ASTM E775-15(R2021) pdf free download

ASTM E775-15(R2021) pdf free download.Standard Test Methods for Total Sulfur in the Analysis Sample of Refuse-Derived Fuel
9. Reagents
9.1 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 ofthe American Chemical Society, where such specifications are available. 4 Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high purity to permit its use without impacting the accuracy of the determination. 9.2 Purity ofWater—Unless otherwise indicated, references to water shall be understood to mean reagent water, Type III, conforming to Specification D1193. 9.3 Barium Chloride Solution (100 g/L)—Dissolve 100 g of barium chloride (BaCl 2 ·2H 2 O) and dilute to 1 L with water. 9.4 Bromine Water (saturated)—Add an excess of bromine to 1 L of water. 9.5 Eschka Mixture—Thoroughly mix two parts by weight of light calcined magnesium oxide (MgO) with one part of anhydrous sodium carbonate (Na 2 CO 3 ). Both materials should be as free as possible from sulfur. 9.6 Hydrochloric Acid (1 + 1)—Mix equal volumes of con- centrated HCl (sp gr 1.19) and water. 9.7 Hydrochloric Acid (1 + 9)—Mix one volume of concen- trated HCl (sp gr 1.19) with nine volumes of water. 9.8 Methyl Orange Indicator Solution (0.2 g/L)—Dissolve 0.2 g of methyl orange in 1000 mL of hot water and filter.9.9 Sodium Carbonate (saturated solution)—Dissolve ap- proximately 60 g of crystallized sodium carbonate (Na 2 CO 3 ·10H 2 O) or 20 g of anhydrous sodium carbonate (Na 2 CO 3 ) in 100 mL of water, using a sufficient excess of Na 2 CO 3 to ensure a saturated solution. 9.10 Sodium Hydroxide Solution (100 g/L)—Dissolve 100 g of sodium hydroxide (NaOH) in 1 L of water. This solution may be used in place of Na 2 CO 3 solution.
10. Procedure
10.1 Preparation ofSample and Eschka Mixture—Weigh to the nearest 0.1 mg about 1 g ofmixed air-dried analysis sample and 3 g of Eschka mixture on glazed paper. Mix thoroughly. The amount of sample to be taken will depend on the amount of BaCl 2 solution required (see 10.3.5 and Note 2). 10.1.1 Quantitatively transfer the mixture to a porcelain capsule or porcelain crucible or platinum crucible, and cover with about 1 g of Eschka mixture. 10.2 Ignition—Heat the crucible over a gas flame as de- scribed in 10.2.1, or in a gas or electrically heated muffle furnace as described in 10.2.2. The use of artificial gas for heating the sample and Eschka mixture is permissible only when the crucibles are heated in a muffle furnace (see Note 3). 10.2.1 Heat the crucible, placed in a slanting position partially covered on a triangle, over a very low flame. This prevents rapid expulsion ofthe volatile matter and affords more complete oxidation of the sulfur. After 30 min of low-flame heating, gradually increase the temperature and occasionally stir the mixture until all black particles have disappeared, which is an indication of complete combustion.10.2.2 Place the crucible in a cold muffle furnace and gradually raise the temperature to 800 6 25 °C in about 1 h. Maintain this maximum temperature until upon stirring all black particles have disappeared (about 1 1 ⁄ 2 h). 10.3 Subsequent Treatment: 10.3.1 Remove the crucible, cool, and empty the contents quantitatively into a 200-mL beaker. Digest with 100 mL ofhot water for 1 ⁄ 2 to 3 ⁄ 4 h with occasional stirring. 10.3.2 Decant the supernatant liquid through a filter into a 600-mL beaker. Wash the insoluble matter with hot water several times using 25 mL of water at each washing and filter the washings through filter paper into a 600-mL beaker. After washing, transfer the insoluble matter to the filter and wash five times with hot water, keeping the mixture well agitated, collecting the washings in the 600-mL beaker. 10.3.3 Treat the filtrate with 10 to 20 mL of saturated bromine water. Make slightly acid with HCl and boil to expel the liberated bromine.