1、(Issued 1 Sep. 1992) C 213CRD-C 213-92Test Method for the Presence of Sugar in Cement, Mortar, Concrete,or Aggregates1. Scope1.1 This test method* is used to detect the pres-ence of sugar; it is a qualitative not a quantitative test.2. Significance and Use2.1 This test is intended to be used as a sc
2、reeningmethod to detect sugar. It is very delicate, easily detect-ing 0.001 percent of sugar, and is not interfered with bythe ordinary mineral salts. The presence of lime some-times gives the solution a green tint, but this cannot bemistaken for the sugar test. The test will detect both su-crose an
3、d invert sugar in small quantities, while theFehling test will detect only invert sugar.3. Special Solutions Required3.1 Alpha-naphthol. Dissolve 10 g of alpha-naph-thol in 100 mL of absolute alcohol. The alpha-naphtholsolution becomes less sensitive on standing, and shouldbe made up in small quanti
4、ty each time a test is made.3.2 Sulfuric Acid. Concentrated sulfuric acid, freefrom nitric acid, is required.4. Procedure4.1 Place about 20 to 30 g of the pulverized sam-ple in a small beaker, add a little more than enoughwarm water to cover the sample, and allow to stand,with occasional stirring, f
5、or 5 min. Filter through a110-mm paper into a test tube. Wash the filter paperused in the determination very thoroughly with hotwater before the solution of the sample is pouredthrough. This is necessary because some papers are im-pregnated with starch-like organic matter, which maygive a faint test
6、 for sugar.4.2 Cool to room temperature and add 3 to 4 dropsof alpha-naphthol solution. Mix by shaking. Holdingthe tube in an inclined position, slowly pour in concen-trated sulfuric acid, until the acid forms a layer in thebottom of the tube about 10-mm thick. If sugar is pres-ent, a bright purple to violet ring will form at the planeof separation of the two solutions.* This test was provided by Mr. T. A. Hicks of the Universal Atlas Cement Co.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
