ASTM D464-15(R2020) pdf free download

ASTM D464-15(R2020) pdf free download.Standard Test Methods for Saponification Number of Pine Chemical Products Including Tall Oil and Other Related Products
1. Scope
1.1 These test methods cover the determination of the saponification number of tall oil and products obtained by the fractionation of tall oil such as rosin, fatty acids and distilled tall oil as defined in Terminology D804. These test methods are also applicable to gum and wood rosin. Two test methods are covered as follows: 1.1.1 Test method using a potentiometric method, and 1.1.2 Test method using an internal indicator method. 1.2 The potentiometric method is suitable for use with both light- and dark-colored test samples. It should be considered the referee method. The internal indicator method is suitable for use only with light- and medium-colored test samples. It should be considered the alternate method. 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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 appro- priate safety, health, and environmental practices and deter- mine the applicability ofregulatory limitations prior to use. 1.5 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
3. Significance and Use
3.1 These test methods are designed to broaden the scope of the earlier editions ofthe test method by the inclusion oftall oil and tall oil derived products as test materials and is referenced in Test Methods D803. 3.2 The saponification number is an important property of tall oil and the products obtained by the fractionation oftall oil. It is the test method widely used to determine the total acid content, both free and combined, of these products. 3.3 The potentiometric test method should be used when the most reproducible results are required.
4. Preparation of Sample
4.1 If the sample for analysis is rosin, it shall consist of small pieces of rosin chipped from a freshly exposed part of a lump or lumps, and thereafter crushed to facilitate weighing and dissolution. Prepare the sample the same day on which the test is begun in order to avoid changes in properties due to surface oxidation. Changes are very pronounced on ground rosin that has a large surface area exposed to air. Existing rosin dust and powdered rosin must not be used. 4.2 If the sample is a nonhomogeneous liquid, heat the entire sample in a closed container fitted with a capillary vent or the equivalent. Some kind of agitation, even if done occasionally by hand, saves much time. Heat by immersion in open steam or hot water bath to avoid overheating. When dealing with crystallized rosin, a higher temperature of ap- proximately 160°C may be needed. Remove samples for testing only when the entire sample is homogeneous and has been well stirred.
8. Procedure
8.1 Transfer 2.95 to 3.05 g of the sample, weighed to the nearest 0.001 g, to the Erlenmeyer flask. Ifnecessary, 10 mL of isopropyl alcohol-toluene solution (1:1) can be added to the flask to pre-dissolve the sample. Using a constant delivery pipet or volumetric pipet add 50.0 mL of the alkali solution. Add several PTFE boiling stones or glass beads and connect the flask to the condenser. 8.2 Place the flask on a hot plate and maintain the solution at reflux for 1 h. At the end ofthe reflux time, while the sample is still warm, transfer the contents of the Erlenmeyer flask into a 400-mL tall-form beaker rinsing with 100 mL of isopropyl alcohol in three washings. Place samples on a heated surface until they can be titrated. In order to avoid highly variable results, make sure that the temperature of the samples is approximately 60 to 70°C when titrated.