ASTM E147-61(1996)

Standard Specification for Apparatus For Microdetermination Of Nitrogen By Kjeldahl Method

SCOPE
1.1 This specification covers digestion and distillation apparatus used for the microdetermination of nitrogen by the Kjeldahl method, and modifications thereof at atmospheric pressure.  
Note 1—This specification is based on those originally developed by the Committee on Microchemical Apparatus, Division of Analytical Chemistry, American Chemical Society.

General Information

• Status: Historical
• Publication Date: 17-Sep-1961
• Technical Committee: E41 - Laboratory Apparatus
• Drafting Committee: E41.01 - Laboratory Ware and Supplies

Relations

• Replaced By: ASTM E147-61(2001) - Standard Specification for Apparatus For Microdetermination Of Nitrogen By Kjeldahl Method
• Effective Date: 18-Sep-1961
• Referred By: ASTM E1377-99(2022) - Standard Specification for Laboratory Glass Kjeldahl Flasks
• Effective Date: 18-Sep-1961

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or discontinued.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: E 147 – 61 (Reapproved 1996)
Standard Specification for
Apparatus For Microdetermination Of Nitrogen By Kjeldahl
Method
This standard is issued under the fixed designation E 147; 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 parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
TABLE 1 Digestion Flasks
1. Scope
Capacity, mL Figure Use
1.1 This specification covers digestion and distillation ap-
10 1 with digests of 1 mL or less
paratus used for the microdetermination of nitrogen by the
30 2 with digests of 1 to 4 mL
Kjeldahl method, and modifications thereof at atmospheric
30 (Soltys) 3 with digests of 1 to 4 mL when
pressure.
danger of spattering is
great.
NOTE 1—This specification is based on those originally developed by
the Committee on Microchemical Apparatus, Division of Analytical
Chemistry, American Chemical Society.
support, and a fume duct. The rack shall be supplied with a heat
deflector mounted under the burners to prevent overheating of
2. Referenced Documents
the bench top.
2.1 ASTM Standards:
5.1.1 Heaters—The source of heat may be either electric or
E 124 Specification for Weighing and Drying Apparatus for
gas. In operation, each heater shall supply sufficient heat to a
Microchemical Analysis
30-mL flask to cause 15 mL of water at 25°C to come to a
rolling boil in not less than 2 or more than 3 min. A device shall
3. Tolerances
be provided for regulating the amount of heat supplied to the
3.1 The following commercial length tolerance shall be
flask so that these conditions can be met. The amount of heat
adhered to, unless otherwise specified:
supplied to the flasks also shall be so adjustable that low-
Up to 10 mm 61mm
temperature digestions are possible. Switches and controls
10 to 100 mm 62mm
100 to 200 mm 63mm
200 mm 64mm
4. Digestion Flasks
4.1 Digestion flasks of three types shall conform to the
requirements prescribed in Table 1 and Fig. 1, Fig. 2, and Fig.
3. The flasks shall be made of shock-resistant glass with linear
−7
coefficient of expansion not greater than 33.5 3 10 cm/cm
·°C.
NOTE 2—The weighing tubes described in Specification E 124 Figs. 12,
Figs. 13, and Figs. 14, are recommended for introducing solid samples
into the micro Kjeldahl digestion flasks. Combustion boats, Fig. 1 and Fig.
2 of Specification E 124, are recommended for use with waxy and
nonvolatile liquid samples.
5. Digestion Rack
5.1 The micro Kjeldahl digestion rack shall be portable and
shall consist of flask heaters (either gas or electric), a flask
This specification is under the jurisdiction of ASTM Committee E-41 on
Laboratory Apparatus and is the direct responsibility of Subcommittee E 41.07 on
Piston Operated Volumetric Apparatus (POVR).
Current edition approved Sept. 18, 1961. Published November 1961. Originally
published as E 147 – 59T. Last previous edition E 147 – 59T.
Committee on Microchemical Apparatus, “Recommended Specification for
Microchemical Apparatus, Micro Kjeldahl Nitrogen,” Analytical Chemistry, Vol 23,
1951, p. 523.
Annual Book of ASTM Standards, Vol 14.02. FIG. 1 10-mL Kjeldahl Flask
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
E 147
shall be conveniently located and shall remain cool enough to
handle even after long periods of operation.
NOTE 3—Boiling chips shall be added when testing the heaters to
minimize superheating, and the burners and rack shall be at equilibrium
temperature.
5.1.2 Flask Support—The support on which the bulbs of the
flasks rest shall shield the necks of the flasks from excessive
heating during digestion and shall be provided with circular
openings not exceeding 26 mm in diameter, centered over each
heater.
5.1.3 Fume Duct—The fume duct shall provide means for
adequately removing the fumes evolved during the digestion
and shall support the necks of the flasks at an angle greater than
35° to the horizontal. Fume ducts meeting these specifications
are shown in Fig. 4 and Fig. 5. The fume duct illustrated in Fig.
4 is supported and held in place by suitable clamps mounted at
either end of the digestion rack. The fume duct in Fig. 5 rests
upon a circular support plate and is held in place by springs
from the plate to the four glass hooks. The concav
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