1、Designation: D 2001 92 (Reapproved 2002)An American National StandardStandard Test Method forDepentanization of Gasoline and Naphthas1This standard is issued under the fixed designation D 2001; the number immediately following the designation indicates the year oforiginal adoption or, in the case of
2、 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 the removal of pentanes andlighter hydrocarbons from gasolines, naphth
3、as, and similarpetroleum distillates to prepare samples suitable for the deter-mination of hydrocarbon types in accordance with Test MethodD 1319 or Test Method D 2789. In addition, this test methoddetermines the volume percent of bottoms remaining afterdepentanization.1.2 The values stated in SI un
4、its are to be regarded as thestandard. The values given in parentheses are provided forinformation purposes only.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate sa
5、fety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:D 1250 Guide for Petroleum Measurement Tables2D 1319 Test Method for Hydrocarbon Types in LiquidPetroleum Products by Fluorescent Indicator Adsorption2D 2789 Te
6、st Method for Hydrocarbon Types in Low-Olefinic Gasoline by Mass Spectrometry23. Summary of Test Method3.1 A 50-mL sample is distilled into an overhead (C5andlighter) fraction and a bottoms (C6and heavier) fraction. Thevolume of bottoms is measured and the volume percent, basedon the charge, is calc
7、ulated.4. Significance and Use4.1 The presence of pentane and lighter hydrocarbons ingasolines, naphthas, and similar petroleum distillates interferesin Test Method D 1319 and Test Method D 2789. Pentane andlighter hydrocarbons are separated by this test method so thatthe depentanized residue can be
8、 analyzed and so the pentaneand lighter hydrocarbons can be analyzed by other methods, ifdesired.4.2 Under the conditions specified in the test method someC5and lighter hydrocarbons remain in the bottoms, and someC6and heavier hydrocarbons carry over to the overhead.Expressed as volume percent of ch
9、arge, the amounts aretypically 2 % or less, which is considered adequate for thepurpose designated under Scope. It should be recognized,however, that when expressed as volume percent of overheador of bottoms the percentages can be higher, making this testmethod unsuitable for any purposes not design
10、ated underScope.5. Apparatus5.1 Depentanization Apparatus, as shown in Fig. 1, consist-ing of the following parts:5.1.1 Distillation Column,5.1.2 Reflux Condenser Head,5.1.3 Light-Ends Trap,5.1.4 Receiver, graduated, 12.5 mL, and5.1.5 Thermometer,310 to 79C (50 to 175F).5.2 Column PackingTwo types a
11、re required:5.2.1 Heli-Pak Column Packing,41.27 by 2.54 by 2.54 mm(Size B, 0.050 by 0.100 by 0.100 in.).5.2.2 Heli-Pak Column Packing,4Size C, 4.4 by 4.4 m(0.090 by 0.175 by 0.175 in.), or Cannon Protruded MetalPacking,54.0 by 4.0 mm (0.16 by 0.16 in.).5.3 Distillation Flask, round-bottom, 100 mL, w
12、ith2440 standard-taper female joint.5.4 Distillation Flask Heating Mantle, Glas-Col, spherical,for 100-mL flask.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.04 on Hydrocarbon Analysis.Current
13、 edition approved March 15, 1992. Published May 1992. Originallypublished as D 2001 62 T. Last previous edition D 2001 91.2Annual Book of ASTM Standards, Vol 05.01.3Thermometer No. ME510-1 available from Metro Scientific Inc., 11 WillowPark Center, East Farmingdale, NY 11735.4Available from Reliance
14、 Glass Works Inc., Gateway Rd., PO Box 825,Bensenville, IL 60106.5Cannon protruded metal packing available from Scientific Development Co.,Box 795, State College, PA.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.5 Variable Transf
15、ormer, for regulating power to heatingmantle.5.6 Water Cooling BathIf a supply of chilled water for thereflux condenser is not available, a satisfactory means forsupplying chilled water can be provided by circulating tapwater through coiled copper tubing immersed in an ice-waterbath.6. Preparation o
16、f Apparatus6.1 Fill the fractionating column with packing as follows:Place about 25 mm (1 in.) of the Heli-Pak column packing, sizeC or the Cannon packing on the indentations at the bottom ofthe column. This packing assures ample free space to preventflooding at the bottom of the column. Fill the co
17、lumn to within25 mm (1 in.) of the top of the jacket with Heli-Pak columnpacking, size B. (The performance of this packing is notsensitive to the exact manner of pouring into the column.)6.2 Assemble and connect the column, head, light-ends trap,and the receiver. Mount the assembly on a suitable sup
18、port.6.3 Insert the thermometer through the side-arm at the top ofthe column.NOTE 1The calibration of the thermometer at the cut temperatureshould be checked by refluxing a pure compound. Such a calibration canshow a need for a correction.6.4 Immerse the receiver in a Dewar flask containing amixture
19、 of solid carbon dioxide (WarningExtremely cold.)in a suitable liquid. 1,1,2 Trichloro Ethene is recommended.(WarningHealth hazard.)6.5 Circulate water, chilled to a temperature between 4 and10C (40 and 50F), through the reflux condenser.7. Procedure7.1 Lubricate the joint at the bottom of the colum
20、n with ahydrocarbon-insoluble grease, such as silicone, starch-glycerol, or metallic soap. Place the heating mantle around theflask. With a 50-mL graduated cylinder, measure 50 mL of thesample. Determine its temperature, and transfer it to the flask.Connect the flask immediately to the column.7.2 Co
21、nnect the mantle, through the variable transformer, tothe power supply.7.3 Apply heat to the contents of the flask at a uniform rate.NOTE 2With the apparatus prepared as described in Section 6, asetting of 30 on the transformer usually provides a satisfactory initialheating rate; voltage is increase
22、d as required.7.4 As soon as drops of liquid reflux form at the columnhead, adjust the position of the condenser so that one drip-tipfeeds to the take-off line, and the other back to the (WarningExtremely flammable liquid.) column. The reflux condenserremains in this position throughout the distilla
23、tion to provideabout a 1 + 1 reflux ratio.NOTE 3Low-boiling light ends will condense on the light-ends trapFIG. 1 Depentanization ApparatusD 2001 92 (2002)2and collect in the receiver before drops of liquid reflux form at the columnhead.7.5 The distillation rate should not exceed 30 to 40 drops/30s
24、from each tip of the reflux condenser.7.6 Continue the distillation until the thermometer indicatesa temperature of 49C (120F). When this temperature isreached, shut off the heat and drop the lower portion of theheating mantle. Turn the reflux condenser so that drops fromboth drippers are returned t
25、o the column. Direct a stream of airon the top surface of the flask. Perform the above steps in rapidsuccession.7.7 Allow the column to drain and the contents of the flaskto cool for 30 min.7.8 Remove the flask from the column, and carefullytransfer the contents to the same graduated cylinder which
26、wasused to measure the charge. Measure the volume of the bottomsfraction and determine its temperature.8. Calculation8.1 If the temperatures of the distillation charge and bottomsdiffer by more than 11C (20F), correct the measured volumesto volumes at 15C (60F) by Guide D 1250.8.2 Calculate the volu
27、me of bottoms in percent as follows:Volume of bottoms, percent 5 A/B! 3 100 (1)where:A = volume of bottoms, mL andB = volume of the charge, mL.9. Precision and Bias9.1 The following criteria should be used for judging theacceptability of results (95 % confidence) (Note 4):9.1.1 RepeatabilityThe diff
28、erence between two test re-sults, obtained by the same operator with the same apparatusunder constant operating conditions on identical test material,would in the long run, in the normal and correct operation ofthe test method, exceed 2 volume % only in one case in twenty.9.1.2 ReproducibilityThe di
29、fference between two singleand independent results obtained by different operators work-ing in different laboratories on identical test material would, inthe long run, in the normal and correct operation of the testmethod, exceed 4 volume % only in one case in twenty.9.2 BiasThe quantities determine
30、d are defined by theconditions used in this empirical test method, and a statementof bias is therefore not appropriate.NOTE 4Precision data are based on results obtained by five laborato-ries testing four samples in duplicate. The samples contained C5-and-lighter fractions covering a range of 5 to 2
31、5 volume %.10. Keywords10.1 depentanization; fractionations; hydrocarbon types;pentanesASTM International takes no position respecting 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
32、the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard 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. Y
33、our comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your commen
34、ts have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This 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).D 2001 92 (2002)3
