ASTM D7967-16

Standard Test Method for Analysis of Chrome Content (as Cr<inf>2</inf>O<inf>3</inf>) in Wet Blue using Atomic Absorption

SIGNIFICANCE AND USE
5.1 The procedure described is for chromium in Wet Blue using Atomic Absorption. This method may be used to determine the chromium content in Wet Blue as an alternate to Test Method D6656.  
5.2 The chromium content of Wet Blue is related to the degree of tannage obtained, and hence may be a matter for specification in the purchase of Wet Blue. The procedure described provides adequate accuracy for this purpose.
SCOPE
1.1 This test method covers the Atomic Absorption procedure, using nitrous oxide-acetylene flame, to analyze the chrome content of Wet Blue on a moisture-free basis.  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Some specific hazards statements are given in Section 9 on Hazards and in 12.5.

General Information

• Status: Historical
• Publication Date: 31-Aug-2016
• ICS: 59.140.30 - Leather and furs
• Technical Committee: D31 - Leather
• Drafting Committee: D31.02 - Wet Blue

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D7967 − 16
Standard Test Method for
Analysis of Chrome Content (as Cr O ) in Wet Blue using
2 3
1
Atomic Absorption
This standard is issued under the fixed designation D7967; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope 4. Summary of Test Method
1.1 This test method covers the Atomic Absorption 4.1 ThechromiumcontentmeasuredasCr O isdetermined
2 3
procedure, using nitrous oxide-acetylene flame, to analyze the in Wet Blue using Atomic Absorption (AA). The Wet Blue is
chrome content of Wet Blue on a moisture-free basis. digested using oxalic acid, hydrochloric acid, and potassium
chloride. The chromium content in Wet Blue is measured at a
1.2 The values stated in SI units are to be regarded as
wavelength of 429 nanometers with a 0.7 slit using Atomic
standard. No other units of measurement are included in this
Absorption with a nitrous oxide/acetylene flame.After theAA
standard.
reading the chromium content is determined on a moisture-free
1.3 This standard does not purport to address all of the
basis.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
5. Significance and Use
priate safety and health practices and determine the applica-
5.1 The procedure described is for chromium in Wet Blue
bility of regulatory limitations prior to use. Some specific
using Atomic Absorption. This method may be used to deter-
hazards statements are given in Section 9 on Hazards and in
mine the chromium content in Wet Blue as an alternate to Test
12.5.
Method D6656.
2. Referenced Documents
5.2 The chromium content of Wet Blue is related to the
2
degree of tannage obtained, and hence may be a matter for
2.1 ASTM Standards:
specification in the purchase of Wet Blue. The procedure
D1517 Terminology Relating to Leather
described provides adequate accuracy for this purpose.
D6656 Test Method for Determination of Chromic Oxide in
Wet Blue (Perchloric Acid Oxidation)
6. Interferences
D6659 Practice for Sampling and Preparation of Wet Blue
and Wet White for Physical and Chemical Tests
6.1 The nitrous oxide/acetylene flame reduces or eliminates
D6658 Test Method for Volatile Matter (Moisture) of Wet
manychemicalorcompoundinterferencesthatcanoccurifjust
Blue by Oven Drying
an air/acetylene flame is used, however, sensitivity may be
E177 Practice for Use of the Terms Precision and Bias in
reduced.
ASTM Test Methods
E691 Practice for Conducting an Interlaboratory Study to
7. Apparatus
Determine the Precision of a Test Method
7.1 Atomic Absorption analyzer using a nitrous oxide-
acetylene flame measuring at a wavelength of 429 nanometers
3. Terminology
with a slit of 0.7 mm.
3.1 Definitions: For Definitions of general leather and tan-
NOTE 1—Follow manufacturer’s recommendations for using nitrous
ning terms used in this test method refer to Terminology
oxide-acetylene flame conditions.
D1517.
7.2 Analytical Balance, accurate and calibrated to 0.001 g.
7.3 Leather Cutting Tool, (such as scissors or razor blade).
1
This test method is under the jurisdiction ofASTM Committee D31 on Leather
7.4 Beaker, 250 mL capacity or equivalent.
and is the direct responsibility of Subcommittee D31.02 on Wet Blue.
7.5 Beaker, 1000 mL capacity or equivalent.
Current edition approved Sept. 1, 2016. Published October 2016. DOI: 10.1520/
D7967-16.
7.6 Volumetric Flask, 200 mL capacity or equivalent.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
7.7 Volumetric Flask, 1000 mL capacity or equivalent.
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. 7.8 Erlenmeyer Flask, 1 L capacity, or equivalent.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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D7967 − 16
7.9 Watch Glass. 8.11 Commercial Cr Standard, 1000 ppm:
8.11.1 Using a commercially available 1000 ppm Cr Stan-
7.10 Hot Plate, to be placed inside exhaust or fume hood.
dard solution, make a 10 ppm Cr solution which will be used
7.11 Desiccator.
to verify the concentration of the prepared Cr O standard in
2 3
8.12. To convert from Cr to Cr O , multiply by a factor of
2 3
8. Reagents and Materials
1.462 (A 10 ppm Cr solution equates to a 14.62 ppm Cr O
2 3
8.1 Purity of Reagents—Analytical Reagent (AR) Grade solution).
shall be used in all tests. Unless otherwise indicated, it is
8.12 Standard Cr O solution (1000 ppm):
2 3
intended that all rea
...