ASTM D4085-93(2021)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D4085 − 93 (Reapproved 2021)
Standard Test Method for
Metals in Cellulose by Atomic Absorption
Spectrophotometry
This standard is issued under the fixed designation D4085; 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 3. Summary of Test Method
3.1 The sample is ashed in accordance with Test Methods
1.1 This test method covers the determination of the iron,
copper, manganese, and calcium content of cellulose pulp from D3516.
wood or cotton.
3.2 This test method is dependent on the fact that metallic
elements in the ground state will absorb light of the same
1.2 The values stated in SI units are to be regarded as
wavelength they emit when excited. When radiation from a
standard. No other units of measurement are included in this
given excited element is passed through a flame containing
standard.
ground-state atoms of that element, the intensity of the trans-
1.3 This standard does not purport to address all of the
mitted radiation will decrease in proportion to the amount of
safety concerns, if any, associated with its use. It is the
the ground-state element in the flame. A hollow cathode lamp
responsibility of the user of this standard to establish appro-
whose cathode is made of the element to be determined
priate safety, health, and environmental practices and deter-
provides the radiation. The metal atoms to be measured are
mine the applicability of regulatory limitations prior to use.
placed in the beam of radiation by aspirating the specimen into
1.4 This international standard was developed in accor-
an oxidant-fuel flame. A monochromator isolates the charac-
dance with internationally recognized principles on standard-
teristic radiation from the hollow cathode lamp and a photo-
ization established in the Decision on Principles for the
sensitive device measures the attenuated transmitted radiation.
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
4. Significance and Use
Barriers to Trade (TBT) Committee.
4.1 Manganese in pulp acts as a catalyst in oxidizing
cellulose.
2. Referenced Documents
4.2 Iron in pulp can cause yellowness in rayon fibers and
2.1 ASTM Standards:
influence cellulose acetate plastics color. Iron also causes
D1193 Specification for Reagent Water
problems in photographic and blueprint papers.
D1348 Test Methods for Moisture in Cellulose (Withdrawn
2017)
4.3 Copper in pulp can act as a retardant in oxidizing
D3516 Test Methods for Ashing Cellulose
cellulose and can affect viscose ripening. Copper interferes
E177 Practice for Use of the Terms Precision and Bias in
with the dye level of rayon fibers and influences cellulose
ASTM Test Methods
acetate plastics color.
E691 Practice for Conducting an Interlaboratory Study to
4.4 Calcium in pulps can cause problems in processing into
Determine the Precision of a Test Method
acetate, rayon, cellophane, etc. Calcium can create undesirable
deposits in viscose spinning and film casting operation. Cal-
cium can influence viscosity control during cellulose acetate
This test method is under the jurisdiction of ASTM Committee D01 on Paint
manufacture.
and Related Coatings, Materials, andApplications and is the direct responsibility of
Subcommittee D01.36 on Cellulose and Cellulose Derivatives.
5. Apparatus
Current edition approved July 1, 2021. Published August 2021. Originally
approved in 1981. Last previous edition approved in 2013 as D4085 – 93 (2013).
5.1 Atomic Absorption Spectrophotometer, consisting of an
DOI: 10.1520/D4085-93R21.
atomizer and burner, suitable pressure-regulating devices ca-
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
pable of maintaining constant oxidant and fuel pressure for the
Standards volume information, refer to the standard’s Document Summary page on
duration of the test, a hollow cathode lamp for each metal to be
the ASTM website.
tested, an optical system capable of isolating the desired line of
The last approved version of this historical standard is referenced on
www.astm.org. radiation, an adjustable slit, a photomultiplier tube or other
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D4085 − 93 (2021)
photosensitivedevice,andaread-outmechanismforindicating 6.8 Lanthanum Solution (50 g/L)—Wet 58.65 g of lantha-
the amount of absorbed radiation. num oxide (La O ) with water. Add slowly 250 mL of HCl to
2 3
the mixture. When dissolved dilute to 1 L with water.
5.2 Oxidant—Air, which has been cleaned and dried
through a suitable filter to remove oil, water, and other foreign
7. Preparation of the Sample
substances, is the usual oxidant.
7.1 Selectarepresentativesampleintheamountof30g,5 g
5.3 Fuel—Acetylene, commercially available, is the usual
for the determination of moisture and 25 g for the determina-
fuel. Acetone, always present in acetylene cylinders, can be
tion of the metals.
prevented from entering and damaging the burner head by
replacing a cylinder that has a gage pressure of only 3.5 kPa
8. Procedure
(50 psi) remaining.
8.1 Weigh about 25 g of pulp to the nearest 0.01 g. At the
5.4 Volumetric Flasks, 25-mL, 100-mL, and 1000-mL.
same time weigh out a separate sample for oven-dry cellulose
NOTE 1—In listing the apparatus for this method, the items required for
determination. Ash the sample by Method D in Test Methods
theashingsteparenotlisted.FortheseitemsrefertoTestMethodsD3516.
D3516. Determine moisture content in accordance with Test
Methods D1348.
6. Reagents
NOTE 3—Method D in Test Methods D3516 has been listed as the
6.1 Purity of Reagents—Reagent grade chemicals shall be
preferred one because it minimizes opportunity for sample loss during
used in all tests. Unless otherw
...