ASTM D2710-09(2018)

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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: D2710 − 09 (Reapproved 2013) D2710 − 09 (Reapproved 2018)
Designation: 299/92 (98)
Standard Test Method for
Bromine Index of Petroleum Hydrocarbons by Electrometric
Titration
This standard is issued under the fixed designation D2710; 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
1.1 This test method covers the determination of the amount of bromine-reactive material in petroleum hydrocarbons and is thus
a measure of trace amounts of unsaturates in these materials. It is applicable to materials having bromine indexes below 1000.
1.2 This test method is applicable only to essentially olefin-free hydrocarbons or mixtures that are substantially free from
material lighter than isobutane and have a distillation end point under 288°C (550°F).288 °C (550 °F).
NOTE 1—This procedure has been cooperatively tested on materials with bromine indexes in the range from 100 to 1000. These materials include
petroleum distillates such as straight-run and hydrocracked naphtha, reformer feed, kerosine, and aviation turbine fuel.
NOTE 2—Materials with bromine index greater than 1000 should be tested for bromine number using Test Method D1159/IP 130.
NOTE 3—Bromine index of industrial aromatic hydrocarbons should be determined using Test Method D1492 or D5776. The subcommittee is currently
examining ways to achieve more consistent end point values.
1.3 The values stated in SI units are to be regarded as standard. The values stated in inch-pound given in parentheses after SI
units are provided for information only.only and are not considered 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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.5 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.
This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricantsand is the direct responsibility of Subcommittee
D02.06 on Analysis of Liquid Fuels and Lubricants.
Current edition approved Oct. 1, 2013Dec. 1, 2018. Published October 2013December 2018. Originally approved in 1968. Last previous edition approved in 20092013
as D2710 – 09.D2710 – 09 (2013). DOI: 10.1520/D2710-09R13.10.1520/D2710-09R18.
In the IP, this test method is under the jurisdiction of the Standardization Committee.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D2710 − 09 (2018)
2. Referenced Documents
2.1 ASTM Standards:
D1159 Test Method for Bromine Numbers of Petroleum Distillates and Commercial Aliphatic Olefins by Electrometric Titration
D1492 Test Method for Bromine Index of Aromatic Hydrocarbons by Coulometric Titration
D5776 Test Method for Bromine Index of Aromatic Hydrocarbons by Electrometric Titration
3. Terminology
3.1 Definitions:
3.1.1 bromine index, n—the number of milligrams of bromine that will react with 100 g 100 g of sample under the conditions
of the test.
4. Summary of Test Method
4.1 A known mass of the sample dissolved in a specified solvent is titrated with standard bromide-bromate solution. The end
point is indicated by a dead stop electrometric titration apparatus when the presence of free bromine causes a sudden change in
the electrical conductivity of the system.
5. Significance and Use
5.1 This test method provides a measure of trace amounts of unsaturated hydrocarbons in petroleum distillates boiling up to
288°C (550°F).288 °C (550 °F). An estimate of the quantity of these materials is useful in assessing the suitability of the lighter
fractions for use as reaction solvents.
6. Apparatus
6.1 Electrometric End Point Titration Apparatus—Any apparatus designed to perform titrations to pre-set end points (see Note
4) may be used in conjunction with a high-resistance polarizing current supply capable of maintaining approximately 0.8 V 0.8 V
across two platinum electrodes and with a sensitivity such that a voltage change of approximately 50 mV 50 mV at these electrodes
is sufficient to indicate the end point. Other types of commercially available electric titrimeters, including certain pH meters, have
also been found to be suitable.
NOTE 4—Pre-set end point indicated with polarized electrodes provides a detection technique similar to the dead stop technique specified in previous
versions of this test method.
6.2 Titration Vessel—A jacketed glass vessel of approximately 150-mL150 mL capacity of such a form that can be conveniently
maintained at 00 °C to 5°C (325 °C (32 °F to 41°F).41 °F). A pair of platinum electrodes spaced not more than 5 mm 5 mm apart
shall be mounted to extend well below the liquid level. Stirring shall be by a mechanical or electromagnetic stirrer and shall be
rapid, but not so vigorous as to draw air bubbles down to the electrodes.
6.3 Burets, 1010 mL and 50-mL50 mL capacity.
6.4 Iodine Number Flasks, glass-stoppered, 500-mL500 mL capacity.
7. Reagents
7.1 Purity of Reagents—Reagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that all
reagents shall conform to the specifications of the American Chemical Society where such specifications are available. Other
grades may be used, providing it is first ascertained that the reagent is of sufficiently high purity to permit its use without lessening
the accuracy of the determination.
7.2 Purity of Water—Unless otherwise indicated, references to water shall be understood to mean distilled water, or water of
equivalent purity.
7.3 Preparation and Standardization : Standardization:
7.3.1 Bromide-Bromate Standard Solution (0.05 N0.05 N)—Dissolve 5.1 g 5.1 g of potassium bromide (KBr) and 1.4 g 1.4 g
potassium bromate (KBrO ) in water and dilute to 1 L. 1 L. Standardize to four significant figures as follows: Place 50 mL 50 mL
of glacial acetic acid (Warning—WarningPoison. —Poison. Combustible. May be fatal if swallowed. Causes severe burns.
Harmful if inhaled) and 1 mL 1 mL of concentrated hydrochloric acid (HCl, sp gr 1.19) (Warning—WarningPoison.—Poison.
Corrosive. May be fatal if swallowed. Liquid and vapor cause severe burns. Harmful if inhaled.) in a 500-mL500 mL iodine
number flask. Chill the solution in an ice bath for approximately 10 min, 10 min, and with constant swirling of the flask, add from
a 50-mL50 mL buret 4040 mL to 45 mL 45 mL of bromide-bromate solution, estimated to the nearest 0.01 mL, 0.01 mL, at a rate
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 Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For Suggestions on the testing of reagents not listed by
the American Chemical Society, see Annual Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and National
Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville, MD.
D2710 − 09 (2018)
such that the addition takes between 9090 s and 120 s. 120 s. Stopper the flask immediately, shake the contents, place it again in
the ice bath, and add 5 mL 5 mL of potassium iodide (KI) solution in the lip of the flask. After 5 min, 5 min, remove the flask from
the ice bath and allow the KI solution to flow into the flask by slowly removing the stopper. Shake vigorously, add 100 mL 100 mL
of water in such a manner as to rinse the stopper, lip, and walls of the flask, and titrate promptly with the standard sodium
thiosulfate (Na S O ) solution. Near the end of the titration, add 1 mL 1 mL of starch indicator solution and titrate slowly to the
2 2 3
disappearance of the blue color. Calculate the normality of the bromide-bromate solution as follows:
N 5 A N /A (1)
1 2 2 1
where:
where:
N = normality of the bromide-bromate solution,
A = millilitres of the bromide-bromate solution,
N = normality of the Na S O solution, and
2 2 2 3
A = millilitres of the Na S O solution required for titration of the bromide-bromate solution.
2 2 2 3
7.3.2 Potassium Iodide Solution (150 (150 g g/L)—⁄L)—
...