Asphalt acid number

The composition of montan wax depends on the material from which it is extracted, but all contain varying amounts of wax, resin, and asphalt. Black montan wax may be further processed to remove the resins and asphalt, and is known as refined montan wax. White montan wax has been reacted with alcohols to form esters. The wax component of montan is a mixture of long-chain (C24—C q) esters (62—68 wt %), long-chain acids (22—26 wt %), and long-chain alcohols, ketones, and hydrocarbons (7—15 wt %). Cmde montan wax from Germany typically has a melting point of 80°C, an acid number of 32, and a saponification number of 92. 

Substituted Amide Waxes. The product of fatty acid amidation has unique waxlike properties (13). Probably the most widely produced material is N,1S7-distearylethylenediarnine [110-30-5] which has a melting point of ca 140°C, an acid number of ca 7, and a low melt viscosity. Because of its unusuaHy high melting point and unique functionaHty, it is used in additive quantities to raise the apparent melting point of themoplastic resins and asphalts, as an internal—external lubricant in the compounding of a variety of thermoplastic resins, and as a processing aid for elastomers. 

The acid number is a measure of the acidity of a product and is used as a guide in the quality control of resid or asphalt properties. Since a variety of oxidation products contribute to the acid number, and the organic acids vary widely in service properties, so the test is not sufficiently accurate to predict the precise behavior of asphalt in service. 

The total acid numbers (TAN) and the experimentally determined optimal NaOH concentrations for Kern River, Wilmington, and other viscous, asphaltic crude oils are given in Table III. 

The acid number is a measure of the acidity of a product and is used as a guide in the quality control of asphalt properties. Because a variety of... 

The saponification number expresses the amount of base that will react with 1 g of a sample when heated in a specific manner. Since certain elements are sometimes added to asphalt and also consume alkali and acids, the results obtained indicate the effect of these extraneous materials in addition to the saponifiable material present. In the test method (ASTM D94 IP 136), a known weight of the sample is dissolved in methyl ethyl ketone or a mixture of suitable solvents, and the mixture is heated with a known amount of standard alcoholic potassium hydroxide for between 30 and 90 minutes at 80°C (176°F). The excess alkali is titrated with standard hydrochloric acid and the saponification number is calculated. 

The liner plate lining of the underside of a concrete cover does not offer permanent protection. For one thing, there is no membrane between the liner plates and the concrete-only the layer of hot asphalt over the mortar joints. The liner plates are not as dense as, have a higher absorption than, acid brick-6% allowable-and they are thinner than acid brick, The absorption testing of liner plates is accomplished under ASTM C-301-by no means as stringent a test as that used for acid brick. Consequently, the economical life of this kind of a cover is limited. In vessels handling ambient temperature wastes, the cover may last a number of years. But if the vessel operates at an elevated temperature and contains a volatile corrosive such as hydrochloric acid, tile may start falling off in less than a year. In the past the only alternative was the same kind of covers used for steel tanks. 

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