ASTM D6716-06

Standard Test Method for Total Ash in Wet Blue

SIGNIFICANCE AND USE
This test method is useful in determining the approximate amount of nonvolatile inorganic material in wet blue. This may be in the form of salts or oxides of the elements. In a mixed-chrome tannage, the approximate percentage of other elements in the wet blue may be determined by subtracting the chromic oxide that may be conveniently determined on the ash. (See Test Method D 6714.)
The specified temperature of 600°C is high enough to produce a reproducible result but it does not completely dehydrate such oxides as aluminum oxide (Al2O3) and chromic oxide (Cr2O3). Likewise, such salts as sulfates and phosphates may be incompletely dehydrated, and if alkalis and chromium are present simultaneously, oxidation to chromate may occur. Therefore, caution is advised in drawing conclusions based on quantitative relations of the elements.
SCOPE
1.1 This test method covers the determination of total ash in wet blue.
1.2 Total ash in wet blue may be reported upon a number of different bases (for example, fat-free, moisture-free, as received, excluding chromium, and so forth). Before proceeding with any tests, it is very important to determine upon which basis that the total ash is to be reported and to identify all other test methods that will be required to be executed in order to achieve the determined reporting method.
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.

General Information

• Status: Historical
• Publication Date: 30-Sep-2006
• ICS: 17.060 - Measurement of volume, mass, density, viscosity
• Technical Committee: D31 - Leather
• Drafting Committee: D31.02 - Wet Blue

Relations

• Replaces: ASTM D6716-01 - Standard Test Method for Total Ash in Wet Blue
• Effective Date: 01-Oct-2006
• Replaced By: ASTM D6716-08 - Standard Test Method for Total Ash in Wet Blue
• Effective Date: 01-Nov-2008
• Referred By: ASTM D6714-16(2021) - Standard Test Method for Chromic Oxide in Ashed Wet Blue (Perchloric Acid Oxidation)
• Effective Date: 01-Oct-2006

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D6716–06
Standard Test Method for
1
Total Ash in Wet Blue
This standard is issued under the fixed designation D 6716; 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.
1. Scope 4. Summary of Test Method
1.1 This test method covers the determination of total ash in 4.1 Theweighedsampleisignitedinairat600 625°Cuntil
wet blue. constant mass is attained. The weighed residual matter is
1.2 Total ash in wet blue may be reported upon a number of termed “ash” and is calculated as a percentage of the original
different bases (for example, fat-free, moisture-free, as re- sample.
ceived, excluding chromium, and so forth). Before proceeding
5. Significance and Use
with any tests, it is very important to determine upon which
basis that the total ash is to be reported and to identify all other 5.1 This test method is useful in determining the approxi-
mate amount of nonvolatile inorganic material in wet blue.
test methods that will be required to be executed in order to
achieve the determined reporting method. This may be in the form of salts or oxides of the elements. In
a mixed-chrome tannage, the approximate percentage of other
1.3 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the elements in the wet blue may be determined by subtracting the
chromicoxidethatmaybeconvenientlydeterminedontheash.
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica- (See Test Method D 6714.)
5.2 The specified temperature of 600°C is high enough to
bility of regulatory limitations prior to use.
produce a reproducible result but it does not completely
2. Referenced Documents
dehydratesuchoxidesasaluminumoxide(Al O )andchromic
2 3
2
2.1 ASTM Standards: oxide (Cr O ). Likewise, such salts as sulfates and phosphates
2 3
D 3495 Test Method for Hexane Extraction of Leather may be incompletely dehydrated, and if alkalis and chromium
D 6658 Test Method for Volatile Matter (Moisture) of Wet are present simultaneously, oxidation to chromate may occur.
Blue by Oven Drying Therefore, caution is advised in drawing conclusions based on
D 6659 Practice for Sampling and Preparation of Wet Blue quantitative relations of the elements.
for Physical and Chemical Tests
6. Apparatus
D 6714 Test Method for Chromic Oxide inAshed Wet Blue
6.1 Crucible, 30- to 50-mL, high-form, platinum or porce-
(Perchloric Acid Oxidation)
lain.
3. Terminology
6.2 Electric Muffle Furnace, with controller or rheostat and
3.1 Definitions: pyrometer, capable of maintaining a temperature of 600 6
3.1.1 The terms and definitions employed within this test 25°C.
method are commonly used in normal laboratory practice and 6.3 Dessicator, of appropriate size and charged with fresh
require no special comment. dessicant.
6.4 Analytical Balance, capable of accurate weighings to
within 0.001 g.
1
This test method is under the jurisdiction ofASTM Committee D31 on Leather
and is the direct responsibility of Subcommittee D31.02 on Blue Stock.
7. Test Specimen
Current edition approved Oct. 1, 2006. Published November 2006. Originally
approved in 2001. Last previous edition approved in 2001 as D 6716 – 01.
7.1 The specimen shall consist of 2 to 10 g of wet blue from
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
the composite sample, prepared in accordance with Practice
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
D 6659.
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
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D6716–06
NOTE 1—Typically,wetblueisacombinationoforganichidesubstance paper. Transfer the paper and insoluble residue to the crucible and ignite
in conjunction with inorganic chromium tanning salts. However, under at 600 6 25°C as described above. Cool, add the filtrate to the crucible,
some circumstances, silicones or other solvent-soluble organo-metallic evaporate carefully to dryness, then ignite at 600 6 25°C to constant mass
complexes (including electrolyte-stable fat liquors) are added during as described previously.
manufacture and may be present within the sample. It may be desirable to
9. Calculation
calculate ash upon an extracted (fat free) basis, and if so, this should be
indicated within the final report. To report ash upon an extracted basis, it
9.1 Calculate the percentage of ash in the wet blue
...