API MPMS 10.5 2013 pdf download.Manual of Petroleum Measurement Standards Chapter 10.5 Standard Test Method for Water in Petroleum Products and Bituminous Materials by Distillation.
3. Terminology 3.1 Definitions: 3.1.1 bituminous material, n—in petroleum technology, a black or dark-colored very viscous liquid or semi-solid com- posed principally of high molecular weight condensed aromatic, or naphthenic compounds, or both. 4. Summary of Test Method 4.1 The material to be tested is heated under reflux with a water-immiscible solvent, which co-distills with the water in the sample. Condensed solvent and water are continuously separated in a trap, the water settling in the graduated section of the trap and the solvent returning to the still. 5. Significance and Use 5.1 Aknowledge ofthe water content ofpetroleum products is important in the refining, purchase, sale, and transfer of products. 5.2 The amount of water as determined by this test method (to the nearest 0.05 or 0.1 volume %, depending on the trap size used) may be used to correct the volume involved in the custody transfer of petroleum products and bituminous mate- rials. 5.3 The allowable amount of water may be specified in contracts. 6. Solvent-Carrier Liquid 6.1 A water-immiscible solvent-carrier liquid that is mis- cible in the material being tested (see Table 1) shall be used. 6.1.1 Aromatic Solvent—The following aromatic solvents are acceptable: 126.96.36.199 Industrial Grade Xylene—(Warning—Flammable. Vapor harmful.) 188.8.131.52 Ablend of20 volume % industrial grade toluene and 80 volume % industrial grade xylene. (Warning—Flammable. Vapor harmful.) 184.108.40.206 Petroleum Naphtha or Coal Tar Naphtha, free of water, yielding not more than 5% distillates at 125°C (257°F) and not less than 20% at 160°C (320°F) and with a relative density (specific gravity) not lower than 0.8545 at 15.56/ 15.56°C (60/60°F). (Warning—Extremely flammable. Harm- ful if inhaled. Vapors may cause fire.)
6.1.2 Petroleum Distillate Solvent—A petroleum distillate solvent containing at least 2% (V/V) aromatics and with an initial boiling point (IBP) greater than 80°C (176°F); and a final boiling point (FBP) below 250°C (482°F) shall be used. N OTE 3—Examples of suitable solvents include Types I and IV and Classes A and B of Specification D235. N OTE 4—It is recommended to use a wide boiling range solvent with 10% boiling below 100°C to help to ensure an even distillation rate. 6.1.3 Volatile Spirits Solvent—The following volatile spirits solvents are acceptable: 220.127.116.11 Petroleum Spirit, with a boiling range from 100 to 120°C (212 to 248°F). (Warning—Flammable. Vapor harm- ful.) 18.104.22.168 Iso-octane, of 95% purity or better. (Warning— Extremely flammable. Harmful if inhaled. Vapors may cause fire.) 6.2 Solvent Blank—The water content ofthe solvent shall be determined by distilling an equivalent amount of the same solvent used for the test sample in the distillation apparatus and testing as outlined in Section 10. The blank shall be determined to the nearest scale division and used to correct the volume of water in the trap in Section 11. 7. Apparatus 7.1 General—The apparatus comprises a glass or metal still, a heater, a reflux condenser, and a graduated glass trap. The still, trap, and condenser may be connected by any suitable method that produces a leakproof joint. Preferred connections are ground joints for glass and O-rings for metal to glass. Typical assemblies are illustrated in Fig. 1, Fig. 2, and Fig. 3. The stills and traps should be chosen to cover the range of materials and water contents expected. On assembly, care shall be taken to prevent the joints from freezing or sticking. Always apply a very thin film of stopcock grease to prevent the glassware joints from seizing.
9. Verification 9.1 The accuracy of the graduation marks on the trap shall be certified or verified, using only national or international standards, such as National Institute of Standards and Technol- ogy (NIST) 4 traceable equipment. Verification shall be with a traceable 5 mL Micro Burette or Micro Pipette, readable to the nearest 0.01 mL. 9.1.1 In styles A, B, C, and D, as specified in Table 2 (Table 1 in Specification E123), each subdivision (that is, 0.1 mL through 1.0 mL) in the conical portion of the tube shall be verified. Thereafter, each major subdivision (that is, 2.0 mL, 3.0 mL, 4.0 mL, and up to the total volume ofthe trap) shall be verified. 9.1.2 In styles E and F, as specified in Table 2, each major subdivision (0.1 mL, 1.0 mL, 2.0 mL, 4.0 mL, and 5.0 mL in the case of Style E; 0.05 mL, 0.5 mL, 1.0 mL, 1.5 mL, and 2.0 mL in the case of Style F) shall be verified. 9.2 The entire glassware assembly shall be verified prior to first use and at a regular frequency thereafter as follows. 9.2.1 Put 400 mL ofdry (0.02 % water maximum) xylene or the solvent to be utilized in the analysis of unknown samples into the apparatus and test in accordance with Section 10. When complete, discard the contents of the trap and add the volume of water as specified as first test in Table 3 directly to the distillation flask and test in accordance with Section 10. 9.2.2 Repeat the test in 9.2.1, and add the volume specified as second test in Table 3 directly to the flask. The assembly of the apparatus is satisfactory only if the trap readings are within the tolerances specified in Table 3. 9.3 A reading outside the permissible limits suggests a malfunction resulting from vapor leaks, too rapid boiling, inaccuracies in calibration of the trap, or ingress of extraneous moisture. Eliminate these factors before repeating the verifica- tion.