Strength Low-Alloy Structural Steel
- ASTM A249/A249M-24a Standard Specification for Welded Austenitic Steel Boiler, Superheater, Heat-Exchanger, and Condenser Tubes