ASTM D3651-16(2021)e1

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.
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Designation: D3651 − 16 (Reapproved 2021)
Standard Test Method for
Barium in Brackish Water, Seawater, and Brines
This standard is issued under the fixed designation D3651; 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.
ε NOTE—The WTO caveat was editorially added in November 2021.
1. Scope D3370 Practices for Sampling Water from Flowing Process
Streams
1.1 This test method covers the determination of soluble
D4691 Practice for Measuring Elements in Water by Flame
barium ion in brackish water, sea-water, and brines by atomic
Atomic Absorption Spectrophotometry
absorption spectrophotometry.
D4841 Practice for Estimation of Holding Time for Water
1.2 The actual working range of this test method is 1 to 5
Samples Containing Organic and Inorganic Constituents
mg/L barium.
D5810 Guide for Spiking into Aqueous Samples
D5847 Practice for Writing Quality Control Specifications
1.3 This test method was used successfully on artificial
brine samples. It is the user’s responsibility to ensure the for Standard Test Methods for Water Analysis
validity of this test method for waters of untested matrices.
3. Terminology
1.4 The values stated in SI units are to be regarded as
3.1 Definitions:
standard. The values given in parentheses are mathematical
3.1.1 For definitions of terms used in this standard, refer to
conversion to inch-pound units that are provided for informa-
Terminology D1129.
tion only and are not considered standard.
4. Summary of Test Method
1.5 This standard does not purport to address all of the
3,4
safety concerns, if any, associated with its use. It is the
4.1 This test method is dependent upon the fact that
responsibility of the user of this standard to establish appro-
metallic atoms, in the ground state, will absorb light of the
priate safety, health, and environmental practices and deter-
samewavelengththeyemitwhenexcited.Whenradiationfrom
mine the applicability of regulatory limitations prior to use.
a given excited element is passed through a flame containing
1.6 This international standard was developed in accor-
ground state atoms of that element, the intensity of the
dance with internationally recognized principles on standard-
transmitted radiation will decrease in proportion to the amount
ization established in the Decision on Principles for the
of the ground state element in the flame. A hollow-cathode
Development of International Standards, Guides and Recom-
lamp whose cathode is made of the element to be determined
mendations issued by the World Trade Organization Technical
provides the radiation.
Barriers to Trade (TBT) Committee.
5,6
4.2 The metal atoms to be measured are placed in the
beam of radiation by aspirating the specimen into an oxidant-
2. Referenced Documents
fuel flame. A monochromator isolates the characteristic radia-
2.1 ASTM Standards:
tion from the hollow-cathode lamp and a photosensitive device
D1129 Terminology Relating to Water
measures the attenuated transmitted radiation.
D1193 Specification for Reagent Water
4.3 Sincethevariableandsometimeshighconcentrationsof
D2777 Practice for Determination of Precision and Bias of
matrix materials in the waters and brines affect absorption
Applicable Test Methods of Committee D19 on Water
Fletcher, G. F., and Collins, A. G., Atomic Absorption Methods of Analysis of
This test method is under the jurisdiction of ASTM Committee D19 on Water Oil Field Brines: Barium, Calcium, Copper, Iron, Lead, Lithium, Magnesium,
and is the direct responsibility of Subcommittee D19.05 on Inorganic Constituents Manganese, Potassium, Sodium, Strontium, and Zinc, U.S. Bureau of Mines, Report
in Water. of Investigations 7861, 1974, 14 pp.
Current edition approved Nov. 1, 2021. Published December 2021. Originally Collins, A. G., Geochemistry of Oil Field Waters, Elsevier Publishing Co.,
approved in 1978. Last previous edition approved in 2016 as D3651 – 16. DOI: Amsterdam, The Netherlands, 1974.
10.1520/D3651-16R21E01. Angino, E. E., and Billings, G. K., Atomic Absorption Spectrophotometry in
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Geology, Elsevier Publishing Co., New York, NY, 1967.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Dean, J. A., and Rains, T. C., Editors, Flame Emission and Atomic Absorption
Standards volume information, refer to the standard’s Document Summary page on Spectrophotometry, Volume 1, Theory, 1969, Volume 2, Components, 1971, and
the ASTM website. Volume 3, Elements and Matrices, 1975, Marcel Dekker, New York, NY.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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D3651 − 16 (2021)
differently, it becomes imperative to prepare standard samples sufficiently high purity to permit its use without lessening the
with matrices similar to the unknown samples. This is accom- accuracy of the determination.
plished by preparing synthetic standard samples with similar
8.2 Unless otherwise indicated, reference to water shall be
compositions as the unknowns. The standard samples and
understood to mean reagent water conforming to Specification
unknown samples are aspirated, the absorption readings
D1193, Type I. Other reagent water types may be used
recorded, a calibration curve for the standard samples
provided it is first ascertained that the water is of sufficiently
constructed, and the original sample concentration calculated.
high purity to permit its use without adversely affecting the
precision and bias of the test method. Type III water was
5. Significance and Use
specified at the time of round-robin testing of this test method.
5.1 Since water containing acid-soluble barium compounds
8.3 Barium Solution, Stock (1 mL = 1 mg Ba)—Dissolve
is known to be toxic, this test method serves the useful purpose
1.779 g of barium chloride (BaCl ·2H O) in 50 mL of
2 2
of determining the barium in brackish water, seawater, and
concentrated hydrochloric acid (HCl) (sp gr 1.19) and about
brines.
700 mL of water. Dilute the solution to 1 L with water. One
millilitre of this solution contains 1 mg of barium.Apurchased
6. Interferences
stock solution of appropriate known purity is also acceptable.
6.1 Ionization interference is controlled by adding potas-
8.4 Barium Solution, Standard (1 mL = 0.1 mg Ba)—Add
sium.
100mLofbariumsolutionstockto50mLofconcentratedHCl
6.2 Matrix interferences, caused by high concentrations of
(sp gr, 1.19) and about 600 mL of water. Dilute the solution to
varied ions, and spectral interference, caused by high calcium
1 L with water. One millilitre of this solution contains 0.1 mg
concentrations, are controlled by matching the matrices.
of barium.
6.3 This test method is subject to calcium interference, but
8.5 Potassium Solution(1mL=10mgK)—Dissolve 19.07
the procedure provided eliminates the interference effect of up
gofpotassiumchloride(KCl)inabout700mLofwater.Dilute
to 750 mg/L calcium. Calcium interference can also be
the solution to 1 L with water. One millilitre of this solution
minimized by using a secondary wavelength of 455.4 nm.
contains 10 mg of potassium. A purchased stock solution of
appropriate known purity is also acceptable.
6.4 In high sulfate waters, such as seawater, barium will be
precipitatedasbariumsulfateandwillnotbepresentassoluble
8.6 Calcium Solution(1mL = 10mgCa)—Dissolve54.66g
barium and will, therefore, be below the detection limit of the
of calcium chloride hexahydrate (CaCl ·6H O) in 500 mL of
2 2
test method.
water. Dilute the solution to 1 L with water. One millilitre of
this solution contains 10 mg of calcium. A purchased stock
7. Apparatus
solution of appropriate known purity is also acceptable.
7.1 Atomic Absorption Spectrophotometer—for use at 553.6
8.7 Sodium Solution (1 mL = 10 mg Na)—Dissolve 25.14 g
nm. A general guide for the use of flame atomic absorption
sodiumchloride(NaCl)in500mLofwater.Dilutethesolution
applications is given in Practice D4691.
to1Lwithwater.Onemillilitreofthissolutioncontains10mg
of sodium. A purchased stock solution of appropriate known
NOTE 1—The manufacturer’s instructions should be followed for all
instrumental parameters. Wavelengths other than 553.6 nm may be used
purity is also acceptable.
only if they have been determined to be equally suitable.
8.8 Hydrochloric Acid (sp gr 1.19)—Concentrated hydro-
7.1.1 Multielement Hollow-Cathode Lamps are available
chloric acid, ultrapure or equivalent.
and have been found satisfactory.
8.9 Oxidant:
7.2 Pressure-Reducing Valves—The supplies of fuel and
8.9.1 Nitrous Oxide is the oxidant required for this test
oxidant shall be maintained at pressures somewhat higher than
method.
the controlled operating pressure of the instrument by suitable
8.10 Fuel:
valves.
8.10.1 Acetylene—Standard, commercially available acety-
lene is the usual fuel. Acetone, always present in acetylene
8. Reagents and Materials
cylinders, can be prevented from entering and damaging the
8.1 Purity of Reagents—Reagent grade chemicals shall be
burner head by replacing a cylinder which has only 690 kPa
used in all tests. Unless otherwise indicated, it is intended that
(100 psig) of acetylene remaining.
all reagents shall conform to the specifications of the Commit-
8.11 Filter Paper—Purchase suitable filter paper. Typically
teeonAnalyticalReagentsoftheAmericanChemicalSociety,
the filter papers have a pore size of 0.45-µm membrane.
where such specifications are available. Other grades may be
Material such as fine-textured, acid-washed, ashless paper, or
used, provided it is first ascertained that the reagent is of
glass fiber paper are acceptable. The user must first ascertain
that the filter paper is of sufficient purity to use without
ACS Reagent Chemicals, Specifications and Procedures for Reagents and
adversely affecting the bias and precision of the test method.
Standard-Grade Reference Materials, American Chemical Society, Washington,
DC. For suggestions on the testing of reagents not listed by theAmerican Chemical
9. Sampling
Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset,
9.1 Collect the sample in accordance with Practices D3370
U.K., and the United States Pharmacopeia and National Formulary, U.S. Pharma-
copeial Convention, Inc. (USPC), Rockville, MD. and D4841.
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D3651 − 16 (2021)
TABLE 1 Determination of Precision and Bias
9.2 Add 2.0 mL of HCl per litre of water to prevent
precipitation of soluble barium. Statistically
Amount Amount
Bias, Significant
Added, Found, S S
T O
±% (95 % confi-
mg/L mg/L
10. Calibration and Standardization
dence level)
53.0 53.3 4.9 4.11 + 0.43 no
10.1 Prepare standards of 0.0, 1.0, 2.5, 5.0, and 10 mg/L of
98.0 94.9 9.3 9.21 −3.19 no
Ba by adding 0, 1.0, 2.5, 5.0, and 10 mL of barium standard
603 541 47.8 46.25 −10.4 yes
solution to 100-mL volumetric flasks. 1009 901 90.7 102.3 −10.7 yes
10.2 Add to each standard 5 mLof concentrated HCl (sp gr
1.19), 10 mL of potassium solution (1 mL = 10 mg of K), 7.5
mL of calcium solution (1 mL = 10 mg of Ca), and 15 mL of
sodium solution (1 mL = 10 mg of Na). Dilute these solutions
11.1.2.1 Transferanaliquotofthewaterorbrine,containing
to 100 mL with water.
approximately0.1to0.5mgofbarium,toa100-mLvolumetric
10.3 The method of operation varies with different models flask.
11.1.2.2 Add 5.0 mL of concentrated HCl (sp gr 1.19) and
of atomic absorption spectrophotometers. Therefore, no at-
tempt is made here to describe in detail the steps for placing an 10 mL of potassium solution (1 mL = 10 mg K) to the flask.
Dilute the sample to 100 mL with water.
instrument into operation. However, the parameters that follow
have been found suitable for some types of equipment.
11.2 Operate the instrument in the concentration mode.
10.3.1 Turn on the instrument.
11.3 Aspiratethesampleandrecordtheabsorbancereading.
10.3.2 Apply the current to the cathode lamp as suggested
bythemanufacturer:Allowtheinstrumenttowarmupuntilthe
12. Calculation
energy source stabilizes. The time required is from 10 to 20
min. 12.1 Calculate the concentration of barium ion in the
10.3.3 Ignite an air-acetylene flame. Increase the fuel flow original sample in milligrams per litre using the calibration
until the flame is luminescent. Let the flame stabilize (about curve prepared in 10.4.2 through 10.4.4 as follows:
10–15 s). Switch to the nitrous oxide. Provide concentration of
Barium concentration, mg/L 5 A 3D/V
metal in accordance with the instructions outlined by the
where:
manufacturer, to give maximum sensitivity.
A = barium read from the calibration curve,
10.3.4 Let the fuel-oxidant mixture burn for 10 to 15 min
D = dilution volume (volume the sample was diluted to),
before operating the instrument.
and
10.4 Operate the instrument in the absorption mode and
V = volume of sample.
aspirate the 0 mg/L barium standard and set the instrument to
zero absorbance.
13. Precision and Bias
10.4.1 Aspirate the 10 mg/Lbarium standard and record the
13.1 The precision and bias data presented in Table 1 for
absorbance reading. This value is used for roughly estimating
this test method meet the requirements of Practice D2777. The
the barium concentration in a sample.
data shown have been rounded from unrounded data in the
10.4.2 Operate the instrument in the concentration mode
research report.
and optimize the instrument settings.
10.4.3 Aspirate the 1.0, 2.5, and 5.0 mg/Lbarium standards 13.2 The precision and bias estimates in Table 1 are based
and record the absorbance readings.
on an interlaboratory study on four artificial brine samples
10.4.4 Construct a calibration curve from the barium con- containing various amounts of barium and interfering ions as
centrations and absorbance readings by plotting the milligrams
shown in Table 2. One analyst in one laboratory and two
per litre of barium versus the absorbance readings. analysts in each of four laboratories performed single determi-
nations on each of three days. Practice D2777 was used in
11. Procedure developing these precision and bias estimates. It is the user’s
responsibility to ensure the validity of this test method for
11.1 Determine barium at the 553.6-nm wavelength with a
waters of untested matrices.
nitrous oxide-acetylene flame.
11.1.1 Operate instrument in an absorption mode. 13.3 Precision and bias for this test method co
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