ASTM D1348-94(2008)
(Test Method)Standard Test Methods for Moisture in Cellulose (Withdrawn 2017)
Standard Test Methods for Moisture in Cellulose (Withdrawn 2017)
SIGNIFICANCE AND USE
These test methods determine the amount of moisture contained in a cellulose sample which determines the amount of bone dry cellulose present in a sample. The actual amount of cellulose in a sample is an essential entity when using cellulose as a starting material for the production of cellulose derivatives.
SCOPE
1.1 These test methods cover the determination of moisture in cellulose using two oven-drying procedures and one Karl Fischer procedure.
1.2 The test procedures appear in the following order:
Sections Test Method A—Specimen Weighed in Oven4-10 Test Method B—Specimen Weighed Outside of Oven11-17 Test Method C—Karl Fischer Method18-25
1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
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.
WITHDRAWN RATIONALE
Formerly under the jurisdiction of Committee D01 on Paint and Related Coating, Materials, and Applications, this test method was withdrawn in January 2017 in accordance with section 10.6.3 of the Regulations Governing ASTM Technical Committees, which requires that standards shall be updated by the end of the eighth year since the last approval date.
General Information
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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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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: D1348 − 94 (Reapproved 2008)
Standard Test Methods for
Moisture in Cellulose
This standard is issued under the fixed designation D1348; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope different moisture content in sections lying relatively close
together. In order to secure representative samples, therefore, a
1.1 These test methods cover the determination of moisture
bulk sample should be made up of small portions taken from
in cellulose using two oven-drying procedures and one Karl
various parts of the lot and having the proper proportion of
Fischer procedure.
edge and center material.
1.2 The test procedures appear in the following order:
3.1.2 Except for those samples taken in an atmosphere with
Sections
which the sample is in equilibrium, the moisture content of the
Test Method A—Specimen Weighed in Oven 4–10
Test Method B—Specimen Weighed Outside of Oven 11–17
sample will begin to change immediately after it is removed
Test Method C—Karl Fischer Method 18–25
from its original surroundings. This change can be reduced by
1.3 The values stated in SI units are to be regarded as the
taking extra layers of sheeted material and discarding a few
standard. The values given in parentheses are for information
layers from the top and bottom before weighing, folding, or
only.
rolling the sample to reduce the exposed area, and by placing
1.4 This standard does not purport to address all of the small samples in cans or bottles and protecting larger samples
safety concerns, if any, associated with its use. It is the by wrapping in rubber sheets, moistureproof cellophane, or
responsibility of the user of this standard to establish appro-
other protective wrappings. These means do not provide
priate safety and health practices and determine the applica-
continuous protection, and the test samples should be weighed
bility of regulatory limitations prior to use.
as soon as possible.
3.1.3 When possible, bulk samples should be taken. These
2. Significance and Use
samples should weigh from 100 to 300 g (3.5 to 10.5 oz), the
2.1 These test methods determine the amount of moisture
largersamplesbeingtakenwhenthemoisturecontentislowor
contained in a cellulose sample which determines the amount
variable. Following the initial weighing, the bulk samples
ofbonedrycellulosepresentinasample.Theactualamountof
should be cut up or torn into small pieces and then mixed and
celluloseinasampleisanessentialentitywhenusingcellulose
allowed to stand overnight or longer in a sealed container to
as a starting material for the production of cellulose deriva-
obtain moisture equilibrium before weighing out test speci-
tives.
mens; or the sample may be allowed to come to approximate
equilibriumwiththelaboratoryairandreweighedtodetermine
3. Sampling
moisture change before weighing test specimens. The latter
3.1 Cellulose in a variety of forms is sampled for moisture,
procedureisrecommendedsinceitpermitsroutineweighingof
and no single set of directions can be given that is applicable
samples without the use of special weighing bottles or boxes,
to all types of cellulose material. The following general
and a series of accumulated samples can be weighed simulta-
considerations should be borne in mind.
neously. Predrying is very desirable on samples with a high
3.1.1 Cellulose, either in compact form, such as wood,
moisture content (more than 5% above equilibrium value).
sheeted pulp or paper, baled cotton or baled staple rayon, or in
When samples have been predried, calculate the moisture lost,
loose form such as sawdust or chips, may have an appreciably
as follows:
R 5 M 2 A/A 3100 (1)
@ #
These test methods are under the jurisdiction of ASTM Committee D01 on
Paint and Related Coatings, Materials, and Applications and are the direct
where:
responsibility of Subcommittee D01.36 on Cellulose and Cellulose Derivatives.
Current edition approved June 1, 2008. Published June 2008. Originally
R = moisture, air-dry sample basis, %,
approved in 1954. Last previous edition approved in 2003 as D1348–94(2003).
M = original mass of the sample, g, and
DOI: 10.1520/D1348-94R08.
Copyright ©ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA19428-2959. United States
D1348 − 94 (2008)
weighedtothenearest0.005g.Designatethismassas M.Place
A = air-dry mass of sample, g.
the specimen in a tared container in the oven in such a manner
3.1.4 The apparent moisture subsequently observed when
that it can be reweighed without removal from the oven.
testingapredriedsamplemustbecalculatedonthebasisofthe
original sample mass in order to get the original moisture NOTE3—Experiencehasshownthatwhenyarnandfiberspecimensare
left in comparatively deep weighing bottles in the oven, relatively
content. Calculate the original mass of the air-dried sample as
discordantresultsareobtainedandthedryingperiodisunnecessarilylong.
follows:
To avoid these difficulties specimens should be dried in containers that
Originalsamplemass, g 5 A 3 1001R /100 (2) give the cellulose free access to the air. For fibrous or bulky materials to
@ ~ !#
be weighed in an oven, use containers such as open wire grills or baskets.
NOTE1—Example—If1000g(35oz)ofbulk(wet)sampleonexposure
For small specimens to be weighed out of the oven, use wire screen
toairlose200g(7oz)ofwater,theapparentmoisturecontentis20%and
baskets that will fit in weighing bottles, but if the specimen is powdery or
equivalent regain is 25%. If an 8-g (0.28-oz) specimen of the air-dry
tends to shed lint or fine short fibers, use a small weighing bottle or metal
material is taken for drying in the oven, the original mass is 8×1.25=10
boxes.
g (0.35 oz).
7.2 Dry the specimen for 2 h at 105 6 3°C, passing a
TEST METHOD A—SPECIMEN WEIGHED IN OVEN
current of dry air into the bottom of the oven during the drying
period. (If dry air is not forced through the oven, dry for 4 h.)
4. Scope
4.1 This test method for moisture determination is appli- NOTE 4—Reproducible but less accurate values (under unfavorable
conditionstheabsoluteerrormaybeashighas1%)willbeobtainedifthe
cable to a variety of cellulose types and can be used in most
current of predried air is omitted. Since the error will be identical for all
cases where a sample does not contain nonaqueous material
similarsamplesintheovenatonetime,theresultsobtainedinthesecases
volatile at 105°C. The test method can be used for samples
will be comparable. The magnitude of error will vary directly with the
having either high or low moisture content.
relative humidity of the air entering the oven and with the equilibrium
moisture content of samples at low relative humidity. Thus, the error will
behigheronregeneratedcellulosethanonwoodpulporcotton,butitstill
5. Summary of Test Method
would not usually be greater than 0.2%, absolute.
5.1 The specimen is heated to constant mass at 105°C in a
7.3 At the end of the specified period, cut off the flow of air
ventilated gravity-convection oven, in a current of dry air, for
and weigh the specimen without removing it from the oven.
a period of 2 h. If no dry air is used, the specimen is heated for
Continue drying for ⁄2 h longer, with the normal air flow, and
4h.
reweigh the specimen. Repeat the drying and weighing until
the mass loss between successive weighings is not more than
6. Apparatus
0.005 g, or until the specimen shows a gain in mass. Designate
6.1 Oven with Built-In Weighing Equipment—Such an oven
this mass as D.
employs a system of tared containers mounted on a table or
7.4 Additional specimens should not be placed in the oven
track that can be rotated to bring specimens to a specific point
until the first specimens have attained constant mass.
intheoven,wherethespecimenandcontainercanbeplacedon
a hook or a tray connected to an outside balance. The oven
8. Calculation
must be capable of maintaining a constant temperature of 105
6 3°C, with an average temperature of 105°C; continuous
8.1 Calculatemoisture,asmeasuredintheoven,asfollows:
operation below 105°C is not satisfactory.
Moisturecontent, % 5 M 2 D /M 3100 (3)
@~ ! #
NOTE 2—In ovens having heating elements at the bottom only, and no
Moisture, drybasis regain,% 5 M 2 D /D 3100 (4)
~ ! @~ ! #
cross circulation, the temperature of the lower shelves should be checked
before they are used.
where:
6.2 Dry Air Stream—Air, dried by passing through silica
M = original mass of specimen, and
gel, aluminum oxide, concentrated sulfuric acid, or other
D = mass of oven-dry specimen.
suitable drying agent, should be passed through the oven at a
rate sufficient to effect a complete change once every 2 min. If
9. Report
the air is dried by means of concentrated sulfuric acid,
9.1 Report the moisture in the cellulose on either or both of
adequate traps must be provided. The use of sulfuric acid
the following bases:
followed by perchloric drying agents should be avoided.
9.1.1 On the basis of the original sample, when it is termed
6.3 Shallow Glass Weighing Bottles—Bottles with ground
“moisture content,” “moisture as received,” or “moisture as is”
glass stoppers, measuring 30 mm high, and having a capacity
basis.
of 30 mL.
9.1.2 On the basis of the oven-dry cellulose, when it is
6.4 Seamless Metal Weighing Boxes, having a wall height,
termed “moisture, dry basis” or “moisture regain.”
when open, preferably not over 25.4 mm (1 in.).
9.2 In order to avoid confusion always use the appropriate
term.
7. Procedure
7.1 Remove the basket, shallow pan, or other container
10. Precision and Bias
supplied for use with the oven (Note 3). Weigh the container
and place in it a specimen of 10 to 50 g (0.35 to 1.75 oz) 10.1 Precision:
D1348 − 94 (2008)
10.1.1 Statistical analysis of intralaboratory (repeatability) 14.3 At the end of the specified period, quickly place the
test results on samples containing 5 to 15% moisture indicates basket and specimen in the weighing bottle again and stopper
a precision of 60.14% at the 95% confidence level. it (or stopper directly). Remove the weighing bottle from the
10.1.2 Statistical analysis of interlaboratory (reproducibil- oven and place it in a desiccator containing an efficient
ity) test results on samples containing 5 to 15% moisture desiccant, such as anhydrous calcium sulfate. Allow it to cool
indicates a precision of 60.2% at the 95% confidence level. for 1 h, momentarily open the weighing bottle to equalize the
pressure, and weigh to the nearest 0.001 g.
10.2 Bias—Nojustifiablestatementcanbemadeonthebias
of the procedure for measuring moisture in cellulose because 14.4 Return the specimen to the oven, exposing it as
no suitable reference material exists. directed above, and dry for at least 1 h more. Place it in a
desiccator to cool and weigh in accordance with 14.3. Repeat
TEST METHOD B—SPECIMEN WEIGHED OUTSIDE
the drying and weighing until the mass loss between two
OF OVEN
successive weighings is not more than 0.005 g (or until the
specimen shows a gain in mass). Designate the lowest ob-
11. Scope
served mass as D.
11.1 The scope and application of this test method are the
14.5 When constant mass has been obtained, discard the
same as those of Test Method A (see Section 4).
specimen and weigh the weighing bottle (plus basket) or can.
Designate this mass as T.
12. Summary of Test Method
14.6 Donotplaceadditionalspecimensintheovenuntilthe
12.1 See Test Method A (Section 5).
first specimens have attained constant mass.
13. Apparatus
15. Calculation
13.1 Oven Without Built-In Weighing Equipment—Anyven-
15.1 Calculatemoisture,asmeasuredoutsideoftheoven,as
tilated oven capable of maintaining a constant temperature of
follows:
105 6 3°C, with an average temperature of 105°C; continuous
Moisturecontent, % @~M 2 D!/~M 2 T!# 3100 (5)
operation below 105°C is not satisfactory.
Moisture, drybasis, regain,% 5 M 2 D / D 2 T 3100 (6)
~ ! @~ ! ~ !#
NOTE 5—In ovens having heating elements at the bottom only, and no
cross circulation, the temperature of the lower shelves should be checked
where:
before they are used.
M = original mass of the specimen (plus basket) and weigh-
13.2 Dry Air Stream—See 6.2.
ing bottle,
13.3 Shallow Glass Weighing Bottles—See 6.3. D = oven-dry mass of the specimen (plus basket), and
T = mass of the empty weighing bottle (plus basket).
13.4 Seamless Metal Weighing Boxes—See 6.4.
13.5 Weighing Bottles, glass with ground-glass stoppers, 16. Report
approximately 40 mm wide and 80 mm high.
16.1 Report the moisture in the cellulose as directed in
13.6 Wire Baskets—Fitted baskets for weighing bottles Section 9.
made from approximately 15-mesh stainless steel, Monel, or
17. Precision and Bias
othersuitablescreen.Theheightanddepthofthebasketwillbe
determined by the weighing bottle used; the basket must slide
17.1 See Section 10.
into and out of the bottle without binding. The basket should
TEST METHOD C—KARL FISCHER METHOD
have a solid bottom, but no top is required.
18. Scope
14. Procedure
18.1 This test method covers the determination of moisture
14.1 If the sample is free of lint, dust, or short fibers, place
in cellulose by titration with Karl Fischer reagent. The test
approximately 10 g (0.35 oz) of the sample into a previously
method is applicable to all types and forms of cellulose. It is
dried and desiccated wire basket (Note 2) contained in a dry
especiallyusefulwithsamplescontainingnonaqueousmaterial
weighing bottle. Stopper the weighing bottle, and weigh to the
volatile at 110°C, since such substances interfere in the
nearest 0.001 g. Designate this mass as M. Remove the basket
oven-drying methods.Anhydrides, alkalies, and large amounts
containingthespecimenfromtheweighingbottleandplacethe
of aldehydes and ketones interfere.
basket, weighing bottle, and stopper in the oven. If the
specimen includes powder-like material, transfer the specimen 18.2 The Karl Fischer titration method is especially valu-
directly into a small weighing bottle or can. Stopper the bottle able where only small amounts of samples are available. The
andweightothenearest0.001g(M).Removethestopperfrom procedure lends itself to multiple determinations.
the bottle and place the bottle containing the specimen and the
18.3 It is essential that the Karl Fischer reagent, standard
stopper in the oven.
water solution, and anhydrous methanol be protected from
14.2 Dry for2hat105 6 3°C, passing a current of dry air atmospheric moisture at all times. During the titration a st
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