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T h e bottle shall be closed immediately with a tight- fitting stopper, and placed in an ice bath or refrigerator capable of bringing the gasoline to a temperature of not less than 32°F
4Ib 9009276 0019816 8T5 = An American National Standard British Standard 4717 NOTICE: This standard has either been superseded and replaced by a new version or discontinued Contact ASTM International (www.astm.org) for the latest information Designation: D 216 - 77 (Reapproved 1982) Designation: 191/65 (75) Standard Method for DISTILLATION OF NATURAL GASOLINE’ This standard is issued under the fixed designation D 216; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision.A number in parenthesesindicates the year of last reapproval.This is also a standard of the Institute of Petroleum issued under the fixed designation IP 19 I The final number indicates the year of last revision This method was issued as a joint A S T M - I P standard in 1965 This method has been adoptedf o r use by government agencies to replace Method 1015 of Federal Test Method Standard No 791b 1 Scope cation E 133 1.1 This method covers the distillation of 5.1.1 Flask -Standard 100-ml distillation natural gasoline flask NOTE 1-The values stated in inch-pound units 5.1.2 Condenser and Cooling Bath 5.1.3 Shield, Type 1 or 2 are to be regarded as the standard 5.1.4 Flask Support, Type 1 or 2 with 2 Applicable Documents board Type A 5.1.5 Graduared Cylinder, 100-ml 2.1 ASTM Standards: 5 I 6 Gas Burner -A burner so con- E 1 Specification for ASTM Thermometer? E 133 Specification for Distillation Equip- structed that heat can be obtained to distill the product at the rate specified The flame shall ment’ never be so large that it spreads over a circle of diameter greater than 4’/2 in (11 5 mm) on 3 Summary of Method the under surface of the asbestos board A sensitive regulating valve and gas pressure 3 1 A sample of 1 0 0 ml is distilled at at- governor are desirable adjuncts, as they give mospheric pressure without fractionation, and complete control of heating readings are taken of the vapor temperatures corresponding to the amounts distilled 5.1.7 Electric Heater -An electric heater may be used instead of the gas burner and 4 Significance shall be capable of bringing over the first drop within the time specified in 8.1 when started 4 1 Natural gasoline is so volatile that it cold, and of continuing the distillation at a must be handled, measured, condensed, and uniform rate (A heater unit of low-heat ca- recovered at lower temperatures than most pacity, adjustable from O to 750 W, has been petroleum products This method incorpo- found satisfactory) When an electric heater is rates handling and other precautions for pre- employed, the portion of the shield above the cision ’ This method is under the jurisdiction of ASTM Committee 4.2 A n indication of the volatility blending characteristics that a natural gasoline will ex- D-2 on Petroleum Products and Lubricants hibit when blended with refinery stocks to In the IP this method is under the jurisdiction of the Stan- make a finished gasoline is obtained from the results of this type of distillation dardization Committee Current edition approved Aug 26 1977 Published October 5 Apparatus 1977 Originally published as D216-25 Last prexious edition 5.1 The apparatus listed in the following, D216-54 (1976) 5.1.1 through 5.1.5, shall conform to Specifi- 4miral Book oj’ASTM Slandards, Vols 05.03 and 14.01 ’ Iwiirol Book ofAS7’M Standards Vols 05.03 and 14.02 lA4 = - ~ W 900927b 0019817 731 D216- @ 191 board shall be the same as with the gas 7.5 Fit the thermometer (previously cooled burner, but the part below the board may be omitted to a temperature of 32 to 40°F (O to 4.5"C) 5.1.8 Thermometer, having a range as and dried) tightly into the flask with a suitable shown below and conforming to the require- cork so that it will be in the middle of the ments for ASTM Thermometer 7 F or 7C, as neck, and so that the lower end of the capil- prescribed in Specification E 1, or IP ther- lary tube is on a level with the inside of the mometer 5C bottom of the vapor outlet tube at its junction with the neck of the flask Thermometer Number 7.6 Place the charged flask in the 11/4-in Temperature Range ASTM IP (32-mm) opening in the 6 by 6-in (150 by 150-mm) asbestos board with the vapor outlet - 2 to +3OO0C 7c 5c tube inserted into the condenser tube A tight 30 to 580°F connection must be made by means of a cork 7F through which the vapor tube passes Adjust the position of the flask so that the vapor tube 6 Sampling extends into the condenser tube not less than 1in (25 mm) nor more than 2 in (50 mrn) 6.1 Samples should be collected in a previ- ously cooled bottle, preferably by immersing 7.7 Place the graduated cylinder used in the bottle in the liquid, where possible, and measuring the charge without drying, at the discarding the first sample Where immersion outlet of the condenser tube in such a position is not possible the sample should be drawn off that the condenser tube shall extend into the into a previously cooled bottle in such a man- cylinder at least 1 in (25 mm), but not below ner that agitation is kept at a minimum The the 100-ml mark Immerse the graduated cyl- bottle shall be closed immediately with a tight- inder up to the level of the outlet of the fitting stopper, and placed in an ice bath or condenser tube in a transparent bath main- refrigerator capable of bringing the gasoline tained between the temperatures of 32 and to a temperature of not less than 32°F (O'C), 34°F (O and 1.i"C) Cover the top of the nor more than 40°F (4.5"C) cylinder closely during the distillation with a piece of blotting paper, or its equivalent, so 7 Preparation of Apparatus cut as to fit the condenser tube tightly A lead washer, or other suitable material, resting on 7.1 Fill the condenser bath with cracked the blotting paper is a convenient accessory as ice (Note 2) and add enough water to cover it serves to hold the paper tightly against the the condenser tube Maintain the temperature top of the cylinder and also provides the addi- between 32 and 34°F (O and 1.1"C).Agitation tional weight necessary to overcome the buoy- with air gently aids in maintaining the re- ant effect of the liquid in the cooling bath quired temperature range 8 Procedure NOTE 2 -Any other convenient cooling medium 8.1 When everything is in readiness, apply may be used heat immediately at a uniform rate, so regu- lated that the first drop of the condensate falls 7.2 Swab the condenser tube to remove from the condenser in notless than 2 min nor any liquid remaining from the previous test A more than 5 min When the first drop falls piece of soft, lint-free cloth attached to a cord from the end of the condenser, move the re- or copper wire may be used for this purpose ceiving cylinder so that the end of the con- denser tube shall touch the side of the cylin- 7.3 Measure a 100-ml sample in the 100- der Then regulate the heat so that the first 10 ml graduated cylinder at 32 to 40°F (O to ml of distillate shall be recovered in not less 4.5"C) and transfer it directly to the distil1.a- than 3 min nor more than 4 min Thereafter, tion flask Both the flask and the graduated maintain the rate of distillation uniformly at cylinder shall have been cooled to a tempera- not less than 4 rnl/min nor more than 5 rnl/ ture of from 32 to 40°F (O to 4.5"C) before min Record the reading of the distillation use Do not permit any of the liquid to flow thermometer when the level of the distillate into the vapor tube 7.4 Make a record of the room tempera- ture at the time of each distillation The heat- ing apparatus including the shield and flask support shall be at room temperature at the start of each distillation 145 ~ 7009276 O O L 9 8 L 8 678 9 D 2 1 6 - @ 191 reaches each 10-ml mark on the cylinder I n rated at the temperature in question Make case a product is being tested to ascertain clear distinction between the inclusion or ex- clusion of the distillation loss figure in the whether or not it conforms with a given speci- report of the volume of distillate obtained at fication, make and record all necessary obser- a n y prescribed temperature In the first case vations, whether or not they are included in report the figure as the volume ewporared, in the second, as the volume recovered the series ordinarily employed by the labora- tory making the test 9 Correction of Temperature Points to Stan- dard Atmospheric Pressure 8.2 When the liquid residue in the distilla- tion flask is approximately 5 ml, the heat may 9.1 Ascertain and record the actual baro- be increased because of the presence of heavy metric pressure, but do not make any correc- ends which have relatively high boiling points tion except in case of dispute I n such cases However, do not apply any further increase of correct the temperature points to 760 mm heat after this adjustment T h e 4 to 5-ml rate (29.92 in.) Hg, by the use of the Slrdney cannot always be maintained from this point Young equation, as follows: to t h e end of the distillation, but in no case should the period between the point when For Celsius readirrgs: approximately 5 ml of the liquid remains i n the flask and the end point be more than 5 C, = 0.00012 (760 - P ) ( 2 7 3 + I , ) min For F d ireriheir readings: 8.3 Continue the heating until the mercury reaches a maximum and starts to fall consist- C, = 0.00012 (760 - P)(160 + I,) ently after the bottom of the flask has become dry Record the highest temperature observed where: on the distillation thermometer as the maxi- C, and C, = the correction to be added to the mum temperature or erid poirir observed temperature t, or I,, respec- 8 4 Observe the total volume of the distil- tively, and late collected in the receiving cylinder at the P = the actual barometric pressure, m m Hg conclusion of the distillation, and thereafter at I n case of dispute, however, no test shall be not less than ?-min intervals, until successive regarded as official when conducted under an observations agree Then record this volume absolute pressure lower than 735 mm (38.94 as the recover! in.) Hg 9.2 The following table is a convenient ap- 8.5 Pour the cooled residue from the flask proximation of the corrections as calculated by the above equation: into a small cylinder graduated in 0.1 ml, measure when cool, and record the volume as Temperature Range Correction"ll0-mm residrre at 32 to 40°F (O to 4.5"C) Difference in Pressure 8.6 Calculate the difference between 100 "C "F "C "F ml and the sum of the recovery and the resi- due and record as disrillariori loss 10 to 30 50 to 86 0.35 0.63 30 to 50 86 to 122 0.38 0.68 NOTE 3 -Abnormal distillation losses, when 50 to 70 122 to 158 0.40 0.77 caused by low barometric pressure, may be cor- 70 to 90 158 to 194 0.47 0.76 rected by the equation given below to an approxi- 90 to 110 194 to 230 0.45 0.81 mation of the loss to be expected under normal 110 to 130 230 to 266 0.47 0.85 pressure The corrected losses shall not be used in 130 to 150 266 to 302 0.50 0.89 the calculation of percentages evaporated 150 to 170 302 to 338 0.52 0.94 170 to 190 338 to 374 0.54 0.98 Corrected loss = A L + B 190 to 210 374 to 410 0.57 1 o2 210 to 230 410 to 446 0.59 1 O6 where: 230 to 250 446 to 482 0.62 1.11 250 to 270 482 to 518 0.61 1.15 L = observed distillation loss, 270 to 290 518 to 554 0.66 1.19 A and B = empirical constants, as given in Table 290 to 310 554 to 590 0.69 1 ?-I 1, for various values of t h e observed baromet- " To be added in case barometric pressure is below 760 ric pressure m m Hg (101.3 kPa); to be subtracted in case barometric 8.7 The sum of the volunie collected in the pressure is above 760 m m Hg (101.3 kPa) cylinder at any specified temperature, includ- ing the initial boilins point, and the distillation loss may be recorded as the percentage evapo- 146 Temperature Range Correction io-mm = 900927b O O l 9 8 ~ 95 0 4 Difference in Pressure D 2 1 6 - @ 191 "C "F "C "F 590 to 626 pressure and report that the correction has 310 to 330 626 to 662 0.71 1.28 been made Do not correct thermometer 330 to 350 662 to 698 readings for errors due to emergent stem 350 to 370 698 to 733 0.74 1.32 370 to 390 734 to 770 11 Precision 390 to 410 0.76 1.37 11.1 With proper care and strict attention 0.78 1.31 to details, duplicate results obtained for end point should not differ from each other by 0.81 1.45 more than 6°F (3.5"C) Differences in dupli- cate temperature readings for each prescribed 10 Report percentage point should not exceed the amounts equivalent to 2 ml of distillate at 10.1 Report the data recorded in Section 8 each point in question according to requirements, the room temper- ature, and the barometric pressure I n cases of dispute, correct for variations of barometric TABLE 1 Values of the Constants "A" and "B" Used in Obtaining Corrected Distillation Loss Observed A Observed A B Barometric Barometric Pressure 0.231 0.384 Pressure 0.375 0.312 0.240 0.380 0.400 0.300 mm HE 0.250 0.375 mm He 0.428 0.286 0.261 0.369 0.461 0.269 560 0.273 0.363 660 0.500 0.250 570 0.286 0.357 670 0.545 0.227 580 0.300 0.350 680 0.600 0.200 590 0.316 0.342 690 0.667 0.166 600 0.333 0.333 700 0.750 0.125 610 0.333 0.323 710 620 720 0.857 0.071 630 730 1.000 0.000 640 740 650 750 760 The American Society f o r Testing and Muterials takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard Users of this standard are expressiv advised that determination of the va1idit.v of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility This standard is subject to revision at any time b,v the responsible technical committee and must be reviewed every five ?ears and i f not revised, either reapproved or withdrawn Your comments are invited eitherfor revision of this standard orf o r additional standards and should be addressed to A S T M Headquarters Your comments will receive careful considerationat a meeting of the responsible technical commitlee which you ma-v attend I f youfeel thatyour comments have not received afair hearingyou should makeJour views known to the A S T M Committee on Standards, 1916 Race SI., Philadelphia, Pa 19103 147