1、Designation: D 4056 01 (Reapproved 2006)An American National StandardStandard Test Method forEstimation of Solubility of Water in Hydrocarbon andAliphatic Ester Lubricants1This standard is issued under the fixed designation D 4056; the number immediately following the designation indicates the year
2、oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers a procedure for estimating theeq
3、uilibrium solubility of water and its vapor in hydrocarbonand aliphatic ester lubricants, at temperatures between 277 and373 K. The test method is limited to liquids of low to moderatepolarity and hydrogen bonding, with predicted solubilities notover 1000 ppm by weight in hydrocarbons, or 30 000 ppm
4、 byweight in oxygenated compounds, at 298 K.1.2 Specifically excluded are olefins, nitriles, nitro com-pounds, and alcohols.1.3 This test method is recommended only for liquids notcontaining widely different chemical species. This excludesblends of esters with hydrocarbons, and lubricants containing
5、detergents, dispersants, rust preventives, or load carryingadditives.1.4 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use.
6、It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D94 Test Methods for Saponification Number of PetroleumProductsD 1218 Test Met
7、hod for Refractive Index and RefractiveDispersion of Hydrocarbon LiquidsD 1298 Test Method for Density, Relative Density (SpecificGravity), or API Gravity of Crude Petroleum and LiquidPetroleum Products by Hydrometer MethodD 2502 Test Method for Estimation of Mean Relative Mo-lecular Mass of Petrole
8、um Oils from Viscosity Measure-mentsD 3238 Test Method for Calculation of Carbon Distributionand Structural Group Analysis of Petroleum Oils by then-d-M Method3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 charge transfer parameterthe portion of the solu-bility parameter not
9、attributed to London or Keesom forces.3.1.1.1 DiscussionIt includes hydrogen bonds, induceddipoles, and other quasichemical forces.3.1.1.2 DiscussionThe square of the solubility parameterequals the sum of the squares of the three partial parameters.3.1.2 dispersion parameterthe portion of the solubi
10、lityparameter attributed to London forces.3.1.3 polar parameterthe portion of the solubility param-eter attributed to Keesom (permanent dipole) forces.3.1.4 solubility parameterthe square root of the cohesiveenergy density (heat of vaporization minus work of vaporiza-tion, per unit volume of liquid)
11、, at 298 K.3.2 Symbols:CA= percentage of aromatic carbons,CN= percentage of naphthenic carbons,d = density of lubricant at 298 K, g/mL,G = solubility by weight, mg/kg (ppm),M = molecular weight of lubricant, g/mol,nD= refractive index of lubricant at 298 K,RH = relative humidity, %,S = saponificatio
12、n number, mg of KOH/g of lubricant,T = system temperature, K,V = molar volume of lubricant, mL/mol,x = mole fraction of water in equilibrium mixture,y = Lorentz-Lorenz refractivity function,dd= dispersion parameter, (MPa)0.5,P = polar parameter, (MPa)0.5,H = charge transfer parameter, (MPa)0.5,f1= v
13、olume fraction of lubricant in equilibrium mixture,and1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.11 on Engineering Sciences of High Performance Fluids and Solids.Current edition approved Ju
14、ly 1, 2006. Published August 2006. Originallyapproved in 1981. Last previous edition approved in 2001 as D 4056 01.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to t
15、he standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.f2= volume fraction of water in equilibrium mixture.4. Summary of Test Method4.1 Data required are the density, refractive index, a
16、ndmolecular weight of a hydrocarbon. The saponification numberis also required for an ester. From these are calculated thecarbon distribution for a hydrocarbon, and then the partialsolubility parameters. These in turn are used to calculate thevolume fraction of water dissolved at 298 K at saturation
17、. Thisis converted to mole fraction, and adjusted to system tempera-ture. The mole fraction is then converted to solubility byweight. If the system atmosphere is not saturated, the solubilityis multiplied by the relative humidity.5. Significance and Use5.1 Knowledge of the water content is important
18、 in lubrica-tion, as large amounts of water can cause corrosion fatigue insteel bearings, and the complete absence of water can causemetal scuffing.5.2 High water content has an accelerating effect on oxida-tion of lubricants, and can also contribute to foaming, espe-cially at high altitude or tempe
19、rature, or both.6. Procedure6.1 Calculate the molar volume of the lubricant as follows:6.1.1 Determine the density at 298 K by Test MethodD 1298 or equivalent. If the density at 293 K is known (asrequired for Test Method D 3238) multiply it by 0.996 toobtain d with sufficient accuracy.6.1.2 Determin
20、e the molecular weight by Test MethodD 2502.6.1.3 Calculate the molar volume as follows:V 5 M/d (1)6.2 Calculate the dispersion parameter by these steps:6.2.1 Determine the refractive index at 298 K by TestMethod D 1218.If a value at 293 K is known (as required for Test MethodD 3238) multiply it by
21、0.998 to obtain nDwith sufficientaccuracy.6.2.2 Calculate the refractivity function as follows:y 5 nD22 1!/nD21 2! (2)6.2.3 Calculate the parameter as follows:dd5 45y32 119y21 108 y 2 4.58 (3)6.3 For hydrocarbons, calculate ddand P as follows:6.3.1 Determine CAand CNby Test Method D 3238.6.3.2 Calcu
22、late the parameters as follows:P 5 0.0143CAand (4)H 5 0.0286CA1 0.0143CN(5)6.4 For esters, calculate P and H as follows:6.4.1 Determine the saponification number by Test MethodsD94.6.4.2 Calculate the parameter as follows:P 5 0.00815 Sd and (6)H 5 0.00173 SM/V0.5(7)6.5 Calculate the volume fraction
23、of water at 298 K andsaturation as follows:f25 exp 0.00726 f2118.00 2dd!21 2.39 15.552 P!21 2.39 16.27 2 H!2! 1 1 2 18/V!f1# (8)NOTE 1For hydrocarbons, it may be safely assumed that f1= 1.00.However, that can introduce a significant error for some esters, socalculate f2stepwise. Start with f1= 1.00,
24、 next step f1=1f2from thefirst step, and so on until no further significant change is noted.6.5.1 Rarely are more than three steps needed to obtainconstancy to three significant figures. A small programmablecalculator, which is strongly recommended for the wholeprocedure, can readily be set into the
25、 interative cycle described.6.6 Calculate the mole fraction at 298 K as follows:x 5 Vf2/18 (9)6.7 Calculate the solubility by weight at 298 K, using Eq 10:G 5 18 3 106X/M1 2 X! (10)6.8 If the system was not saturated at equilibrium, with atleast a trace of liquid water present, multiply X by RH/100;
26、then convert to G as before. (Unless G is larger than 1000, thisadjustment can be made directly on it.)6.9 Multiply G by RH/100, if the system was not saturated,with at least a trace of liquid water present. If G is greater than1000, multiply X by RG/100 before converting to G.7. Precision and Bias7
27、.1 PrecisionThe repeatability and reproducibility inter-vals arise entirely from those of the experimental methodsemployed for n, S, CAand CN. The intervals due to the statedprecision of Test Method D 1218 will both be 0.4 % of thecalculated solubility. The effects of the intervals stated for TestMe
28、thods D 94 and D 3238 are such that no blanket statementcan be made. However, the intervals for any specific lubricantcan readily be calculated by processing the values of S, CA, andCNthrough the equations alone and plus the intervals from theexperimental methods.7.1.1 Predictions have been made for
29、 all pure hydrocarbonsfor which solubilities of water at 298 K were listed, exceptingthe olefins, by API,3Riddick,4and Polak.5On aliphatics,Polaks values were chosen if available since they werecarefully compared against the older data, giving 14 points.Riddick yielded three, and API two accepted, p
30、lus six rejectedsimply because they appeared “wild.” All 18 points werepredicted within 610 %. The API and Riddick values weresimilar on naphthenes; five values were predicted within 20 %and one within 50 %. Polaks six values for aromatics werepredicted within 10 %, and five others from Riddick with
31、in15 %.API had only one that was neither redundant nor wild; itwas predicted within 10 %.3API Technical Data Book, American Petroleum Institute, Washington, DC1970.4Riddick, J. A., and Bunger, W. E., Organic Solvents, (Techniques of OrganicChemistry, Vol. 2, A. Weissberger, Ed.) Wiley-Interscience,
32、John Wiley and Sons,New York, NY 1970.5Polak, J., and Lu, B. C.-Y., “Mutual Solubilities of Hydrocarbons and Water,”Canadian Journal of Chemistry, Vol 51, 1973, pp. 40184023.D 4056 01 (2006)27.1.2 Predictions at elevated temperatures had to be checkedagainst API data, and were within 10 % of the cor
33、rect slopefrom 298 to 373 K for the three liquids covering this range.Most of the data stop at 323 K or less, and have not beenanalyzed.7.1.3 API lists eight commercial oils with solubilities atelevated temperatures. Assigning plausible dd, CA, and CNvalues gave predictions on five of these within 5
34、0 % or betterfor solubility, and 25 % or better for slope. The gasolinetemperature range was too short to test, and the JP-3 and 4 dataappeared wild.7.1.4 Data by Cantley6on a petroleum (SAE 5W) oil, asynthetic hydrocarbon, and two esters at 311 K were predictedwithin 20 %, and the dependence on RH
35、within 10 %. Otherdata also illustrate the problems caused by additives.7.1.5 Riddick shows data on 34 esters. However, only 13 ofthose meet the criteria in the scope, and two of these wereclassified as wild because of obvious conflicts with closeisomers. The remaining eleven were predicted within 5
36、0 % ofthe true value, and most within 30 %.7.2 BiasNo general statement is made for bias for this testmethod since the data used to determine the correlation cannotbe compared with accepted reference material.8. Keywords8.1 lubricants; solubility; waterASTM International takes no position respecting
37、 the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standar
38、d is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International
39、 Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.Thi
40、s standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).6Cantley, R. E., “The Effect of Water in Lubricating Oil on Bearing FatigueLife,” ASLE Transactions, Vol 20, 1977, pp. 244248.D 4056 01 (2006)3
