ASTM D6658-08

Standard Test Method for Volatile Matter (Moisture) of Wet Blue by Oven Drying

SIGNIFICANCE AND USE
The result obtained by this test is normally considered to be the moisture content of the wet blue or wet white sample. This result is used to correct all other chemical tests to a moisture-free basis.
Materials that are volatile under these conditions, other than water, may be present in the wet blue, although their amount in any normal wet blue would be expected to be a very small percentage of the total volatile matter.
Under the conditions of this test, certain materials in wet blue, such as protein fiber and chromium tanning salts, may retain moisture. Other materials, such as natural animal fats, may be oxidized. Both of these effects produce negative errors in the moisture determination.
The amount of volatile matter (moisture) released by a given sample varies with (a) method and time of sample preparation, (b) weight of sample taken, (c) temperature and time of the oven drying, (d) type of oven (gravity versus mechanical convection) used.
Because of the above unknown errors, the result of this test is a purely arbitrary value for the moisture content of the sample. It is, therefore, essential that the method be followed exactly in order to obtain reproducible results among laboratories. This is particularly true if other chemical analytical tests being performed on the same sample are reported on the moisture-free basis.
SCOPE
1.1 This test method covers the determination of volatile matter (moisture) in all types of wet blue and wet white.  
1.2 This test method was originally developed for wet blue, however, this test method can be used to test wet white. For wet white testing, substitute the term wet white for wet blue in the standard.  
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 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: 31-Oct-2008
• ICS: 59.140.10 - Processes and auxiliary materials
• Technical Committee: D31 - Leather
• Drafting Committee: D31.02 - Wet Blue

Relations

• Replaces: ASTM D6658-01(2006) - Standard Test Method for Volatile Matter (Moisture) of Wet Blue by Oven Drying
• Effective Date: 01-Nov-2008
• Replaced By: ASTM D6658-08(2013) - Standard Test Method for Volatile Matter (Moisture) of Wet Blue by Oven Drying
• Effective Date: 01-May-2013
• Referred By: ASTM D8451-22 - Standard Test Method for Calculation of Unfixed Chrome Concentration in Wet Blue
• Effective Date: 01-Nov-2008
• Referred By: ASTM D6716-08(2020) - Standard Test Method for Total Ash in Wet Blue or Wet White
• Effective Date: 01-Nov-2008
• Referred By: ASTM D6659-16(2021) - Standard Practice for Sampling and Preparation of Wet Blue and Wet White for Physical and Chemical Tests
• Effective Date: 01-Nov-2008
• Referred By: ASTM D7967-21 - Standard Test Method for Analysis of Chrome Content (as Cr<inf>2</inf>O<inf>3</inf>) in Wet Blue using Atomic Absorption or ICP
• Effective Date: 01-Nov-2008
• Referred By: ASTM D6656-16(2021) - Standard Test Method for Determination of Chromic Oxide in Wet Blue (Perchloric Acid Oxidation)
• Effective Date: 01-Nov-2008
• Referred By: ASTM D7674-14a(2021) - Standard Test Method for Hexane/Petroleum Ether Extract in Wet Blue and Wet White
• 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-Nov-2008

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: D6658 − 08
StandardTest Method for
1
Volatile Matter (Moisture) of Wet Blue by Oven Drying
This standard is issued under the fixed designation D6658; 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 amount in any normal wet blue would be expected to be a very
small percentage of the total volatile matter.
1.1 This test method covers the determination of volatile
matter (moisture) in all types of wet blue and wet white. 4.3 Under the conditions of this test, certain materials in wet
blue, such as protein fiber and chromium tanning salts, may
1.2 This test method was originally developed for wet blue,
retain moisture. Other materials, such as natural animal fats,
however,thistestmethodcanbeusedtotestwetwhite.Forwet
may be oxidized. Both of these effects produce negative errors
white testing, substitute the term wet white for wet blue in the
in the moisture determination.
standard.
4.4 The amount of volatile matter (moisture) released by a
1.3 The values stated in SI units are to be regarded as
given sample varies with (a) method and time of sample
standard. No other units of measurement are included in this
preparation, (b) weight of sample taken, (c) temperature and
standard.
time of the oven drying, (d) type of oven (gravity versus
1.4 This standard does not purport to address all of the
mechanical convection) used.
safety concerns, if any, associated with its use. It is the
4.5 Because of the above unknown errors, the result of this
responsibility of the user of this standard to establish appro-
test is a purely arbitrary value for the moisture content of the
priate safety and health practices and determine the applica-
sample. It is, therefore, essential that the method be followed
bility of regulatory limitations prior to use.
exactly in order to obtain reproducible results among labora-
2. Referenced Documents
tories.This is particularly true if other chemical analytical tests
2
being performed on the same sample are reported on the
2.1 ASTM Standards:
moisture-free basis.
D6659 Practice for Sampling and Preparation of Wet Blue
for Physical and Chemical Tests
5. Apparatus
3. Summary of Test Method
5.1 Appropriately sized weighing container with cover suit-
3.1 The prepared wet blue or wet white specimen is heated able for oven use.
in a forced air oven for 8 to 24 h at 100-105 °C, placed in a
5.2 Oven, forced air capable of attaining a steady 100-105
desiccator, cooled, and reweighed. The loss in weight repre-
°C, with a thermoregulator system. A thermometer accurate to
sents the volatile matter.
1 °C should be used to check and monitor the oven set point.
4. Significance and Use 5.3 Balance, capable of weighing up to 100 g with an
accuracy of 6 0.001 g.
4.1 Theresultobtainedbythistestisnormallyconsideredto
be the moisture content of the wet blue or wet white sample. 5.4 Desiccator, any convenient form or size, using any
This result is used to correct all other chemical tests to a normal desiccating agent such as calcium sulfate, calcium
moisture-free basis. chloride, or silica gel.
4.2 Materials that are volatile under these conditions, other
6. Sampling
than water, may be present in the wet blue, although their
6.1 TheleathershallbesampledinaccordancewithPractice
D6659.
1
This test method is under the jurisdiction ofASTM Committee D31 on Leather
and is the direct responsibility of Subcommittee D31.02 on Wet Blue.
Current edition approved Nov. 1, 2008. Published December 2008. Originally 7. Procedure
approved in 2001. Last previous edition approved in 2006 as D6658 - 01(2006).
7.1 Insert the empty weighing container and cover in the
DOI: 10.1520/D6658-08.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or oven at 100-105 °C for1hor more to insure dryness.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
7.2 Remove the container and cover from the oven and
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. place in a desiccator and cool to ambient temperature.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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D6658 − 08
7.3 Weigh the container and cover and record to the nearest
B = weight, grams, of empty covered container, and
6 0.001 g.
D = weight, grams, of oven-dried sample plus covered
container.
7.4 Transfer 10-15 g of wet blue prepared as specified in
D6659 into the previously weighed container.
9. Report
7.5 Weigh the covered container to the nearest
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation:D6658–01(Reapproved 2006) Designation:D6658–08
Standard Test Method for
1
Volatile Matter (Moisture) of Wet Blue by Oven Drying
This standard is issued under the fixed designation D 6658; 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
1.1This test method covers the determination of volatile matter (moisture) in all types of wet blue.
1.2
1.1 This test method covers the determination of volatile matter (moisture) in all types of wet blue and wet white.
1.2 This test method was originally developed for wet blue, however, this test method can be used to test wet white. For wet
white testing, substitute the term wet white for wet blue in the standard.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 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.
2. Referenced Documents
2
2.1 ASTM Standards:
D 6659 Practice for Sampling and Preparation of Wet Blue for Physical and Chemical Tests
3. Summary of Test Method
3.1 The prepared wet blue or wet white specimen is heated in a forced air oven for 8 to 24 h at 100-105 °C, placed in a
desiccator, cooled, and reweighed. The loss in weight represents the volatile matter.
4. Significance and Use
4.1 The result obtained by this test is normally considered to be the moisture content of the wet blue or wet white sample. This
result is used to correct all other chemical tests to a moisture-free basis.
4.2 Materials that are volatile under these conditions, other than water, may be present in the wet blue, although their amount
in any normal wet blue would be expected to be a very small percentage of the total volatile matter.
4.3 Under the conditions of this test, certain materials in wet blue, such as protein fiber and chromium tanning salts, may retain
moisture. Other materials, such as natural animal fats, may be oxidized. Both of these effects produce negative errors in the
moisture determination.
4.4 The amount of volatile matter (moisture) released by a given sample varies with (a) method and time of sample preparation,
(b) weight of sample taken, (c) temperature and time of the oven drying, (d) type of oven (gravity versus mechanical convection)
used.
4.5 Becauseoftheaboveunknownerrors,theresultofthistestisapurelyarbitraryvalueforthemoisturecontentofthesample.
It is, therefore, essential that the method be followed exactly in order to obtain reproducible results among laboratories. This is
particularly true if other chemical analytical tests being performed on the same sample are reported on the moisture-free basis.
5. Apparatus
5.1 Appropriately sized weighing container with cover suitable for oven use.
5.2 Oven, forced air capable of attaining a steady 100-105 °C, with a thermoregulator system.Athermometer accurate to 1 °C
should be used to check and monitor the oven set point.
5.3 Balance, capable of weighing up to 100 g with an accuracy of 6 0.001 g.
5.4 Desiccator, any convenient form or size, using any normal desiccating agent such as calcium sulfate, calcium chloride, or
silica gel.
1
This test method is under the jurisdiction of ASTM Committee D31 on Leather and is the direct responsibility of Subcommittee D31.02 on Blue Stock.Wet Blue.
Current edition approved Oct.Nov. 1, 2006.2008. Published November 2006.December 2008. Originally approved in 2001. Last previous edition approved in 20012006
as D 6658 - 01(2006).
2
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at [e-mail]. For Annual Book ofASTM 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.
1

---------------------- Page: 1 ----------------------
D6658–08
6. Sampling
6.1 The leather shall be sampled in accordance with Practice D 6659.
7. Procedure
7.1 Insert the empty weighing container and cover in the oven at 100-105 °C for1hor more to insure dryness.
7.2 Remove the contain
...