1、Designation: E191 64 (Reapproved 2017)Standard Specification forApparatus For Microdetermination of Carbon andHydrogen in Organic and Organo-Metallic Compounds1This standard is issued under the fixed designation E191; the number immediately following the designation indicates the year oforiginal ado
2、ption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defen
3、se.1. Scope1.1 This specification covers apparatus and basic equipmentfor the determination of carbon and hydrogen in organic andorganometallic compounds along the lines of the conventionalmethod of Pregl, but with modifications more in line withmodern practice. Owing to the diversity of apparatus b
4、y whichcorrect results can be obtained, this specification is intended toindicate what is acceptable rather than what is mandatory.NOTE 1Specifications for several items subsequently listed weredeveloped by the Committee for the Standardization of MicrochemicalApparatus, Division of Analytical Chemi
5、stry, American Chemical Soci-ety.21.2 The values stated in inch-pound units are to be regardedas the standard. The metric equivalents of inch-pound unitsmay be approximate.2. Referenced Documents2.1 ASTM Standards:3E124 Specification for Weighing and Drying Apparatus forMicrochemical AnalysisE148 Sp
6、ecification for Apparatus for Microdetermination ofNitrogen by the Dumas Method (Withdrawn 1987)43. Oxygen Supply3.1 Any cylinder or other suitable source of oxygen free ofhydrogen and organic impurities may be used. Oxygen pre-pared from liquid air is satisfactory.4. Pressure Regulator4.1 The press
7、ure regulator, shown in Fig. 1 and Fig. 2,5consisting of a bell and inlet tube submerged in a suitableconfining liquid, shall be used to supply air or oxygen, or both,at constant pressure to the combustion system. Substitution ofa fine gas-control valve and flowmeter for the pressure regu-lator is o
8、ptional.5. Drying and Purifying Tube25.1 The conventional bubble-container U-tube shown inFig. 3 shall be used for drying and purifying the entering air oroxygen, or both.6. Flowmeter6.1 The rate of gas flow shall be determined by the bubblecounter of the bubble-counter U-tube, or by a more accurate
9、flow-meter, such as the floating ball-in-column.67. Combustion Unit7.1 The combustion unit shall consist of a long furnace, asample furnace, a constant-temperature heating mortar, acombustion tube, and a combustion-tube closure.7.1.1 Long Furnace:7.1.1.1 The long furnace shall have a maximum over-al
10、llength of 8 in. (203 mm) with the wall thickness at the ends notto exceed14 in. (6 mm). The furnace shall accommodatecombustion tubes up to 13 mm in outside diameter. Electricheating elements shall be easily replaceable. The furnace shallbe mounted firmly on a substantial support.7.1.1.2 The furnac
11、e shall be capable of continuous operationat temperatures up to 900C as measured inside the combustiontube at the middle of the furnace. The temperature drop fromthe center to points 1 in. (25 mm) and 134 in. (45 mm) fromeither end shall not exceed 15 and 7 %, respectively, based1This specification
12、is under the jurisdiction of ASTM Committee E41 onLaboratory Apparatus and is the direct responsibility of Subcommittee E41.01 onLaboratory Ware and Supplies.Current edition approved Jan. 1, 2017. Published February 2017. Originallyapproved in 1962. Discontinued in 1988 and reinstated in 1989. Last
13、previousedition approved in 2011 as E191 64 (2011). DOI: 10.1520/E0191-64R17.2Committee for the Standardization of Microchemical Apparatus. Division ofAnalytical Chemistry, American Chemistry Society, 1949 Report on RecommendedSpecifications for Microchemical Apparatus, Carbon-Hydrogen, Dumas Nitrog
14、en,Sulfur, and Halogen, Analytical Chemistry Vol 21, p. 1555 (1949).3For 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 the standards Document Summary page onthe ASTM w
15、ebsite.4The last approved version of this historical standard is referenced onwww.astm.org.5Furter, M. F., and Steyermark, A., “Pressure Regulator for Use in Microdeter-mination of Carbon and Hydrogen,” Analytical Chemistry, Vol 20, 1948, p. 257.6Kuck, J. A., and Altieri, P. L., “Spherical Ground-Gl
16、ass Joints vs. RubberTubing Connectors on the C and H Absorption Train,” Mikrochimica Acta,1956,p.1556.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recogni
17、zed principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1upon the temperature in the middle of the furnace.7Meansshall be p
18、rovided for varying the temperature.7.1.1.3 The furnace shall be equipped with some device forindicating the temperature at the middle of the furnace.7.1.2 Sample Furnace, Traveling Type (Note 2):7.1.2.1 The sample furnace shall have an over-all length notless than 212 in. (64 mm) nor more than 4 in
19、. (102 mm) withwall thickness at the ends not to exceed14 in. (6 mm). Thefurnace shall accommodate combustion tubes up to 13 mm inoutside diameter. Electric heating elements shall be easilyreplaceable. The furnace shall be mounted firmly on a substan-tial support.7.1.2.2 The sample furnace shall be
20、capable of continuousoperation up to 900C as measured inside the combustion tubeat the middle of the furnace. The temperature drop from thecenter to points34 in. (19 mm) from either end shall not exceed17 % of the temperature at the middle of the furnace.6Meansshall be provided for varying the tempe
21、rature.7.1.2.3 The sample furnace shall be designed so that it maybe either moved away from the combustion tube or turned offand cooled rapidly. In the latter case, the time for cooling toroom temperature and reheating to operating temperature shallnot exceed 30 min.7.1.2.4 The sample furnace shall
22、be equipped with somedevice for indicating the temperature at the middle of thefurnace.7.1.2.5 If the furnace is moved mechanically, it shall travela minimum distance of 614 in. (159 mm) with provision formanual setting at any point. Whether the furnace has only oneor more than one speed of movement
23、 over this distance, therates of travel shall be within the limits of18 to58 in. (3 to 16mm)/min. An automatic control shall be provided to stop thetravel of the sample furnace when it reaches the long furnace.NOTE 2The stationary multiple-section type of sample furnace maybe used instead of the tra
24、veling type, which differs from the traveling typeas follows: It consists of not less than three sections with a maximumlength of 7 in. (178 mm) and a maximum wall thickness of14 in. (6 mm)at the ends of any section. Each section shall be provided with itsindividual adjustable time switch, which can
25、 be set to go on or offautomatically for any time from 0 to 30 min. Provision shall be made forat least two sequences of heating of the various sections. Each section,when operated alone, shall be capable of continuous operation at tem-peratures up to 900C as measured inside the combustion tube at t
26、hemiddle of the section.7.1.3 Heating MortarAny type of heating mortar2may beused provided it is capable of maintaining constant temperatureto within 61C in the range from 175 to 190C. If electric, theelements shall be easily replaceable. It shall accommodatecombustion tubes of 13 mm in outside diam
27、eter. Means shallbe provided for heat transfer to the inlet capillaries of the waterabsorption tube to prevent condensation of water.7.1.4 Combustion TubeThe combustion tube shall have atip and side arm. Depending upon the length of furnaceassembly used, the tube shall be either as specified in Fig.
28、 4 ofSpecification E148 with a body length of 520 to 530 min,2orof similar construction with a body length of 620 to 630 mm.7.1.5 Combustion Tube ClosureA solid stopper of rubberor suitable substitute, such as cork, neoprene, etc., withdimensions as specified in Fig. 5 of Specification E148, shallbe
29、 used.7Several types of commercially available electric furnaces meet these require-ments.FIG. 1 Pressure Regulator, Glass PartsE191 64 (2017)28. Absorption Tubes28.1 Absorption tubes, preferably of soda-lime glass, shall beused. Two suitable sizes are shown in Fig. 4.9. Guard Tube29.1 The guard tub
30、e shall be as shown in Fig. 5.10. Mariotte Bottle210.1 A Mariotte bottle, as shown in Fig. 6, shall be usedwith the pressure regulator described in Section 4.11. Weighing Accessories11.1 Weighing accessories needed in the microdetermina-tion of carbon and hydrogen are described in SpecificationE124.
31、12. Keywords12.1 carbon; compounds; hydrogen; microdeterminationFIG. 2 Pressure Regulator, Details of ConstructionE191 64 (2017)3FIG. 3 Drying and Purifying TubeFIG. 4 Absorption TubeE191 64 (2017)4FIG. 5 Guard TubeFIG. 6 Mariotte BottleE191 64 (2017)5ASTM International takes no position respecting
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35、 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). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 64 (2017)6
