ASTM D4905-99(2004)

Standard Practice for Preparation of Solution of Solid, Pasty and Powdered Vegetable Tannin Extracts

SIGNIFICANCE AND USE
The concentration of tannins in solid, pasty, and powdered extracts needs to be reduced to analytical strength for tannin analyses.
4.2 Vegetable tannin extracts are heterogeneous mixtures of components with varying solubility.
4.3 The solubility of such extracts is influenced by temperature and concentration, which affect the degree of dispersion and size of the component particles.
4.4 Since extracts have greater solubility in hot water than cold, it is desirable to dissolve and disperse an extract in hot water and then let the solution cool slowly to standard room temperature.
It is often difficult to reduce samples of solid and particularly pasty extracts to specimen size and at the same time ensure representative sampling. Therefore, caution is advised in drawing conclusions on the precision and bias of the results obtained on such extracts; where difficulties in sample preparation are experienced, little confidence can be placed in the results.
SCOPE
1.1 This practice covers a standard procedure for use in preparing the analytical solution required for the analysis of solid, pasty, or powdered vegetable tannin extracts.
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-Mar-2004
• Technical Committee: D31 - Leather
• Drafting Committee: D31.01 - Vegetable Leather

Relations

• Replaces: ASTM D4905-99 - Standard Practice for Preparation of Solution of Solid, Pasty and Powdered Vegetable Tannin Extracts
• Effective Date: 01-Apr-2004
• Replaced By: ASTM D4905-99(2009) - Standard Practice for Preparation of Solution of Solid, Pasty and Powdered Vegetable Tannin Extracts
• Effective Date: 01-Apr-2009
• Referred By: ASTM D6409-99(2020) - Standard Practice for Color Tests with Sheepskin Skiver
• Effective Date: 01-Apr-2004
• Referred By: ASTM D4904-99(2020) - Standard Practice for Cooling of Analytical Solutions
• Effective Date: 01-Apr-2004
• Referred By: ASTM D6401-99(2020) - Standard Test Method for Determining Non-Tannins and Tannin in Extracts of Vegetable Tanning Materials
• Effective Date: 01-Apr-2004
• Referred By: ASTM D4900-99(2020) - Standard Test Method for Lignosulfonates (Sulfite Cellulose) in Tanning Extracts
• Effective Date: 01-Apr-2004
• Referred By: ASTM D4899-99(2020) - Standard Practice for Analysis of Vegetable Tanning Materials—General
• Effective Date: 01-Apr-2004
• Referred By: ASTM D6406-99(2020) - Standard Test Method for Analysis of Sugar in Vegetable Tanning Materials
• Effective Date: 01-Apr-2004
• Referred By: ASTM D6402-99(2020) - Standard Test Method for Determining Soluble Solids and Insolubles in Extracts of Vegetable Tanning Materials
• Effective Date: 01-Apr-2004
• Referred By: ASTM D4903-99(2020) - Standard Test Method for Total Solids and Water in Vegetable Tanning Material Extracts
• Effective Date: 01-Apr-2004

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:D4905–99(Reapproved2004)
Standard Practice for
Preparation of Solution of Solid, Pasty and Powdered
Vegetable Tannin Extracts
This standard is issued under the fixed designation D 4905; 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. Significance and Use
1.1 This practice covers a standard procedure for use in 4.1 The concentration of tannins in solid, pasty, and pow-
preparing the analytical solution required for the analysis of dered extracts needs to be reduced to analytical strength for
solid, pasty, or powdered vegetable tannin extracts. tannin analyses.
1.2 This standard does not purport to address all of the 4.2 Vegetable tannin extracts are heterogeneous mixtures of
safety concerns, if any, associated with its use. It is the components with varying solubility.
responsibility of the user of this standard to establish appro- 4.3 The solubility of such extracts is influenced by tempera-
priate safety and health practices and determine the applica- ture and concentration, which affect the degree of dispersion
bility of regulatory limitations prior to use. and size of the component particles.
4.4 Since extracts have greater solubility in hot water than
2. Referenced Documents
cold, it is desirable to dissolve and disperse an extract in hot
2.1 ASTM Standards: water and then let the solution cool slowly to standard room
D 4903 TestMethodforTotalSolidsandWaterinVegetable
temperature.
Tanning Material Extracts 4.5 It is often difficult to reduce samples of solid and
D 4904 Practice for Cooling of Analytical Solutions
particularly pasty extracts to specimen size and at the same
D 6403 Test Method for Determining Moisture in Raw and time ensure representative sampling. Therefore, caution is
Spent Materials
advised in drawing conclusions on the precision and bias of the
D 6404 Practice for Sampling of Vegetable Materials Con- results obtained on such extracts; where difficulties in sample
taining Tannin
preparation are experienced, little confidence can be placed in
2.2 ALCA Method:
the results.
A11 Preparation of Solution of Solid, Pasty, and Powdered
3 5. Specimen
Extracts
5.1 The specimen shall consist of a portion of the extract
3. Summary of Practice
sample, prepared as described in Practice D 6404 , sufficient to
3.1 This practice describes a procedure to follow in the
give a solution containing as nearly as possible 4 g of tannin
preparation of analytical strength solutions from samples of per L (not less than 3.75 g, nor more than 4.25 g, per L).
solid, pasty, and powdered vegetable tannin extracts.
6. Apparatus and Reagents
6.1 Formaldehyde—40 % solution.
6.2 Toluene—Assay$ 99.5 %.
ThispracticeisunderthejurisdictionofASTMCommitteeD31onLeatherand
6.3 Small Mortar and Pestle.
is the direct responsibility of Subcommittee D31.01 on Vegetable Leather. This
6.4 1-L Volumetric Flask, M.C.A. type, mixing bulb style.
practice has been adapted from and is a replacement for MethodA11 of the Official
Methods of the American Leather Chemists Association.
Current edition approved April 1, 2004. Published May 2004. Originally 7. Procedure
approved in 1989. Last previous edition approved in 1999 as D 4905–99.
2 7.1 Emptythesampleontoasheetofclean,glazedpaper(or
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
suitable clean, smooth foil material), roughly crush any large
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
lumps, and quickly mix and quarter the whole. From each
the ASTM website.
quarter, take a small representative portion, quickly crush,
Official Methods of the American Leather Chemists Association. Available
transfer to a small, glass stoppered weighing bottle, and take to
from the American Leather Chemists Association, University of Cincinnati, P.O.
Box 210014, Cincinnati, OH 45221–0014. the balance. Without delay, transfer the analy
...