BS ISO 6587-2021 pdf free download – Paper, board and pulps — Determination of conductivity of aqueous extracts.
This document specifies a method for the determination of the conductivity of aqueous extracts ofpaper, board or pulp, these extracts having been prepared by a hot or cold method.
The method is applicable to all kinds of paper, board and pulps, except for papers used for electricalpurposes.For high purity papers used for electrical purposes, see method given in EN 60554-2.
2Normative references
The following documents are referred to in the text in such a way that some or all of their contentconstitutes requirements of this document. For dated references, only the edition cited applies. Forundated references, the latest edition of the referenced document (including any amendments) applies.ISo 186,Paper and board — Sampling to determine average quality
ISO 287, Paper and board — Determination of moisture content of a lot —Oven-drying method
IS0 638-1,Paper; board, pulps and cellulosic nanomaterials — Determination of dry matter content byoven-drying method —Part i: Materials in solid form
ISo 7213,Pulps —Sampling for testing
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:- ISO online browsing platform: available at https://www.iso.org/obp
—IEC Electropedia: available at https://www.electropedia.org/3.1
conductivity
measure of the effect of the presence of dissolved substances in a solution to conduct electricity
Note 1 to entry:Conductivity does not measure the same solution properties as either osmolality or osmolarityand does not produce equivalent results.Conductivity only measures those substances that produce ions anddoes not measure dissolved substances that do not produce ions.
[SOURCE: IS0 18369-1:2017,3.1.6.7]
4 Principle
A2g sample is extracted for 1 h with 100 ml of boiling or cold,distilled or deionized water.Measurementof the conductivity of the extract at 25 C by means of a conductivity meter or resistance bridge, usingalternating current.
5Reagents
5.1 Distilled or deionized water
Distilled or deionized water shall be used throughout the test. The conductivity of the water shall notexceed 0,2 mS/m after boiling and cooling as specified in 8.2.2.
NOTE Usually, both distillation and deionization are required.Unless great care is exercised when distilling,and with the materials employed in the condenser and subsequent surfaces with which the condensed vapourwould possibly come in contact, the distillate can fail to reach the required level of conductivity.
When it is not possible to obtain water of the specified purity, water with a higher conductivity may beused, but the conductivity of the water used should be stated in the test report.
5.2 Potassium chloride, standard solutions
Use potassium chloride(KCl) of recognized analytical reagent grade, powdered, or fine crystals. Dry for2 h at 105 C±2 C and immediately prepare the following two solutions.
5.2.10,01 mol/l solution
Dissolve 0,745 g of the potassium chloride in water having a conductivity not greater than 0,2 mS/m,and dilute to 1 000 ml.
5.2.2 0,001 mol/lsolution
Dilute 100 ml of the 0,01 mol/l solution (5.2.1) to 1 000 ml.
Store the solutions in waxed glass bottles with ground glass stoppers. The conductivity values, inmillisiemens per meter, of the two solutions,are given in Table 1.
6 Apparatus
The usual laboratory apparatus and, in particular, the following shall be used.
6.1 Flasks of chemically resistant glass,with ground glass joints,stoppers and efficient water-cooled reflux condensers made of the same quality of glass.All glassware shall be carefully rinsed withboiling distilled or deionized water (5.1).
6.2Electric heater, adjustable at least to 200 w.
6.3 Conductivity meter or resistance bridge,with measuring cells provided with black platinumelectrodes of area approximately 1 cm2, and capable of indicating the conductance of an aqueous extractwith an error of less than ±5 % in the frequency range of 50 Hzto 3 000 Hz.
6.4Constant-temperature bath, capable of maintaining a temperature of 25 °C±0,5 °C.BS ISO 6587 pdf download.